# spark, gas, compression, but still won't start, what next??



## cityboy

Got the cylinder plug for my 357xp to replace the auto decomp valve, and the compression seems good. I know, I need to do a compression test to be sure, but it feels like the compression is good and I can suspend the saw (with bar attached) by the starter rope and it holds. I don't have a compression gauge, so that's why I don't have a reading, but I'll get it measured as soon as I can. Assuming that checks out OK, what else should I try next? I have spark, and after repeated cranking the plug is moist with fuel, so I think I have spark, fuel, and compression, but it won't even sputter, nothing at all.

I thought about pulling the carb and doing a rebuild, since that's fairly easy to do but I'm at a loss as to why this saw ran fine one day, then two weeks later wouldn't even sputter.


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## Fish

I would drain out all the fuel, and pull until the cylinder dries out, then do not refuel, but prime a little to see if it hits then dies, then
you will know it is just flooded or the gas was bad.
If still nothing, look at the flywheel key.


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## zxcvbob

I had a saw like that recently; the problem was the gas cap gasket. Years of oxygenated gasoline had rotten the rubber just enough that the tank wouldn't pressurize. I put a new O-ring on it and the saw started right up and runs better than it has in years. 

I know it's a long shot, especially since you said it's getting gas. But if your saw has a vented gas cap make sure the vent is open, and if it has a pressure cap make sure that it seals.


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## lfnh

Disconnect kill switch wire at coil.
Check plug wire for burns/cuts.
A new spark plug, if you haven't.


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## JustinM

cityboy said:


> Got the cylinder plug for my 357xp to replace the auto decomp valve, and the compression seems good. I know, I need to do a compression test to be sure, but it feels like the compression is good and I can suspend the saw (with bar attached) by the starter rope and it holds. I don't have a compression gauge, so that's why I don't have a reading, but I'll get it measured as soon as I can. Assuming that checks out OK, what else should I try next? I have spark, and after repeated cranking the plug is moist with fuel, so I think I have spark, fuel, and compression, but it won't even sputter, nothing at all.
> 
> I thought about pulling the carb and doing a rebuild, since that's fairly easy to do but I'm at a loss as to why this saw ran fine one day, then two weeks later wouldn't even sputter.


 
Have you tried putting a little mix right in the spark plug hole? The fact that your plug is a little moist suggests some mix is getting through, but its possible its not enough. If you squirt a little fuel into the plug hole & then get a sputter when you try to start it, then you know its a fuel delivery problem & you can isolate the issue to either fuel getting to, or from, the carburetor.


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## rms61moparman

Change the plug first!
Then change it again, they are cheap!

If you have fuel, compression and ignition.......at the right time......it has to run, it has no option!
As Fish said check the flywheel key and the air gap between the coil and magnet if the above doesn't solve the problem.
I have seen both of those produce a good spark when the plug wasn't installed and NOTHING when you put the plug back in.


Mike


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## lfnh

+1


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## mayhem100

I just got my craigslsit $75 346XP running by pulling the plug and letting the flooded chamber dry out and regapping the plug. I got spark on my plug too, but the gas was set to double the factory spec...tightened it up, some fresh fuel and it fired on the third pull.

Seems overly obvious I know, but if I can get this lucky, anyone can!


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## scottr

cityboy said:


> Got the cylinder plug for my 357xp to replace the auto decomp valve, and the compression seems good. I know, I need to do a compression test to be sure, but it feels like the compression is good and I can suspend the saw (with bar attached) by the starter rope and it holds. I don't have a compression gauge, so that's why I don't have a reading, but I'll get it measured as soon as I can. Assuming that checks out OK, what else should I try next? I have spark, and after repeated cranking the plug is moist with fuel, so I think I have spark, fuel, and compression, but it won't even sputter, nothing at all.
> 
> I thought about pulling the carb and doing a rebuild, since that's fairly easy to do but I'm at a loss as to why this saw ran fine one day, then two weeks later wouldn't even sputter.


 
You say you have spark, a fuel moist plug then you say you think you have spark. I'd suggest you try a known good spark plug set to the correct gap.


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## russhd1997

Remove the muffler and look at the piston. I had the same thing happen to one of my saws. It felt like it had compression with the plug in it but it didn't have enough. The exhaust side of the piston was scored.


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## cityboy

rms61moparman said:


> Change the plug first!
> Then change it again, they are cheap!
> 
> If you have fuel, compression and ignition.......at the right time......it has to run, it has no option!
> As Fish said check the flywheel key and the air gap between the coil and magnet if the above doesn't solve the problem.
> I have seen both of those produce a good spark when the plug wasn't installed and NOTHING when you put the plug back in.
> 
> 
> Mike


 

I haven't checked the ignition timing, and if its off that could explain what I'm seeing. I'm totally new to chainsaw repair, so I need a little coaching. Is the flywheel key a fixed woodruff key type of arrangement, where it would have had to physically break or fall out to change the timing, or is there something else that's adjustable that I need to check for proper alignment?

