# Basic 3120xp Mods



## Wet1 (Feb 2, 2009)

I decided to sit down and do some basic mods to my EPA 3120xp yesterday. I didn't want to put a lot of money in this saw, so I did what I could for as little money as possible.

Like others, I finally got fed up with the 9,600 rpm limiter in my EPA 3120. I know husky has a non-epa coil and flywheel for this saw (I believe this limits around 11.5k) that is still sold in the ROW, but I wasn't crazy about spending a couple of hundred dollars on a saw I only paid $600 for to begin with. Romeo had told me the unlimited 272 coil can be adapted by changing the center poll/laminate and swapping in the stock piece, so I thought I'd give that a try. I should warn anyone considering doing this swap, the 272 has no limiter in it so it's very possible you could damage your saw since there's no safeguard with is coil... Please understand you could throw a rod or break your crank by doing this!!! Just want to make sure everyone knows this is a possibility when removing rev limiters...

I bought a clean used 272 coil off ebay for $25 for this swap. Looking at the two coils, they appear almost identical other than the color. The spark plug wire comes out at a slightly different angle and the plug wire itself on the 272 coil was a little shorter. 











I started off by finding out what the timing was with the stock coil. I crudely found TDC and marked both the FW and a spot on the jug so I could read it with my timing light from the top. I suspect I didn't find exactly TDC, but I'm sure I was very close (+/- a degree or two). Close enough was fine with me, I just needed a reference point since my Snap On digital inductive advance timing light allows me to dial in the advance. With TDC marked, I found the stock green 3120 coil was giving me about 53° BTDC and advanced to around 24° as it reved up. Now that I had this info, I knew what timing numbers I needed out of the 272 coil. 

Since the pole/laminate in the two coils looked to be identical, I went ahead and installed the 272 coil without changing out the center laminate. The coil fit just as the factory coil did and with no issues. The plug wire location/angle did not hit the case on the saw, so I didn't have to notch the case at all (I thought I might have to given the slightly difference in the angle of the plug wire). The plug wire was a little short if I used the factory wire locations (clips in the plastic), but I just bypassed one or two of the clips and found it was still very secure and fit just fine. I could have changed the plug wire(s), but this worked so I decided not to screw around with it and chance breaking something.










Not knowing what was going to happen, I decided to see if it would start w/o making any other changes other than installing the 272 coil. To my surprise, the saw started and seemed to run well. Checking the timing I found the saw was idling at around 51°, which was very close to what I was seeing with the factory green 3120 coil. After building up the rpm's with the 272 coil installed, the timing was again sitting around 24° BTDC... right where it was with the factory coil. I suppose the timing could be advanced a little to get a little more performance out of the saw, but I didn't want to bother. If the timing was not correct after installing the 272 coil, I would have tried swapping the center sections. If it was out by a lot, I would have needed to re index the FW. I would have done this by removing the FW and the key, and then relocate it to get the proper timing. Luckily, I didn't have to do this. The best part, no premature hammering of the limiter... music to my ears!!!

Since the non- epa saws come with a larger high speed jet, and I wanted to open my muffler up a little, I had to richen my carb up a little. This saw doesn't have an adjustable high jet (I HATE NON ADJUSTABLE CARBS!!!), so I had to do some mods to the factory jet. To do this you have to access the carb and take out the high speed jet. You first have to remove the aluminum casting that sits over the carb (four allen screws). Once that plate is removed above the carb, the carb is free to be removed from the saw. You don't have to remove the carb to do this mod, but I wanted to clean the saw up a little so I elected to remove it by disconnecting the two linkages and the fuel line. You next remove the top plate on the carb (four small screws) to expose the high speed jet as shown below... 




The size of the jet is stamped right into the jet itself. My saw is fairly new and it had a 1.12mm jet in it. The non-epa saws sold in the ROW come with a larger 1.16mm jet. If I were only doing the coil change, I would have wanted this 1.16mm jet. Since I was going to open up the muffler a little as well, I decided to go a little larger. Warbo jets can be bought, but I didn't have one on hand (this was kind of something I just decided to sit down and do yesterday), so I reamed out my factory jet to about .0465", which is about 1.18mm. I don't know how close this will be to ideal, but I'm hoping this will be close enough. Once I get some time to do some cutting with it, I'll keep a very close eye on the plug for a while. I'm hoping this should be sufficiently rich to keep the saw safe since I wont be using it to mill. Did I mention I hate non-adjustable carbs???

I next wanted to open the muffler up a little. I did this by removing the muffler and drilling four 3/8" holes around the factory exhaust exit. This area is curved and kind of tough to drill into because of the shape, so I drilled pilot holes with a 1/8" bit first before going to the larger drill bit. After I was done I removed any major burs and completely blew out the muffler to remove steel chips. Four 3/8 holes isn't a lot of additional surface area, but it should allow it to breath quite a bit better. The holes are actually a little larger than this because of the angle they are drilled at, but 3/8" was the size of the bit I used. I could have made the holes larger, but I didn't want to go crazy with it. I next cut the louvers out of the cover that holds the spark arrester screen. I started the saw w/o the screen in place and let it run for a minute or two to make sure any remaining steel chips that might have been stuck in the muffler had a way to escape. I later reinstalled the screen. I forgot to take some pics of this mod, but it's difficult to tell the muffler has been modded by looking at it... unless you know what to look for or start it up. The saw is noticeably louder, but it's not obnoxiously loud like some other saws I've opened up with much larger ports... kind of a nice balance IMO.

My saw has always leaked a little black crud where the muffler meets the jug, not a lot, but it was noticeable. While I had the muffler off I wanted to find out what was causing this 'leak'. Placing a straight edge over the flange of the muffler, I found it had a couple of low spots, the worst being on the top where I was seeing the black build up. The flange area on the muffler is fairly thick steel, so I took a file to the flange to level it off. After filing it for a minute or two, you can clearly see the low spots in the pic below... and this was after I had already removed some material...






I filed it down until these low areas were almost completely gone and then reassembled everything. After starting the saw, I did not see anything coming from this location, but time will tell. Although, I'd be surprised to see another leak there.

I also installed a 8 pin sprocket and converted over from .404" to .375" chain. Pretty straight forward, but I did screw something up... I was cold and rushing to get back in the house while doing the final reassembly. In my rushing, I stepped on the bar plate and really disfigured it. I tried reshaping it, but it needs to be replaced now. Dummy...

So how does the saw run? I wish I had more time to play with it before I had to cleanup. I went ahead and made a couple of cuts anyway and it's like a totally different saw. It really rips now! It's so nice not hearing that limiter banging away. With the unlimited coil it now seems to run like it should, before hand you had to really put a lot of pressure on the saw to keep it bogged and below the limiter. I need to get the bar plate replaced and spend some more time running it. I'll have to make an effort to watch the spark plug and try to keep the revs at a reasonable level with no load on the saw. All this only took a few hours with me tinkering around and cleaning everything as I went. I though about doing some porting and dropping the jug, but I decided against doing so for now since it already has plenty of snot. I can tell you its seems to run much better now and if nothing else, it should be much more fun to use (assuming it stays glued together  ). The parts cost me just under $70 for everything (coil, 8 pin rim, bar tip, and chain), so far it seems like I got a lot of bang for my money considering I also got a new rim and chain in the process. 

BTW, sorry about the pic quality... I was using my POS phone.