I'm pretty sure the air gap is correct, but I need to get a non-magnetic 0.3mm gauge to make sure. I used a piece of cardboard and micrometer, and it seemed to be just about right. Or, can I just put a regular metal feeler gauge in there? 

Regarding some of the other suggestions:

Fuel tank pressurization: 

I'm not sure exactly how to check this, but have done this so far: Removed gas cap, put it back in. Removed fuel supply line from carb, no gas shot out. Blew into supply line, waited a second, fuel then flowed out of line. I think this showed two things, one that the fuel filter was not plugged, two that the tank held pressure, but I don't know if this tells me anything or not. Any other tests I should do?

Fuel delivery:

I don't know if the impulse line is working properly or not, but I'm not sure exactly how to check that. I think that works off of crankcase vacuum to suck fuel into the carb diaphragm, is that correct? If I'm seeing fuel on the plug can that problem be ruled out?


Manually priming fuel:

I would like to do this, but I'm not sure how much fuel to squirt into the cylinder. Too much would probably flood the plug, too little may not ignite. How do you know if you've put the right amount in?


Pulling muffler:

I know this is easy, but I have one question. What's the chance that 8-year old bolts will just snap off in the cylinder when I try to remove them? I really don't suspect compression since the saw ran fine last time, and I have no reason to believe the piston/cylinder was damaged during the last usage. I don't want to create a new problem for no reason, so I've avoided this step for the time being. If this is zero-risk, and I can reuse the old gasket, then I guess I have nothing to lose. If I need a new gasket then I have to go pick one up. I also have to go buy a long allen wrench socket since the one I have isn't long enough to reach the bolt heads.

New plug:

I'm going to do this because its so simple, but in 35 years of experience with cars and motorcycles I've never seen a bad plug yet, but I guess there's always a first time.


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## scottr

Have you ever had a air cooled engine with a spark plug that would not fire ?


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## cityboy

scottr said:


> Have you ever had a air cooled engine with a spark plug that would not fire ?


 
No, but I haven't owned much in the way of *** until the last few years, maybe they're different. 

Prior to that the last air cooled engine would have been a late-'80s Yamaha motorcycle. Rode all my motorcycles regularly, year-round, and maintained them properly so I never had to troubleshoot them much.


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## From009to090

If the flywheel key was snapped and timing was off, you would still get some backfiring, sometimes thru the carb. No POPs at all, check plug, plug wire, etc...  while the plug is off, squirt about 1/2 teaspoon of fuel mix in there and see if that makes the saw POP a couple times. Do you have an in-line spark plug tester, so you can test the spark without pulling the plug?


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## cityboy

From009to090 said:


> If the flywheel key was snapped and timing was off, you would still get some backfiring, sometimes thru the carb. No POPs at all, check plug, plug wire, etc... while the plug is off, squirt about 1/2 teaspoon of fuel mix in there and see if that makes the saw POP a couple times. Do you have an in-line spark plug tester, so you can test the spark without pulling the plug?



Unfortunately I don't have anything in the way of test equipment for engine diagnostics. I have the inclination to fix this thing myself, but don't feel like spending much money on stuff that I'm not going to use more than once every few years, if that often. I finally found a local guy that has a good reputation for fixing small engines, and he told me for $20 he'd diagnose the problem and then its up to me to decide if I want to fix it myself or have him do it. I can't even buy a compression gauge for that price, so if a plug swap and fresh fuel doesn't fix the problem its going in to him on Monday AM.

I'm also going to look at the flywheel key just to rule that out, but I can't imagine how that could have sheared off without subjecting the saw to some very abusive treatment. 

I may still have a weak coil, so I'm going to try one of those cheap in-line testers from Harbor Freight, but I'm not sure how good those will work for $4. If that doesn't detect any problems I'll just let him figure it out on Monday.


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## Fish

Sounds like you need to read post #2.....


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## mweba

Fish said:


> Sounds like you need to read post #2.....


 
Made me look lol.


What color is the spark?

Have you spread the gap to check spark?


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## homelitejim

You do not need all the tools. checking spark is easy, first pull the plug from the cylinder then plug the spark plug back into the wire lean the base of the spark plug against the cylinder or one of the fins so u can see the diode, pull the cord and look for bright blue spark and listen for crackle. If this is impossible then grab the spark plug with bare hand and pull the cord, no crying because it only hurts for a second and u saved some money. If the spark is yellow or orange or u did not pee yourself then it is not getting enough spark and your problem will lie in the electrical side of the saw. on the gas side open up your needles about 2 turns pull choke and set throttle lock, if after a few pulls gas is not visibly leaking out of the muffler you have a fuel flow problem, start from the tank and work your way to the carb. This is not rocket science just seems that way until u get your hands dirty a few times.


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## Slamm

If you have a lighter handly for a flooded cylinder, just take the plug out and light the cylinder ........... dries out real fast. Had my nephew running the 361 and at first he couldn't get the hang of pulling the cord fast enough to spin it and start, anyways, he flooded about 3 saws in short order. I happened to have BBQ grill lighter, or one of those long skinny ones, handy, and I just stuck it through the enlarged side port from modding the muffler and light the gas inside the cylinder, it didn't really do anything exciting except burn for a few seconds. I fired them up right after that without any problems.
Oh, and reset your L and H screws to 3/4 out or whatever settings is correct for your saw. If you just got the saw or something and not sure they were set correctly before, this causes issues, as well as, the aforementioned advice.
Sam


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## ncfarmboy

russhd1997 said:


> Remove the muffler and look at the piston. I had the same thing happen to one of my saws. It felt like it had compression with the plug in it but it didn't have enough. The exhaust side of the piston was scored.


 
I too had that happen to me on a Jred 670 Champ. Saw would hang by cord, pulled over like it had comp. Changed coil, plug, rebuilt carb., pulled hair, talked ugly, pulled muff no visible score on piston. Finally did comp. check 75 lb. Pulled cyl. was scored aroud the corner where I could'nt see it through the ex. port. 
Shep


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## a. palmer jr.

You really don't have to use a plastic gap gauge between the coil and flywheel. I loosen the screws on the coil to a little less than snug, insert the steel gap gauge and let the magnetism pull the coil into the gauge and flywheel, tighten up the screws and pull out the gauge.


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## homelitejim

my most valuable tool for setting gap is a business card, I get these free all the time. All you really need is a screwdriver, pliers, a few wrenches, and a good hammer, which can be bought for cheap at a pawn shop, second hand store, or even a yard sale.


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## LoggingEngineer

Fixed a 044 that had fuel spark and comp the other day that never would 'pop'. The flywheel key had sheared, timing was off, pulled the nut and could see the key, looked fine, but puled the flywheel and saw it was sheared, put in a new key, broke that one when it fired. Had to put in another key and a different flywheel since the other was wallowed out, trying to be cheap with a marginal flywheel sot me another key and a few minutes time. The brother in law was happy when I got it goin with used parts for him though.


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## a. palmer jr.

I had a Poulan 25DA once that had compression, spark and gas and wouldn't run. Turned out to be a busted crankcase that I didn't see until I'd done everything else to it.


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## cityboy

homelitejim said:


> You do not need all the tools. checking spark is easy, first pull the plug from the cylinder then plug the spark plug back into the wire lean the base of the spark plug against the cylinder or one of the fins so u can see the diode, pull the cord and look for bright blue spark and listen for crackle. If this is impossible then grab the spark plug with bare hand and pull the cord, no crying because it only hurts for a second and u saved some money. If the spark is yellow or orange or u did not pee yourself then it is not getting enough spark and your problem will lie in the electrical side of the saw. on the gas side open up your needles about 2 turns pull choke and set throttle lock, if after a few pulls gas is not visibly leaking out of the muffler you have a fuel flow problem, start from the tank and work your way to the carb. This is not rocket science just seems that way until u get your hands dirty a few times.



I guess I didn't mention all that I've tried so far, because I've covered some of them in previous threads. I've covered the basics like you mention. 

Have spark at the plug resting on the cylinder, but don't know if I have a strong enough spark. Hard to say exactly what color it is, its kinda yellow, orange, blue, depending on the lighting at the time I test it. Don't have a spare coil handy to rule out that option, or anything to measure how strong the spark is, so can't really say if its good or not. It didn't look weak to me, but I don't have enough experience to tell by appearance.

Have fuel getting into the cylinder, but can't tell if its too much, too little or just enough. The plug gets wet after pulling several times, and the choke lever is working normally. Also, since saw was running normally last time, I have no reason to start tweaking the H/L screws, they should be at the correct settings already. I've rebuilt small carbs before, so I would consider doing that, but not sure it would make any difference, I'd expect it to at least start but maybe run or idle lousy if the diaphragms were getting old.