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## blsnelling (Feb 2, 2009)

Excellent information for all the 3120 owners. Any you did this yourself on the cheap too. I love it! Does the saw 4-stroke out of the wood at WOT? I'd trust that before I would the plug color. Plug color is just way to subjective IMHO, although it is another indicator to watch.


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## jack-the-ripper (Feb 2, 2009)

Thanks for sharing. Anyone posting their work like this, is how we gain more knowledge. Now get that video going.


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## albert (Feb 2, 2009)

Good Read and info, another option would be a green 365/372 coil, I think some of them limit @ 13.5k, still higher than I think a 3120 should rev


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## excess650 (Feb 2, 2009)

Did you put a tach on it to see where it tops out? The manual that I looked at listed 11,500-12,500rpm max, no load.


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## brncreeper (Feb 2, 2009)

Where did you purchase the ream for the fixed jet? Or did you just go the numbered drill bit route?


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## Wet1 (Feb 2, 2009)

blsnelling said:


> Excellent information for all the 3120 owners. Any you did this yourself on the cheap too. I love it! Does the saw 4-stroke out of the wood at WOT? I'd trust that before I would the plug color. Plug color is just way to subjective IMHO, although it is another indicator to watch.



Thanks Brad. Honestly I'm still a little afraid to fully let it spin at WOT for long w/o a load on it. I'm not an expert on tuning 2 strokes by ear, but it does sound like it's 4 stroking a little for the very brief amount of time I've let her rip. I need to spend some more time with it... something I don't have much of for the next week or two.  




> Thanks for sharing. Anyone posting their work like this, is how we gain more knowledge. Now get that video going.


Thanks! Sorry no video coming... no DVR. 




> Good Read and info, another option would be a green 365/372 coil, I think some of them limit @ 13.5k, still higher than I think a 3120 should rev


You're probably right about the 3120 reving too high. I didn't look into the 372 coil, they aren't as common. Are they a direct fit? Are all of them limited to 13.5k, or do you have to pick and choose?




> Did you put a tach on it to see where it tops out? The manual that I looked at listed 11,500-12,500rpm max, no load.


I have not put a tack on it yet, but I'm sure it's turning every bit of the 12k spec. I'll try doing this next time I have time to tinker around again. 




> Where did you purchase the ream for the fixed jet? Or did you just go the numbered drill bit route?


Both. I used the numbered bits as an index. I have had the reamers for years, sorry I have no idea where they came from as I bought them off a retired machinist. The jet as you know is brass and very soft. You can probably turn a 57 and 56 bit into the jet by hand (or with pliers) and not remove any excess material if you don't have reamers. Ive done this before with excellent results.


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## blsnelling (Feb 2, 2009)

Take any saw with an adjustable H needle on the carb. Screw it out so that you know it's way rich. Warm the saw up and then go WOT out of the wood. Turn it in until you hear it peak out. Then back up until it's barely not peaked out. That peaked out sound is what we call 2-stroking. That burble you hear when you begin to richen it back up is what we call 4-stroking. You want the saw just on the rich side of peaked out so that there a little 4-stroking. A good time to check is when pulling it out of an extended cut and the engine has max heat in it. BTW, it's much easier to hear on a muffler modded saw.


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## Wet1 (Feb 2, 2009)

blsnelling said:


> Take any saw with an adjustable H needle on the carb. Screw it out so that you know it's way rich. Warm the saw up and then go WOT out of the wood. Turn it in until you hear it peak out. Then back up until it's barely not peaked out. That peaked out sound is what we call 2-stroking. That burble you hear when you begin to richen it back up is what we call 4-stroking. You want the saw just on the rich side of peaked out so that there a little 4-stroking. A good time to check is when pulling it out of an extended cut and the engine has max heat in it. BTW, it's much easier to hear on a muffler modded saw.



Thanks Brad. I actually know how to do it with an adjustable jet, it's just obviously tougher with a fixed jet since you can't make real time adjustments... You really have to work based on your experience, memory, and ear. I did hear a little burbling, so hopefully it's safe.

BTW, good tip on doing the adjustment after making a cut, I've never done that... although I've found killing the saw in a cut is a good way to read the plug as well. Did I mention I hate fixed jet carbs?!?!?!


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## Lakeside53 (Feb 2, 2009)

Great post!


What Brad says about 4-stroking is correct, but.. it still may be too high for the saw (unless you're wanting to be a racer..). Choose the lowest WOT (with a reasonable length bar and chain) you are comfortable with, not the highest the saw will go while "just 4-stroking". I'd stay less than 12k on your saw. it won't affect your cut times materially.


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## pastryguyhawaii (Feb 2, 2009)

Good thread. I'm a big fan of posts that teach me something, that's why I'm here. My Stihl dealer has a 3120 that was given to him as a debt repayment. He put in a new black coil but he says it needs a new carb. I think I could pick it up fairly cheap since he couldn't put it out as a rental and it's not a Stihl. I've always wanted a big Husky.


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## B_Turner (Feb 2, 2009)

Very interesting, and a great post.

It surprises me that the 272 coil started with no changes, as when I tried a black 3120 coil with the EPA flywheel it would not start.

And the magnets on the EPA and non EPA flywheels are roughly 15 degrees different in terms of how they are keyed as I recall.

Also I would have expected the idle timing to be less advanced than your reading.

I applaud your efforts and post and keep us informed of how it works out. You'll wonder how you ever put up with that hammerring. Again, I am a little surprised on the timing, as I would have expected the timing to be more changed when installing the 272 coil.

In terms of the muffler leaking at the cylinder, every one I have seen does that a little. My latest new one was so bad I had them reorder a new muffler on warranty which was even worse. The third muffler was close enough that some lapping got it pretty good.

In swapping the jets, I found in the long run it was quicker and eaiser to take off the top cover and pull the carb off. Makes it so much easier to make sure the gaskets between the carb and cylinder are aligned. The EPA (1.12mm) jet is only $2 at my dealer so easy to try making some different sizes. BWT, the 1.16mm jet isn't available in the US (the non EPA coil and flywheel still are).


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## Wet1 (Feb 2, 2009)

Lakeside53 said:


> Great post!
> 
> 
> What Brad says about 4-stroking is correct, but.. it still may be too high for the saw (unless you're wanting to be a racer..). Choose the lowest WOT (with a reasonable length bar and chain) you are comfortable with, not the highest the saw will go while "just 4-stroking". I'd stay less than 12k on your saw. it won't affect your cut times materially.



Thanks Andy. No racer here (yet!). You bring up a good point. When I do get around to revisiting the saw, I'll check to see what she's turning for max rpm with say a 28" bar. If it's really high (above 13k), I can try richening it up to bring the revs down. If it's below 13k I'll run it and see how the plug looks and see how she preforms... I don't want to foul plugs either. More time is needed at this point, something I don't have right now since I'm on the road.




> Good thread. I'm a big fan of posts that teach me something, that's why I'm here. My Stihl dealer has a 3120 that was given to him as a debt repayment. He put in a new black coil but he says it needs a new carb. I think I could pick it up fairly cheap since he couldn't put it out as a rental and it's not a Stihl. I've always wanted a big Husky.


If you can get it cheap, I'd suggest jumping on it. If you need a big saw, the 3120 is hard to beat. In fact, (Andy don't read this) I think I prefer the 3120 over the 880, especially now that the limiter has been removed.





> Very interesting, and a great post.
> 
> It surprises me that the 272 coil started with no changes, as when I tried a black 3120 coil with the EPA flywheel it would not start.
> 
> ...