Have compression, which gives a nice pop when I put my finger on the hole and pull, but again this is not very conclusive. Saw ran normally two weeks prior to this problem, so I have no reason to believe my compression went from normal to crap when the saw was running normally. Don't have compression gauge, so can't conclude anything here either. 

I pulled the flywheel bolt, expecting to be able to see the woodruff key underneath, but there's nothing to see that I can tell. I rotated the flywheel with an artist paintbrush handle in the spark plug hole on top of the piston and the timing appears to have the magnet and coil aligned at or just prior to TDC, so that seems like it isn't totally out of whack, but again, I can't tell if its exactly right without having a flywheel puller to remove and replace so I can see the keyway.

Oh yeah, I replaced the plug and that didn't help either.

So at this point I've tried all the simple things with no luck, and have no experience with troubleshooting saws, so I'm taking it to someone who knows what to look for and can diagnose the problem faster than I can. My time is worth more to me than the few bucks I'm going to be charged to have it diagnosed by someone who knows what to look for and has the ability to conclusively test various systems (or has spare parts to swap out).


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## macj

*don't dispair*

Citiboy, recently I was in the same space you're in.
Compression OK, fuel OK, spark appeared OK. 
However I did read here(somewhwere) that while you can have a spark when the plug is rested on the cylinder, it maybe insufficient to fire the mixture in the cylinder. 
Bearing in mind there seems to be no easy way of testing coils, I did a swap from another saw, and hey presto away she went!
Also there is a thread or two here that will tell you which Husqy saws have interchangeable coils.


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## angelo c

Like a good realtor would say...

Pressure

pressure

pressure(i.e. location)

test it....check for leaks. Pressure and vac test the case, hoses, lines tank .

I'm not understanding the refusal to purchase minimal tools for a guy who said he is now interested in owning ***. Most *** can and will need attention. Spread out the purchases of said tools but buy the darn things. Once you learn how to fix these machines they just show up at your garage door. Trust me it happens. Broken machines always find good mechanics...eventually.

A


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## Fish

Like I said, you need to read post #2, and of course follow it........

But now you have a loose flywheel nut you need to retighten so you won't shear the key when it finally hits and runs. You should do the rope method there.

But DRAIN the fuel tank, remove the plug, get a new one too, pull the rope a bunch with the plug removed, let it sit an hour or two, then put in the new plug and pull the rope a dozen or two times more with the trigger squeezed.

Then, when you are sure all of the old fuel is gone, get some FRESH gas mix, and pour a dribble, or use carb spray, and put a squirt in the Carb throat {air filter removed}, and pull some more with the trigger squoze and it should fire then die, then you know that it was either flooded or the gas in it was so old it wouldn't burn.


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## Fish

Please try that like I said, and tell us what you found.


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## chainsawcircus

Just from me but I have seen spark plugs that fire great out in the open, but when under pressure ina cylinder they really dont get it done. It does happen, may not be your case but I have chased my tail for hours and then found this.


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## a. palmer jr.

macj said:


> Citiboy, recently I was in the same space you're in.
> Compression OK, fuel OK, spark appeared OK.
> However I did read here(somewhwere) that while you can have a spark when the plug is rested on the cylinder, it maybe insufficient to fire the mixture in the cylinder.
> Bearing in mind there seems to be no easy way of testing coils, I did a swap from another saw, and hey presto away she went!
> Also there is a thread or two here that will tell you which Husqy saws have interchangeable coils.


 
You can test coils with an ohmmeter or an oscilloscope...much harder to check modules in electronic ignitions. I usually just replace with a known good one.


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## cityboy

macj said:


> Citiboy, recently I was in the same space you're in.
> Compression OK, fuel OK, spark appeared OK.
> However I did read here(somewhwere) that while you can have a spark when the plug is rested on the cylinder, it maybe insufficient to fire the mixture in the cylinder.
> Bearing in mind there seems to be no easy way of testing coils, I did a swap from another saw, and hey presto away she went!
> Also there is a thread or two here that will tell you which Husqy saws have interchangeable coils.


 
Yes, I am fully aware of the fact that you can have spark at ambient pressure, but it might not be strong enough at cylinder pressure. I even mentioned it in several of my posts. Since I only have one saw, and don't know anyone else with a Husky that will let me swap coils, I don't have that option available to me, otherwise I'd have already tried it.


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## cityboy

Fish said:


> Like I said, you need to read post #2, and of course follow it........
> 
> But now you have a loose flywheel nut you need to retighten so you won't shear the key when it finally hits and runs. You should do the rope method there.
> 
> But DRAIN the fuel tank, remove the plug, get a new one too, pull the rope a bunch with the plug removed, let it sit an hour or two, then put in the new plug and pull the rope a dozen or two times more with the trigger squeezed.
> 
> Then, when you are sure all of the old fuel is gone, get some FRESH gas mix, and pour a dribble, or use carb spray, and put a squirt in the Carb throat {air filter removed}, and pull some more with the trigger squoze and it should fire then die, then you know that it was either flooded or the gas in it was so old it wouldn't burn.



My flywheel nut is no longer loose, I tightened it (with a torque wrench BTW).

I drained the tank, removed the plug, got a new one too. Let it sit for hours, days, etc. All the old fuel was gone. Put fresh fuel in, no difference.


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## cityboy

angelo c said:


> Like a good realtor would say...
> 
> Pressure
> 
> pressure
> 
> pressure(i.e. location)
> 
> test it....check for leaks. Pressure and vac test the case, hoses, lines tank .
> 
> I'm not understanding the refusal to purchase minimal tools for a guy who said he is now interested in owning ***. Most *** can and will need attention. Spread out the purchases of said tools but buy the darn things. Once you learn how to fix these machines they just show up at your garage door. Trust me it happens. Broken machines always find good mechanics...eventually.
> 
> A


 

Simple economics. I can pay a guy $20 to diagnose the saw for me, or spend $40 on a compression gauge to make sure my compression is good, another $60 on a new coil (just in case the old one is bad), another $50 or so on pressure and vac testers, $20 or so on a flywheel puller to verify my timing is OK, and then MAYBE figure out why it doesn't run after spending $150-200 on special tools and parts swapping. I'm not planning on fixing a different saw every month for the rest of my life. Maybe where you live they just show up at your garage door, where I live you can't even find them if you actively look. I still have a bunch of special tools that I bought over the last 35 yrs. ago for a one-time motorcycle or auto repair that haven't been picked up since I used them for that first job. The difference there was the cost of the tools was minimal, and the cost savings by doing it myself were many times the cost of the tools. And, I knew how to finish the job once the tools were purchased. In this case its the opposite, the cost of the tools is several times the cost of having someone else do the work for me, and I don't actually know exactly what's wrong with the saw. If I did, I'd buy the one tool I actually needed and finish the job myself.


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## homelitejim

the 357xp is a nice saw and more economical to repair than replace. Why did you replace the decomp valve, did it not function or was it stuck partially open? Was this the only problem with the saw that you know of? I re read your initial post and for the life of me can't figure out why it won't run if all you did was replace the decompression valve. If you have compression, spark, and fuel but no fire I would say flip the switch to the on position, but since you have tested for spark and got some that would rule that out. The next best thing is to start ruling out things, start by rebuilding the carb, carb kits are usually under $20, replace your fuel line and filter usually under $20, replace the coil, not sure how much they cost but I bet it is cheaper than a new 357xp. Pull the muffler, check not only the exhaust side of the piston but also the back and sides of the cylinder, any lines up and down that are unmistakeably visible are a sign of trouble. When pulling the flywheel leave the nut on the crank but flush with the crank and tap with a hammer, you can use a flat screw driver as a pry bar on the back with a little pressure usually pops them right off, if this saw is that old usually saws made after the late 70's have electronic ignitions which means everything is in the coil. If that does not work then maybe it is time for expert opinion, if it does work then sell the thing and get a Stihl.


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## angelo c

cityboy said:


> Simple economics. I can pay a guy $20 to diagnose the saw for me, or spend $40 on a compression gauge to make sure my compression is good, another $60 on a new coil (just in case the old one is bad), another $50 or so on pressure and vac testers, $20 or so on a flywheel puller to verify my timing is OK, and then MAYBE figure out why it doesn't run after spending $150-200 on special tools and parts swapping. I'm not planning on fixing a different saw every month for the rest of my life. Maybe where you live they just show up at your garage door, where I live you can't even find them if you actively look. I still have a bunch of special tools that I bought over the last 35 yrs. ago for a one-time motorcycle or auto repair that haven't been picked up since I used them for that first job. The difference there was the cost of the tools was minimal, and the cost savings by doing it myself were many times the cost of the tools. And, I knew how to finish the job once the tools were purchased. In this case its the opposite, the cost of the tools is several times the cost of having someone else do the work for me, and I don't actually know exactly what's wrong with the saw. If I did, I'd buy the one tool I actually needed and finish the job myself.


 
Ok then, pay the man his $20 and lets see what he says is the problem. 
What's a guy like Fish and the rest of us yahoos know anyway. Besides, most of the tooling Im talking about can be "rented" from your Autozone for the grand sum of $0 dollars if you return them. I'ld like to visit this country called California some day. I hear its a hoot. Best of luck, or as the Southern contingent would say..."bless your heart".