B., I believe the black 3120 coil has a different mount/laminate, is this correct? If so, I suspect this is why the other FW would be needed. Actually, I think you could use the stock FW with the black 3120 coil, but you'd have to retime it for that 15° difference. Otherwise it should work just fine.

As noted, the timing with the 272 and the green 3120 coil appear to be nearly identical. What I didn't check was at what point the timing is changed (vs rpm), but this seemed similar as well and I'm sure it would be irrelevant in actual use.

My muffler had a pretty good dip in the flange on the top, probably 8 to 10 thousands. It took me about five minutes with a file to get it level... I'm surprised they never addressed this. Luckily there's plenty of metal there so it can be fixed.

Agreed regarding removing the carb, it's easy and only takes a couple of seconds.


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## blsnelling (Feb 2, 2009)

Wet1 said:


> When I do get around to revisiting the saw, I'll check to see what she's turning for max rpm with say a 28" bar. If it's really high (above 13k), I can try richening it up to bring the revs down. If it's below 13k I'll run it and see how the plug looks and see how she preforms... I don't want to foul plugs either.



Sounds like a valid plan.


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## B_Turner (Feb 2, 2009)

*black and green 3120 coils*











I would have loved to know what your EPA 3120 would have tached WOT with no changes to muffler or jet. 


In terms of max WOT rpm, from what I've read you are playing with fire turning a 3120 at 13k.


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## brncreeper (Feb 2, 2009)

> Both. I used the numbered bits as an index. I have had the reamers for years, sorry I have no idea where they came from as I bought them off a retired machinist. The jet as you know is brass and very soft. You can probably turn a 57 and 56 bit into the jet by hand (or with pliers) and not remove any excess material if you don't have reamers. Ive done this before with excellent results.



For those that don't want to use number bits, the Enco catalog shows a Model 619-1017 (.0440 in.,1.1167mm), and a Model 619-1018 (.0470 in.,1.1938mm). The web site does not pull up the product numbers, the phone number is: 800-873-3626.


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## Wet1 (Feb 2, 2009)

B_Turner said:


> I would have loved to know what your EPA 3120 would have tached WOT with no changes to muffler or jet.
> 
> 
> In terms of max WOT rpm, from what I've read you are playing with fire turning a 3120 at 13k.



Not a chance I wanted to take running an unlimited coil w/o adding more fuel. If the saw is turning higher RPM's more fuel is generally needed. I started it with the 1.12mm jet and it ran and reved up great, but I didn't want to let it run any longer than I needed to.

Looking at that black 3120 coil, I can see why it wouldn't work with the stock FW since it has another pickup. If the non EPA FW has three magnets (which I highly doubt), you be forced to use the matching non-EPA FW. Otherwise, you should be able to retime the EPA FW for that coil, assuming the non EPA FW also only has two magnets. 

I've had a hard time locating info on max RPMs. I know what the factory manual states, but I'm sure this is based on the max RPMs allowable for their limiters. As some point my guess would be the rod will let go, but I have no idea where that point actually is. Romeo or any of the other big bore racers care to comment???


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## Wet1 (Feb 2, 2009)

brncreeper said:


> For those that don't want to use number bits, the Enco catalog shows a Model 619-1017 (.0440 in.,1.1167mm), and a Model 619-1018 (.0470 in.,1.1938mm). The web site does not pull up the product numbers, the phone number is: 800-873-3626.



Nice find. If they are cheap, I wouldn't mind having one of both to have on hand. Are you going to place an order? If so, how much are they?


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## brncreeper (Feb 2, 2009)

Wet1 said:


> Nice find. If they are cheap, I wouldn't mind having one of both to have on hand. Are you going to place an order? If so, how much are they?


They're $23 each, I think I'll wait. About the time I order them someone will come up with a source for a 1.16mm jet. (stevethekiwi?)


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## B_Turner (Feb 2, 2009)

Wet1 said:


> Not a chance I wanted to take running an unlimited coil w/o adding more fuel. If the saw is turning higher RPM's more fuel is generally needed. I started it with the 1.12mm jet and it ran and reved up great, but I didn't want to let it run any longer than I needed to.
> 
> Looking at that black 3120 coil, I can see why it wouldn't work with the stock FW since it has another pickup. If the non EPA FW has three magnets (which I highly doubt), you be forced to use the matching non-EPA FW. Otherwise, you should be able to retime the EPA FW for that coil, assuming the non EPA FW also only has two magnets.
> 
> I've had a hard time locating info on max RPMs. I know what the factory manual states, but I'm sure this is based on the max RPMs allowable for their limiters. As some point my guess would be the rod will let go, but I have no idea where that point actually is. Romeo or any of the other big bore racers care to comment???



My understanding is you don't really want a 3120 spinning up past 12.5k except at the races. If I had an unlimited coil in one of mine, I would be aiming more like 12k max for a safety margin for different fuels, etc. but that's just me as I like to run long bars and lean on them a little for fun.

I don't mind the higher limited coil, except that it doesn't give me ANY information about how I'm jetted. My non EPA 3120 is on the limiter around 11.6 even with the non EPA jet, but I have no idea what it would run unlimited. Seems like StwkS 3120 runs 12.2k even limited and he likes it that way. (He says the black 3120 coil varies from 11,5 to almost 12.5 depending on the instantiation.

Can someone explain to me about coils and why some coils have 2 "pickups" and some 3 pickups? 272, EPA 3120 have 2 and non EPA 3120 coil has 3. So it isn't to do with being limited. Although I've been told I'm a bit limited.....


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## Wet1 (Feb 2, 2009)

brncreeper said:


> They're $23 each, I think I'll wait. About the time I order them someone will come up with a source for a 1.16mm jet. (stevethekiwi?)



Ouch! I believe you should be able to get the the non epa jet through a husky dealer. I noticed what I assume was the correct jet listed when I was looking at an IPL earlier today from an online dealer. I think they wanted about $12 for it there.


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## Cowboy Tom (Feb 2, 2009)

How about pictures of the muffler mod??? I just put a new PC on my 3120 and was thinking about doing the muffler. I would love to see what you've done


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## B_Turner (Feb 2, 2009)

Wet1 said:


> Ouch! I believe you should be able to get the the non epa jet through a husky dealer. I noticed what I assume was the correct jet listed when I was looking at an IPL earlier today from an online dealer. I think they wanted about $12 for it there.



If you ever find a place that actually carries the Walbro 1.16mm jet, let me know. I think the part number is 503 97 67-06.

I had a couple dealers try, including Madsns. I sort of know the main mechanic there and he tried in vain to get 1.16mm jets from their Husky source. His Walbro contact couldn't get them either, so he had to get some smaller jets to drill out when he was trying to work out some issues with a bunch of old new 3120K saws the railroad had found. 

So to my knowledge, the only place that actually has them is ROW (like NZ). Even though they are listed in the IPL for the 3120. I would be glad to be wrong, though.


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## redprospector (Feb 3, 2009)

Wet1 said:


> I've had a hard time locating info on max RPMs. I know what the factory manual states, but I'm sure this is based on the max RPMs allowable for their limiters. As some point my guess would be the rod will let go, but I have no idea where that point actually is. Romeo or any of the other big bore racers care to comment???



I don't know what the factory spec's are on a 3120, but When I'm working mine (which is not very often) I tune it to about 12,000 rpm's. When racing I take her up to about 12800 rpm's. Anything over 13000 makes me nervous.
The crank will let go long before the rod will.
I've got an adjustable carb on mine. There out there, and I highly recomend hunting one down.

Andy


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## pastryguyhawaii (Feb 3, 2009)

I stopped by the Stihl dealer to check out the 3120 he has. He put a black coil on it but can't remember what was originally on there. The saw will fire and run for a few seconds then it dies right out. The carburetor has been cleaned. He doesn't know much about the history but says it doesn't even look broke in. I know this isn't much to go on but I would appreciate any advice on what to check. The serial # is 99 10000 79. I'd really like to pick this up, that thing is a beast!


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## Wet1 (Feb 3, 2009)

Cowboy Tom said:


> How about pictures of the muffler mod??? I just put a new PC on my 3120 and was thinking about doing the muffler. I would love to see what you've done



Sorry I didn't take any while I was doing it (forgot to do so in my frozen state of mind). I'll try to so so next time I'm tinkering with the saw.





> If you ever find a place that actually carries the Walbro 1.16mm jet, let me know. I think the part number is 503 97 67-06.
> 
> I had a couple dealers try, including Madsns. I sort of know the main mechanic there and he tried in vain to get 1.16mm jets from their Husky source. His Walbro contact couldn't get them either, so he had to get some smaller jets to drill out when he was trying to work out some issues with a bunch of old new 3120K saws the railroad had found.
> 
> So to my knowledge, the only place that actually has them is ROW (like NZ). Even though they are listed in the IPL for the 3120. I would be glad to be wrong, though.


I guess I made a poor assumption when I said you might be able to get them from the dealer. 

These are the guys I've used for my Husky parts with a lot of success. You can check with them. I placed an order with them yesterday for a replacement bar/guide plate, but I didn't pursue the jet... although I probably should have.
http://www.russopowerequip.com/parts-browse.asp




> I don't know what the factory spec's are on a 3120, but When I'm working mine (which is not very often) I tune it to about 12,000 rpm's. When racing I take her up to about 12800 rpm's. Anything over 13000 makes me nervous.
> The crank will let go long before the rod will.
> I've got an adjustable carb on mine. There out there, and I highly recomend hunting one down.
> 
> Andy


Great info Andy! 13k was the number I was concerned about seeing as well. I'm now really intersted to see what she's turning in her current configuration. Anything over 13k and I'll open the jet up until it's south of that.

I've had a very hard time finding an adjustable carb. A little birdy (whom you know very well) told me a while ago that the carbs off the 3120k saws have adjustable carbs, but I've now looked at five of them and all had fixed carbs. If you find one, and don't need it yourself, please send me a PM!  




> I stopped by the Stihl dealer to check out the 3120 he has. He put a black coil on it but can't remember what was originally on there. The saw will fire and run for a few seconds then it dies right out. The carburetor has been cleaned. He doesn't know much about the history but says it doesn't even look broke in. I know this isn't much to go on but I would appreciate any advice on what to check. The serial # is 99 10000 79. I'd really like to pick this up, that thing is a beast!


That could be a tough one since being a dealer I would assume he knows what he's doing. Could be an air leak, timing out of wack from his ignition mods, carb, clogged fuel pick up, etc... any number of things. Although, if the price is right I'd jump on it.


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## lovetheoutdoors (Feb 3, 2009)

great thread thanks for the pics and info. now if i get a epa 3120 i know what to do.


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## lovetheoutdoors (Feb 3, 2009)

pastryguyhawaii said:


> I stopped by the Stihl dealer to check out the 3120 he has. He put a black coil on it but can't remember what was originally on there. The saw will fire and run for a few seconds then it dies right out. The carburetor has been cleaned. He doesn't know much about the history but says it doesn't even look broke in. I know this isn't much to go on but I would appreciate any advice on what to check. The serial # is 99 10000 79. I'd really like to pick this up, that thing is a beast!



wouldnt this saw be a 1999? i dont think they epa 'ed them until 2000. someone correct me if im wrong.


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## pastryguyhawaii (Feb 3, 2009)

That could be a tough one since being a dealer I would assume he knows what he's doing. Could be an air leak, timing out of wack from his ignition mods, carb, clogged fuel pick up, etc... any number of things. Although, if the price is right I'd jump on it.[/QUOTE]

He's a good guy but admits he doesn't know much about Husky's. I should have a little cash soon and will go make an offer as is. Then I can break it down and ask some more ?'s on here. If you ever find an adjustable carb that work on those, let me know. I'm not a big fan of fixed jet carbs either.


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## B_Turner (Feb 3, 2009)

pastryguyhawaii said:


> That could be a tough one since being a dealer I would assume he knows what he's doing. Could be an air leak, timing out of wack from his ignition mods, carb, clogged fuel pick up, etc... any number of things. Although, if the price is right I'd jump on it.
> 
> He's a good guy but admits he doesn't know much about Husky's. I should have a little cash soon and will go make an offer as is. Then I can break it down and ask some more ?'s on here. If you ever find an adjustable carb that work on those, let me know. I'm not a big fan of fixed jet carbs either.



Husky upsized the jet size over the years on the 3120, and I am guessing they did it for a reason. So check out that saw for damage, and if you buy it I would go up to a 1.12 mm jet minimum.

On a big saw I don't hate the fix jet as much as I would on a smaller saw (I still don't like them of course), except that with a low limiter you have little idea of whether you are jetted ideally.

In point of fact, with my bigger saws once I get a slightly conservative adjustment that works for me, I very seldom need to change it. With my smaller saws they seem to vary a little more in WOT rpm for some reason - maybe more sensitive to variations in fuel.


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## pastryguyhawaii (Feb 3, 2009)

B_Turner said:


> Husky upsized the jet size over the years on the 3120, and I am guessing they did it for a reason. So check out that saw for damage, and if you buy it I would go up to a 1.12 mm jet minimum.
> 
> On a big saw I don't hate the fix jet as much as I would on a smaller saw (I still don't like them of course), except that with a low limiter you have little idea of whether you are jetted ideally.
> 
> In point of fact, with my bigger saws once I get a slightly conservative adjustment that works for me, I very seldom need to change it. With my smaller saws they seem to vary a little more in WOT rpm for some reason - maybe more sensitive to variations in fuel.



I looked at the saw again today. It does rev fine it just doesn't want to idle. The P/C are good. Apparently the original owner just didn't care for any of his equipment. I don't think it was abused, just neglected. He said he would take $600 for it as is. It's an XP model w/ a full wrap handle, has a marginal bar and chain but I'd put my Stihl bars on it if it's adaptable. Considering the price of a new one that's not too bad. I'm trying to learn more about this model before I buy. I appreciate all the 3120 owner's input.


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## B_Turner (Feb 3, 2009)

pastryguyhawaii said:


> I looked at the saw again today. It does rev fine it just doesn't want to idle. The P/C are good. Apparently the original owner just didn't care for any of his equipment. I don't think it was abused, just neglected. He said he would take $600 for it as is. It's an XP model w/ a full wrap handle, has a marginal bar and chain but I'd put my Stihl bars on it if it's adaptable. Considering the price of a new one that's not too bad. I'm trying to learn more about this model before I buy. I appreciate all the 3120 owner's input.



With all the unknown factor I would not pay $600 unless it ran like a top. The big saws can get really expensive in terms of parts.


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## excess650 (Feb 3, 2009)

B_Turner said:


> With all the unknown factor I would not pay $600 unless it ran like a top. The big saws can get really expensive in terms of parts.