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## cityboy

angelo c said:


> Ok then, pay the man his $20 and lets see what he says is the problem.
> What's a guy like Fish and the rest of us yahoos know anyway. Besides, most of the tooling Im talking about can be "rented" from your Autozone for the grand sum of $0 dollars if you return them. I'ld like to visit this country called California some day. I hear its a hoot. Best of luck, or as the Southern contingent would say..."bless your heart".



First of all, I have never disagreed with or disrespected any of the advice I've received here, so the 'yahoo' comment makes no sense to me, and suggests I am not taking the advice here seriously, which is completely untrue. I appreciate all the help suggested so far, so please don't suggest that I'm ignoring what's being said to me. 

Where I live, nobody gives you anything for free, or at least I haven't found any evidence of it yet, so the Autozone approach probably wouldn't work either. But thanks for the idea, I think I'll call them anyway.


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## avason

I would pull the kill switch to see if it fires up. Someone mentioned it before it happened on my 353. pretty easy to do. I pulled the contacts and put electrical tape around the terminal so it wouldn't ground out. if you did this already i must of overlooked it. Good luck.


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## Fish

If you have done as I have said, then take off the muffler and look at the scored up piston, as that is all that is left, probably burnt up by the
decompression button leaking, a scored up piston can mimic compression.
I always suggest the simple and cheap things to check first, as I hate wasting time and money, mine and other's.


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## cityboy

Fish said:


> If you have done as I have said, then take off the muffler and look at the scored up piston, as that is all that is left, probably burnt up by the
> decompression button leaking, a scored up piston can mimic compression.
> I always suggest the simple and cheap things to check first, as I hate wasting time and money, mine and other's.



Here are a few pics of the piston. One to show the ring, another the skirt, and the third is a closeup of the skirt to show some extremely fine scratches.

From a distance the piston surface looks good to me, but I have no idea how perfect it has to be for optimum compression. The scratches are barely visible, but are there, so I suspect them to be primarily cosmetic, no? The closeup shows they are maybe not quite as deep as the machining lines on the piston. 

when I pulled the muffler it had more gas in it than the fuel tank. At some point would that keep the saw from starting? I'm drying it out now, and will try again after its dried out.

I've been suspecting a marginal coil all along, and so far I'm not seeing any indication of fuel delivery or compression problems, so the coil/timing are still the chief suspects. I'm going to call the guy on Monday and see if he has either a) a spare coil to swap out, or b) a conclusive way to test my coil. If not, I think I'll gamble the $60 on a new coil from Bailey's and see what happens. None of the repair shops around here I've talked to even have a coil in stock, its a non-returnable special order.

Regarding muffler re-attachment, is it a good idea to put a dab of anti-seize on the bolts?

View attachment 199481
View attachment 199482
View attachment 199483


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## Fish

Well, a saw with a good piston, compression, and no fuel, will roar to life when primed for a second or two, so the ignition is where I would explore.

If you are sure the fuel is good, and the saw isn't flooded, etc.


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## Fish

Scratch my last post, I didn't read the text of the post, just looked at the pics.

Your saw is flooded.


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## Justsaws

cityboy said:


> Here are a few pics of the piston. One to show the ring, another the skirt, and the third is a closeup of the skirt to show some extremely fine scratches.
> 
> From a distance the piston surface looks good to me, but I have no idea how perfect it has to be for optimum compression. The scratches are barely visible, but are there, so I suspect them to be primarily cosmetic, no? The closeup shows they are maybe not quite as deep as the machining lines on the piston.
> 
> when I pulled the muffler it had more gas in it than the fuel tank. At some point would that keep the saw from starting? I'm drying it out now, and will try again after its dried out.
> 
> I've been suspecting a marginal coil all along, and so far I'm not seeing any indication of fuel delivery or compression problems, so the coil/timing are still the chief suspects. I'm going to call the guy on Monday and see if he has either a) a spare coil to swap out, or b) a conclusive way to test my coil. If not, I think I'll gamble the $60 on a new coil from Bailey's and see what happens. None of the repair shops around here I've talked to even have a coil in stock, its a non-returnable special order.
> 
> Regarding muffler re-attachment, is it a good idea to put a dab of anti-seize on the bolts?
> 
> View attachment 199481
> View attachment 199482
> View attachment 199483


 
Better dry out the crankcase as well, position it so that fuel can drain out the spark plug hole or exhaust port. Sounds like a stuck decomp and a lot of pulling completely flooded the saw.


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## cityboy

Justsaws said:


> Better dry out the crankcase as well, position it so that fuel can drain out the spark plug hole or exhaust port. Sounds like a stuck decomp and a lot of pulling completely flooded the saw.