The counter to that is that BIG saws are really uncommon in some areas. I saw an 088 with 48" bar this summer and walked away from it with a $1200 price tag on it. When I saw a 3120 advertised locally for more reasonable $, I had to go and look.


I agree that the bigguns can be $$ to fix, but his sounds like a not too serious problem. Things that come to mind are carb kit fuel filter, airfilter, and clutch.

Price is generally dictated by supply and demand.


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## B_Turner (Feb 3, 2009)

excess650 said:


> The counter to that is that BIG saws are really uncommon in some areas. I saw an 088 with 48" bar this summer and walked away from it with a $1200 price tag on it. When I saw a 3120 advertised locally for more reasonable $, I had to go and look.
> 
> 
> I agree that the bigguns can be $$ to fix, but his sounds like a not too serious problem. Things that come to mind are carb kit fuel filter, airfilter, and clutch.
> ...



True, but there is much more demand for used 880s than 3120 and the price usually reflects that.


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## pastryguyhawaii (Feb 3, 2009)

B_Turner said:


> With all the unknown factor I would not pay $600 unless it ran like a top. The big saws can get really expensive in terms of parts.



Thanks. I'm sure it could add up quite quickly. I do need to buy a saw for business expenses this year but I'll take my time. There's a select few I would like.


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## B_Turner (Feb 3, 2009)

pastryguyhawaii said:


> Thanks. I'm sure it could add up quite quickly. I do need to buy a saw for business expenses this year but I'll take my time. There's a select few I would like.



From time to time I've seen pretty nice 3120s for sale for $500 to $700. 

It's like used pianos, you never see a good deal when you are actually wanting one.


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## pastryguyhawaii (Feb 6, 2009)

Just an FYI. Bailey's can get the adjustable carb for the 3120 for $155.


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## B_Turner (Feb 6, 2009)

pastryguyhawaii said:


> Just an FYI. Bailey's can get the adjustable carb for the 3120 for $155.



Are you sure? Is it a Walbro just like the original 3120 adjustable carb (1989?)? Heck, a flywheel for a 3120 cost more than that.

Do you have a part number? If true (I am from Missoura), I would probably buy one just for fun.


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## B_Turner (Feb 6, 2009)

pastryguyhawaii said:


> Just an FYI. Bailey's can get the adjustable carb for the 3120 for $155.



I sent the person you talked to an email and heard back from him. He said they can't get that carb for emmision reasons. I'm sort of confused of why he told you they had such a carb available.



They told me they couldn't order the Husky black coil and flywheel a while back too and I wonder if it is because of CA stricter emmision policy. Because you can get those parts anywhere else.


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## albert (Feb 7, 2009)

Did you get a chance to tach it with the jet drillred? just wondering how it went, thanks


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## brncreeper (Feb 7, 2009)

B_Turner said:


> I sent the person you talked to an email and heard back from him. He said they can't get that carb for emmision reasons. I'm sort of confused of why he told you they had such a carb available.
> 
> 
> 
> They told me they couldn't order the Husky black coil and flywheel a while back too and I wonder if it is because of CA stricter emmision policy. Because you can get those parts anywhere else.



I don't think that's true about the emmision policy, at least on parts. I recently purchased an HT-7A carb for a 084/088($174 new), it takes a few weeks but a dealer can get it.


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## B_Turner (Feb 7, 2009)

brncreeper said:


> I don't think that's true about the emmision policy, at least on parts. I recently purchased an HT-7A carb for a 084/088($174 new), it takes a few weeks but a dealer can get it.



I tend to agree, as coil flywheel parts for the 3120 they said they couldn't get, you got from your dealer and then later I ordered them here no problem (although I only reached dead ends on the 1.16mm jet - which I bought from STKW). I am giving Bailys the BOTD by saying maybe it's a CA thing.

If I could order a 3120 carb with the adjustable jet, I think I would if it were in the ballpark of the Stihl carb you mention. Just for a future project saw.

Maybe next time you are at your Husky dealer you can ask him if he thinks he can order a adjustable Walbro for a 3120 just for another opinion.


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## brncreeper (Feb 7, 2009)

B_Turner said:


> I tend to agree, as coil flywheel parts for the 3120 they said they couldn't get, you got from your dealer and then later I ordered them here no problem (although I only reached dead ends on the 1.16mm jet - which I bought from STKW). I am giving Bailys the BOTD by saying maybe it's a CA thing.
> 
> If I could order a 3120 carb with the adjustable jet, I think I would if it were in the ballpark of the Stihl carb you mention. Just for a future project saw.
> 
> Maybe next time you are at your Husky dealer you can ask him if he thinks he can order a adjustable Walbro for a 3120 just for another opinion.



He tried to get the 1.16 jet, but could not. I’ll ask him sometime about the carb (got a part number?), I just seen him yesterday. Picked up my new OEM piston, rings, and base gasket for the 3120. Total on parts came to $98.

edit: he had one 372xp left, price was $700.


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## B_Turner (Mar 2, 2009)

Wet1, how's the 3120 with the stock EPA flywheel and 272 coil doing?


What jet size did you end up with?


I'm still a little confused, as EH has posted in the past that the flywheel needs to be retimed with a 272 coil....But your results say otherwise.


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## Wet1 (Mar 2, 2009)

B_Turner said:


> Wet1, how's the 3120 with the stock EPA flywheel and 272 coil doing?
> 
> 
> What jet size did you end up with?
> ...



Funny you ask, I finally got around to running it on Saturday. I didn't have any big wood to buck, so I threw a 28" bar on it (with an 8 pin) to cut 24" white oak, which did an okay job of loading the saw with a little pressure on it. I threw the tach on it with the 28" b&c, it was turning right around 13.4k-13.5k at WOT out of the wood. A little high for my comfort, but I used it anyway since I knew it would drop down in the cut. I made about 20 cuts with it and then shut it down at WOT so I could later read the plug. 

I pulled the spark plug yesterday to see how it looked, it appeared a little leaner than I'd like (although not too bad), so I'll be reaming out the jet a little more before she goes out for another workout. Hopefully this will drop the revs down a hair at the same time. 13.5k wasn't enough to really frighten me, but I'd feel pretty safe if it was around 13.2k or so. Once I get the plug looking nice, I'll try to report back as to what I finally ended up with on the main jet sizing.

Regarding the timing, I think it depends on the coil. The 272 coil I had on hand dropped right in and the timing was exactly where it was with the factory 2005 EPA FW/coil. I would not expect this to always be the case with all 272 coils, so check before and after if someone out there is considering doing this change. Also noteworthy, I didn't have to notch the case for the 272 coil, as I feared.


I have to tell you this thing is is pretty LOUD WFO after doing the muffler mod, and boy does it scream now!!! You can really feel it in your chest when she's doing her thing. It's a totally different saw now after doing these mods. I haven't compared it to the 880 yet, but my guess is it will walk the (stock) 880 now by a significant margin. It really is hard to believe this is the same saw and that it woke up this much with a few cheap and simple mods...

I have a a couple of projects I still need to get to first, but if I have the time (and I never seem to), I'd like to drop the jug, do some porting, and advance the timing a few degrees. Not that it really needs more power (it's pretty impressive as it sits), but you know how it goes. :hmm3grin2orange:


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## B_Turner (Mar 2, 2009)

Wet1 said:


> Funny you ask, I finally got around to running it on Saturday. I didn't have any big wood to buck, so I threw a 28" bar on it (with an 8 pin) to cut 24" white oak, which did an okay job of loading the saw with a little pressure on it. I threw the tach on it with the 28" b&c, it was turning right around 13.4k-13.5k at WOT out of the wood. A little high for my comfort, but I used it anyway since I knew it would drop down in the cut. I made about 20 cuts with it and then shut it down at WOT so I could later read the plug.
> 
> I pulled the spark plug yesterday to see how it looked, it appeared a little leaner than I'd like (although not too bad), so I'll be reaming out the jet a little more before she goes out for another workout. Hopefully this will drop the revs down a hair at the same time. 13.5k wasn't enough to really frighten me, but I'd feel pretty safe if it was around 13.2k or so. Once I get the plug looking nice, I'll try to report back as to what I finally ended up with on the main jet sizing.
> 
> ...



Thanks for the report. EH also reported he needed to notch the case with a 272 coil because of the wire and you didn't, so there must be some sort of variations either in saws or coils. The wire from a green and black 3120 coils are at vary different angles, but I think it may just be because of different "thicknesses" of each coil.


Based on what I've read, I'd get a bigger jet on that sucker very soon. I bought a couple spare 1.12mm jets to have on hand in my last order, and they were only $2.

On a slightly different note I am starting to keep my eye out for a beater 3120 and maybe have someone do some mild porting and such without opening up the muffler (extra noise bothers me physically).

Both my 3120s (and 880) are too new and pretty (and expensive) to start messing with yet.


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## blsnelling (Mar 2, 2009)

Is it 4-stroking at all at 13,500?


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## Wet1 (Mar 2, 2009)

blsnelling said:


> Is it 4-stroking at all at 13,500?



I thought it was, although I'm not an expert on tuning 2 strokes by ear, but by looking at the plug I'm not so sure. Either way, I know it could be a little richer based on the plug appearance. Plus, lower revs and more margin of safety certainly sound like a good idea when in doubt.


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## Wet1 (Mar 2, 2009)

B_Turner said:


> Thanks for the report. EH also reported he needed to notch the case with a 272 coil because of the wire and you didn't, so there must be some sort of variations either in saws or coils. The wire from a green and black 3120 coils are at vary different angles, but I think it may just be because of different "thicknesses" of each coil.
> 
> 
> Based on what I've read, I'd get a bigger jet on that sucker very soon. I bought a couple spare 1.12mm jets to have on hand in my last order, and they were only $2.
> ...


I wish I could tell you if the saws or coils are different, but I know this combo worked (2005 saw a you can see the coil PN in the pics) for me, although Ed is a very sharp guy so I would certainly listen to anything he told you.

If you don't mind me asking, where did you get the $2 jets? Do you have the part number on hand? I'd like to have an extra (or two) on hand as well.

I hear you on modding a new saw. While mine is in excellent condition, I believe I still have less than $650 into this saw, including the mods. Still a lot of money I guess, but that's peanuts compared to the cost of a new replacement. Since I don't use this saw for my livelihood, and I have other large saws on hand should I need one, I'm not overly worried about modding this saw and having something happen to it because of something I've done (although hopefully this doesn't happen).


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## B_Turner (Mar 2, 2009)

Wet1 said:


> I wish I could tell you if the saws or coils are different, but I know this combo worked (2005 saw a you can see the coil PN in the pics) for me, although Ed is a very sharp guy so I would certainly listen to anything he told you.
> 
> If you don't mind me asking, where did you get the $2 jets? Do you have the part number on hand? I'd like to have an extra (or two) on hand as well.
> 
> I hear you on modding a new saw. While mine is in excellent condition, I believe I still have less than $650 into this saw, including the mods. Still a lot of money I guess, but that's peanuts compared to the cost of a new replacement. Since I don't use this saw for my livelihood, and I have other large saws on hand should I need one, I'm not overly worried about modding this saw and having something happen to it because of something I've done (although hopefully this doesn't happen).



I bought the 1.12mm jet from a husky dealer for $2 each. You may be able to get bigger jets from a Walbro dealer, but as far as I could tell the 1.16mm (non EPA jet) size was not available in the US at all.

1.12 jet part # 503 97 67-06 (I believe)

In terms of cost, I have well over twice into each of my 3120s as you do as I bought them new and then bought the non EPA flywheel and coil. That's why I am keeping a lookout for a good deal on a used one to play with.


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## Wet1 (Mar 2, 2009)

B_Turner said:


> I bought the 1.12mm jet from a husky dealer for $2 each...
> 1.12 jet part # 503 97 67-06 (I believe)



I called my local husky dealer, he didn't come up with anything using that part number. He wants me to give him my serial number (tomorrow) and said he'll call husky and see what they can come up with. It would be nice to start with a factory 1.16 jet, but just having a spare 1.12 kicking around would be fine for me. I'll let you know what he comes up with.


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## MCW (Mar 2, 2009)

My 3120 has got an adjustable Walbro carb (WG-7A or WG-10 according to the manual) but a 2008 Australian model. If anybody wants a price on anything in particular let me know. I'm on good terms with the Husky dealer and our dollar is s#*t compared to yours! It could take some time though, it took 7 weeks for my 3120 to arrive. According to the manual its got 12,000rpm limit too? Video below for those interested. They're an awesome saw and this was some pretty hard wood...

http://www.youtube.com/watch?v=glepRIvmw_g


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## B_Turner (Mar 2, 2009)

Wet1 said:


> I called my local husky dealer, he didn't come up with anything using that part number. He wants me to give him my serial number (tomorrow) and said he'll call husky and see what they can come up with. It would be nice to start with a factory 1.16 jet, but just having a spare 1.12 kicking around would be fine for me. I'll let you know what he comes up with.




I guess that is the non epa jet. So I think the 1.12 jet is

503 97 67-05 

and is still available.


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## Wet1 (Mar 2, 2009)

I'm sure B. and I would both be interested in an adjustable carb. Please shoot us a PM with down-under pricing if you get a chance.

Thanks!


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## Wet1 (Mar 2, 2009)

B_Turner said:


> I guess that is the non epa jet. So I think the 1.12 jet is
> 
> 503 97 67-05
> 
> and is still available.



Thanks, I'll see what he says tomorrow.


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## B_Turner (Mar 2, 2009)

MCW said:


> My 3120 has got an adjustable Walbro carb (WG-7A or WG-10 according to the manual) but a 2008 Australian model. If anybody wants a price on anything in particular let me know. I'm on good terms with the Husky dealer and our dollar is s#*t compared to yours! It could take some time though, it took 7 weeks for my 3120 to arrive. According to the manual its got 12,000rpm limit too? Video below for those interested. They're an awesome saw and this was some pretty hard wood...
> 
> http://www.youtube.com/watch?v=glepRIvmw_g



All the manuals say 12k, even the 9.7k US models (EPA).

No offense, but are you sure the HS is adjustable on your 3120? (not just idle and low speed?) That fooled silogger for a short while until he looked closer.

I've was not aware an adjustable HS carb 3120 was available anywhere. My IPL shows the WG7 and 8 both fixed jet. But when I googled and found articles talking about walbro carbs on powered paraglider sites, it seems like certain carbs had adjustable HS jets. Also the Walbro literature says WG available in adjustable HS. So now I'm totally confused what is available and might work for a 3120.

I hear this little voice....(Andy) Just get an 880 and be done with it.....