 
OK, doing that now, seeing fuel dribble out of hole.

I don't know about the decomp valve itself, but the hose that connects it to the crankcase was cracked. When I tried to pull it off it just sheared and broke in half, so I'd guess it was probably pretty well cracked, but didn't look at it prior to pulling it off. Now have the decomp valve replaced with the cylinder plug, and have rigged a temporary hose blockage on the crankcase attachment end, so I think the cylinder is now sealed properly.

What I'm hoping may have happened is this: Decomp was leaking through crack in hose, valve itself, or both. I did notice that the pull resistance was starting to get a little weaker than usual, but don't run the saw often enough to be sure I wasn't just imagining it. In the process of trying to start it with low compression from the leak I flooded it. Then after fixing the compression leak, it was already flooded, so it still wouldn't start. If I fix the flooding problem, it may just start now. I'll keep my fingers crossed.


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## lfnh

cityboy -
if you have the time, can you snap a couple of good pics of 
1.carb side view including where it bolts up to the cylinder.
2.decompression valve (now a plug) and hose you mention.
3. Also can you post info from or pic of engine tag ?
Thanks


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## cityboy

lfnh said:


> cityboy -
> if you have the time, can you snap a couple of good pics of
> 1.carb side view including where it bolts up to the cylinder.
> 2.decompression valve (now a plug) and hose you mention.
> 3. Also can you post info from or pic of engine tag ?
> Thanks


 
Here's the carb top/left/right pictures. I know its dirty, didn't bother blowing it off with compressed air but I probably should. The arrows on the top photo are something that I'm wondering about. What is that open nipple for? There's also a slot in the plastic where a second hose could be routed, perhaps to that nipple. I'm pretty sure there's never been a hose there, or I would have seen the loose dangling hose at some point.

The decomp pic is also there, the rigged plug is a piece of fuel line that's very snug on the nipple coming out of the crankcase, and that's a nail plugging the other end of the hose, also very snug.

by engine tag do you mean the serial number plate? If so the info on that is only partially visible in one of the pics, here's the complete info:

965 55 04-00
03 4300476 (I think this means 2003, week 43, serial number 476)

I also finally did a compression test (thanks to the guy who suggested borrowing tools from AutoZone) and it only went to 125psi. The ambient temp was about 85F, so it might do a little better in the morning with cooler, denser air. I think that's a bit on the low end, but should be sufficient to run, shouldn't it??

View attachment 199514

View attachment 199515

View attachment 199516

View attachment 199517


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## lfnh

allowing for all, 125 psi is good enough to start (at least pop distinctly).
thank you for the pics.
keep the camera handy !


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## angelo c

cityboy said:


> OK, doing that now, seeing fuel dribble out of hole.
> 
> I don't know about the decomp valve itself, but the hose that connects it to the crankcase was cracked. When I tried to pull it off it just sheared and broke in half, so I'd guess it was probably pretty well cracked, but didn't look at it prior to pulling it off. Now have the decomp valve replaced with the cylinder plug, and have rigged a temporary hose blockage on the crankcase attachment end, so I think the cylinder is now sealed properly.
> 
> What I'm hoping may have happened is this: Decomp was leaking through crack in hose, valve itself, or both. I did notice that the pull resistance was starting to get a little weaker than usual, but don't run the saw often enough to be sure I wasn't just imagining it. In the process of trying to start it with low compression from the leak I flooded it. Then after fixing the compression leak, it was already flooded, so it still wouldn't start. If I fix the flooding problem, it may just start now. I'll keep my fingers crossed.


 
Cityboy, 
glad to hear the Autozone tip worked out for ya. Im a little concerned about that low of a compression. It should pop but it also is low. 135-155 is a normal ring wear range. I understand you don't have any others to confirm compression guage operation with. Im also surprised to see the shape of your piston knowing you are showing 125psi. I suspected some exhaust scuffing but see none in your pics. 

I understand you have a IPL for the saw and not a service manual ??? Im not understanding where you say that the "line connecting the decomp" was cracked. Im thinking you meant the impulse line and if you blocked that off you found a problem if not THE problem. Does that hose you describe connect the carb to the crankcase? If it does it needs to be replaced. Im thinking I am not understanding what you are describing. Maybe some more pics ? definately one of the impulse hose. 

stay with us we'll get you through this.


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## lfnh

I am no expert with this model Husky.
There are references to replacing the tie strap on the card boot/or the whole boot with Zama carb. Others will know for sure.
I think you're in good hands cityboy.