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## MCW (Mar 3, 2009)

B_Turner said:


> All the manuals say 12k, even the 9.7k US models (EPA).
> No offense, but are you sure the HS is adjustable on your 3120? (not just idle and low speed?) That fooled silogger for a short while until he looked closer.
> So now I'm totally confused what is available and might work for a 3120.


Good to know that all the manuals say that mate. The manual is pretty lame actually! 
Spoke to the local Husky guy today over the phone and he said he's seen both adjustable jets (H/L) and fixed jets on the larger Huskys although mine is only the 3rd 3120XP he's sold in over 10 years so he's not 100% sure. I just checked my saw a bit closer and you're right - no adjustable high jet. Only low and idle.
I'm going to ring Husky Australia to ask them whats available over the next few days. Husky dealer reckons a whole replacement carby is likely to be around USD$140-150. You guys in the US could probably land one there for around USD$180 if they are available.


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## B_Turner (Mar 3, 2009)

MCW said:


> Good to know that all the manuals say that mate. The manual is pretty lame actually!
> Spoke to the local Husky guy today over the phone and he said he's seen both adjustable jets (H/L) and fixed jets on the larger Huskys although mine is only the 3rd 3120XP he's sold in over 10 years so he's not 100% sure. I just checked my saw a bit closer and you're right - no adjustable high jet. Only low and idle.
> I'm going to ring Husky Australia to ask them whats available over the next few days. Husky dealer reckons a whole replacement carby is likely to be around USD$140-150. You guys in the US could probably land one there for around USD$180 if they are available.



I will be curious, although I still am guessing he's wrong and in the 3120 it's all fixed HS jet.

I see online Walbro carbs available, but the hard part would be to know exactly which configuration would drop onto the 3120.

What color is the coil on yours, green or black? You can look through the cover and see it on the recoil side.


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## Wet1 (Mar 3, 2009)

B_Turner said:


> I will be curious, although I still am guessing he's wrong and in the 3120 it's all fixed HS jet.
> 
> I see online Walbro carbs available, but the hard part would be to know exactly which configuration would drop onto the 3120.
> 
> What color is the coil on yours, green or black? You can look through the cover and see it on the recoil side.



I'm sure you're right, they should all be fixed jet carbs on these newer saws. I believe his saw would most likely be a ROW saw, it should have the black coil with the higher 12k limit.


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## MCW (Mar 3, 2009)

B_Turner said:


> I will be curious, although I still am guessing he's wrong and in the 3120 it's all fixed HS jet





Wet1 said:


> I'm sure you're right, they should all be fixed jet carbs on these newer saws. I believe his saw would most likely be a ROW saw, it should have the black coil with the higher 12k limit.


 
You are probably right regarding the fixed H jet. The local Husky guy doesn't sell a hell of a lot of bigger models and his memory may be failing him! Mine does have the black coil too.


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## jaywebb916 (Mar 19, 2009)

*3120 xp*

hey guy's
I'm new to this so please be patient. first off I hope I'm in the right place. I have an older husky 3120xp. it has new top end and a complete carb rebuild. the saw syarts and runs but it feels like it should rev alot higher. it doesn't have that wide open feel of a nice running two stroke. any suggestions would be welcome...thanks


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## jaywebb916 (Mar 19, 2009)

*3120 xp*

hey guy's
I'm new to this so please be patient. first off I hope I'm in the right place. I have an older husky 3120xp. it has new top end and a complete carb rebuild. the saw starts and runs but it feels like it should rev alot higher. it doesn't have that wide open feel of a nice running two stroke. any suggestions would be welcome...thanks


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## Wet1 (Mar 19, 2009)

What color is the coil?


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## jaywebb916 (Mar 19, 2009)

black


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## Wet1 (Mar 19, 2009)

Well, that is the higher limiting coil. What's it turning for max rpm?


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## jaywebb916 (Mar 19, 2009)

do not know. I'll need to but a tach tool. is a tool I could find at sears or autozone?


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## jaywebb916 (Mar 20, 2009)

the tach on my 3120 is bouncing from 10,250 to 10,440......at wide open. it just doesn't feel crisp. any help would be appreciated.


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## MCW (Mar 21, 2009)

Wet1 said:


> Well, that is the higher limiting coil. What's it turning for max rpm?



12,000RPM for the black coil I think?


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## B_Turner (Mar 21, 2009)

If your tach reading is at all steady, then you are not on the limiter. When on the limiter the tach will read nonsense -- like it will jump around and read 4k etc as the spark is interrupted.


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## jaywebb916 (Mar 21, 2009)

why would I only read 10 to 10-5 at full throttle?


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## Chad Schlise (Mar 21, 2009)

Great info, and also a good way to turn the 3120 into a chainsaw instead of a air conditioner.


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## B_Turner (Mar 21, 2009)

jaywebb916 said:


> why would I only read 10 to 10-5 at full throttle?



I'll leave that to the saw techs to really answer but it seems to be like it's probably a fuel thing. If it were an adjustable carb (which it probably isn't) then I would say it was adjusted way too rich.

Did they mess with the jet, drilling it out too much (I think it was brncreeper that had the same issue after he accidentally drilled his jet to 1.6mm reather than 1.16mm.)

Air filter?


Flywheel slipped on keyway?

Tach wonky?


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## jaywebb916 (Mar 21, 2009)

I wish I knew. I just pulled the plug and it's really black,which I think indicates way rich???? I rebuilt the carb myself with all new parts. I guess I could fool with the H and L settings but I'm terrible with those things. I'm going to check the compression right now. thanks.


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## Wet1 (Mar 23, 2009)

jaywebb916 said:


> I wish I knew. I just pulled the plug and it's really black,which I think indicates way rich???? I rebuilt the carb myself with all new parts. I guess I could fool with the H and L settings but I'm terrible with those things. I'm going to check the compression right now. thanks.



Sorry, I didn't see this. Based on what you've written, it sounds like the saw is running excessively rich. Check to see if your carb has a high speed jet adjustment, most do not, but yours might if it's old enough. If so, turn it in some until it starts four stroking or hits the limiter. You should be able to reach around 11.6k (+/-) with that coil in it. If you do not have an adjustable high jet, it sounds like someone has reamed out (or exchanged) the factory jet... and went too far doing so. Assuming it's a fixed jet, I'd start with a factory 1.12mm jet and go from there. 

All this is assuming you didn't screw anything up when rebuilding the carb. 

Good luck.

BTW, you might want to make sure it has the correct plug in it as well.


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## ASEMASTER (May 28, 2009)

*3120k*

Hi guys I have 3120K at work and it needs a new upper end .I know this saw has no oiling ability but would it be worth fixing to do some racing or milling with water as a lube (this does work as I use it on my other saw).
I am a good mechanic and would like to take all this info and make one screaming saw out of this if you think it would work .. the saw will be free but it has been blown up.


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## ritchie.426 (Jun 19, 2009)

*3120 carbs*

Hey guys, I had two of these brought in from oz in bits, 1 had an adjustable hs, the other fixed. Im sure the adjustable was a 95, the other is a 98. I rebuilt the 95 stock with oem bits and put the fixed carb on it. Both have black coils. With the fixed carb on it it ran like a dog. I swapped them over and it ran alot better but still had room for improvement. Ive sold the 95 and will try and track it down to see if I can get the carb model no. Ive asked around and no one has heard of a hs adjustable carb for these, but trust me they do exsist!!

The 98 is getting a rebuild at the mo, polished the cases so far, have one other mod to make to make to them then will throw the bottom end together. I work at a husky shop so will look on epc tomorrow regarding the jets and perhaps earlier carbs.


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## B_Turner (Jun 19, 2009)

ritchie.426 said:


> Hey guys, I had two of these brought in from oz in bits, 1 had an adjustable hs, the other fixed. Im sure the adjustable was a 95, the other is a 98. I rebuilt the 95 stock with oem bits and put the fixed carb on it. Both have black coils. With the fixed carb on it it ran like a dog. I swapped them over and it ran alot better but still had room for improvement. Ive sold the 95 and will try and track it down to see if I can get the carb model no. Ive asked around and no one has heard of a hs adjustable carb for these, but trust me they do exsist!!
> 
> The 98 is getting a rebuild at the mo, polished the cases so far, have one other mod to make to make to them then will throw the bottom end together. I work at a husky shop so will look on epc tomorrow regarding the jets and perhaps earlier carbs.



My understanding was that the adjustable HS on the 3120 was gone by 95. I think the saw began around 89 and the fixed carb came in a couple years later.

I had hoped that walbro sold the adjustable HS carb for some other application still, but have not found one available new.

Also as far as I can tell, for some reason in the US the 3120 OEM non epa jet (1.16mm) cannot be found in the us (even through Walbro), although it can be easily had in NZ (thanks stevethekiwi).

The 3120 non epa coil (black) and flywheel are still readily available here new through husky, just not the jet. (Course one can ream the 1.12 jet bigger.)


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## dbabcock (Jun 19, 2009)

*Getting rid of the 3120 rev limit*

Check out my thread, "Getting Rid of the 3120 Rev Limit" from a long time ago.


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## rupedoggy (Jun 19, 2009)

Wow speaking of a long time ago. "Daniel Boone Babcock" how the heck are you? Flying any Helos lately? Mike


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## blsnelling (Sep 11, 2009)

An excellent read here. I'm bumping this since I will be working on a 3120 soon.


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## B_Turner (Sep 11, 2009)

blsnelling said:


> An excellent read here. I'm bumping this since I will be working on a 3120 soon.



I'd love to hear what sort of gains you get before you muffler mod.

I know gains will be muted, but I'm very curious anyway as I"ve considered having one of my 3120s mildly ported without touching the muffler.

Yeah, I know I'm a broken record on this....

One of the challenges will be jetting the HS esp if it has a rev limited coil. I'd suggested buying an extra jet as they are less than $3.

ALso I hope you do progessive vids as you often do.


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## blsnelling (Sep 11, 2009)

This saw is about 4 years old. It was ported, etc, when new. An offset flywheel key was used, which sheared right away, and it hasn't run right since. So it's a brand new saw that's been setting for 4 years. Hopefully I won't find a bag of worms and a carb cleaning and it'll be back in shape. I don't yet know if it has the low RPM coil or not. I can't see leaving it with a 9,600 RPM coil. If ported, it should consistently pull well more than that in the wood.


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## B_Turner (Sep 11, 2009)

blsnelling said:


> This saw is about 4 years old. It was ported, etc, when new. An offset flywheel key was used, which sheared right away, and it hasn't run right since. So it's a brand new saw that's been setting for 4 years. Hopefully I won't find a bag of worms and a carb cleaning and it'll be back in shape. I don't yet know if it has the low RPM coil or not. I can't see leaving it with a 9,600 RPM coil. If ported, it should consistently pull well more than that in the wood.



Even my stockers like best to pull 9.5- 10.2 in the wood, loaded with a big bar. Right above where the green coil cuts out!

I think the main reason the 3120 gets such a bad rap is that low limit since 2000. Otherwise they are a smooth, and strong saw.


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## brncreeper (Sep 11, 2009)

Mine is on it's way back from timberwolf, I should get it in a few days. I can't wait!:hmm3grin2orange:


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## blsnelling (Sep 11, 2009)

brncreeper said:


> Mine is on it's way back from timberwolf, I should get it in a few days. I can't wait!:hmm3grin2orange:



Do you know what he did with the limiter and carb?


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## brncreeper (Sep 11, 2009)

I replaced the limited 9500 rpm “green” coil before I shipped it, I sent along a spare WG6 carburetor for him to mod. I believe besides boring the carbs throat he drilled the jet to get the correct spark plug color.


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## capeferrelo (Oct 7, 2009)

*Walbro WG8, etc...*

Hi All,

I've been considering a 3120 as a milling powerhead, and wondering about finding a pre-EPA unit, or fiddling with a current one, or just seeing if the stock RPM and fuel limits will work for milling.

So, the thread has been very interesting. I have been looking up the WG8 carbs online, and see they are used in a lot of different applications such as paragliders, etc...I am sure some or most of you know that already. 

I did find some interesting sites, notably Walbro's website which lists a new WG8 for aftermarket sale, with HS adjuster (presumably for those users who have gliders or karts or whatever) for $96.31 :
http://wem.walbro.com/walbro/partnumbersearch.asp?ItemNumber=WG-8-1&ManuItemNumber=&submit1=Go

http://wem.walbro.com/walbro/product2.asp?partnum=WG-8-1&Series=WG

Also found a site for a powered hanglider which has a nice write-up on WG8 disassembly:
http://www.wind-drifter.com/technical/wg8walbro.php

I have not seen the fixed carb in a 3120, but if the HS adjuster screw is simply blocked off with a plug, I would imagine that someone with some experience in modding carbs, especially something like Webers, or a good speed shop, could easily modify the unit to accept an adjuster (which appear to be availble from Walbro, or maybe cannibalized from another Walbro carb.

If noone's seen these sites before, I hope you enjoy...and if anyone is looking at their 3120 carb, can you verify the adjust port being simply blocked, or never machined? Again, I think a good machinest could fix that.

I would like to hear ideas, feedback, etc...I've had conflicting opinions about what is better as a milling head....395 or 3120. I have a 288xp that I love and use for felling and bucking (though I am always in the mood for another, or a 262 or 272 if anyone out there is unloading saws in the future), but I would rather keep that saw for cutting, not milling.

Cheers,

Steve


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## boo (Mar 8, 2010)

is the WG-6 the carb to use?
Walbro shows the WG-3-1 with part#102-3077 and WG-5-1 with part#102-3062.
Both are for partlist#40 (HS adjustable)
http://wem.walbro.com/walbro/group2.asp?FamilyName=WG


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## ritchie.426 (Mar 10, 2010)

*When I got the 3120 going*

it was running 13500 (from memory) with a 28" bar. I run it at 13000 free reving, sits on 12 in a log, seems to handle it well.

Goes hard now.....!!

Got a couple of macrocarpas to drop shortly so I will put the 36" bar on and see how she goes, might be able to ge t a vid as well!:greenchainsaw:


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## blsnelling (Mar 10, 2010)

You will not find a new WG carb with a H needle. The WG-8 was mentioned a couple posts up. If you open the exploded view, and go down to the high speed needle, you'll see there's just -----, no PN. It does not have one. There is not a plug in the carb, it's cast solid. Additionally, if there were a H needle there, it would be directly covered by the air filter base, hitting the needle where it comes out of the carb. So even if you find an old carb with a H needle, it will not likely just bolt onto your 3120.

Your best bet is to keep reeming out a jet until you get it right. It's time consuming, but very easy to do.


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## gogo_78 (Mar 6, 2012)

Does anyone know any source for 1.16 non epa jets nowadays?


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## [email protected] (Dec 31, 2018)

Any updates on parts availability in the US for these mods?


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