If these links help:
Workshop Manual

Photos borrowed from J. Walker thread

Pic1
Pic2


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## cityboy

angelo c said:


> Cityboy,
> glad to hear the Autozone tip worked out for ya. Im a little concerned about that low of a compression. It should pop but it also is low. 135-155 is a normal ring wear range. I understand you don't have any others to confirm compression guage operation with. Im also surprised to see the shape of your piston knowing you are showing 125psi. I suspected some exhaust scuffing but see none in your pics.
> 
> I understand you have a IPL for the saw and not a service manual ??? Im not understanding where you say that the "line connecting the decomp" was cracked. Im thinking you meant the impulse line and if you blocked that off you found a problem if not THE problem. Does that hose you describe connect the carb to the crankcase? If it does it needs to be replaced. Im thinking I am not understanding what you are describing. Maybe some more pics ? definately one of the impulse hose.
> 
> stay with us we'll get you through this.



Yeah, considering the shape of the piston I was expecting a better number also. I used a small bungee to hold the throttle open, made sure the choke was off, so I'm pretty sure I was getting good cylinder filling.

I do have the service manual that's commonly available online.

This saw has the auto-decomp feature, which involves a valve coming off the side of the cylinder (where the hex bolt head is now in the picture). That valve has a banjo-fitting on the end with a hose that attaches to a nipple coming out of the crankcase on the other end. The hose was cracked, or at least it came off in two pieces when I tried to extract it from the nipple on the crankcase.

The impulse line isn't loose as far as I can tell, but haven't done much but tug on it with a screwdriver to make sure it resisted that. Also, I'm getting fuel like crazy, so it would appear to be doing its job.

At this point I'm kinda ruling out the ignition timing being off because if anything happened like a twisted crank, or flywheel slipped on crank, the saw would have probably died right then, but the last time I used it nothing unusual happened and I shut it off normally. I could go back to AutoZone and get the flywheel puller, but I really don't suspect that for now.

What seems like the most likely cause now is a weak spark, that's something that I can't rule for sure.

If I'm getting so much fuel that the saw is flooding, I'm guessing that I would at least get it to start, but then maybe run bad, would you agree? If so, I'm going to rule out fuel problems for now too.

How about crankcase leaks through the crank seals? Would that prevent a saw from starting, or just make it run erratic once it started? I'm guessing that would also result in low fuel flow because it can't draw enough crankcase vacuum to pulse the impulse line.

Any and all answers would be much appreciated at this time because if everything else can be ruled out except for the weak coil, I might just gamble the $60 on a new one.


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## angelo c

City, 
autozone will "rent" you a mityvac pressure tester too. Might want to check that out for peace of mind. Are you getting any "pop" at all ? maybe dry it out again and just drop a eyedropper of fresh mix (new gas and new oil too 50:1) and see if it pops. Im wondering if the metering guage on the carb is bent or the diaphram is stiff. 

you do know this stuff is like a great murder mystery for us. We can't wait to find out "who dunnit" !!!!


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## Fish

Now I am getting pissed...... Dry the phacker out, hell mail the turd to me........ This is getting silly. I will fix the dam thing for free, you buy the part, pay the shipping.

But for sanity's sake, dry out the saw!!!!!


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## Fish

That is NEXT!!!!!


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## Fish

Or buy a mity vac, pressure tester, compression gauge, coil tester, multimeter, coil, flywheel, seals.........

Then dry out the saw and go through the carb!!!! And throw out that old fuel mix!!!!!!!


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## Fish

You have proven at least 4 times that you are not following any of the sane responses here, so go ahead and chase the rest....

Buy a full leakdown kit, a coil occiliscope, a voodoo witch's chicken carcasse, a new coil, carb, flywheel..... Go for it!!!!


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## rupedoggy

I am following this trying to make heads/tails out of it. The one glaring thing I see is "the hose going from the compression release(or decomp as he calls it) to the crankcase". There is no such thing in a saw that is functioning correctly. I think the blue end of the compression release popped off and somehow the IMPULSE LINE got snubbed off onto it. The op needs to identify the fuel line, impulse line and, if it has one, the tank vent line. No impulse line, no fuel pump!
Additionally the lines MUST feed to the correct place in the carburetor. Mike


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## Fish

No matter either way, but if the OP would dry out the saw completely, then the dry saw would fire up, then die, with a prime of good fuel.....

If not, then there is at least 1 other problem.............

No impulse lines, seals, leeches, whatever...

If the compression is good, which the pics indicate, the unit has spark, the flywheel key is good, but the muffler has fuel dribbling out, then that
is a clue.............


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## albert

Early 357's had a junk auto decomp set up. Very prone to failure, they did use a hose to the cylinder base which needs to be capped off and clamped with a proper cap and clamp. Hey City, you asked for help for a simple problem and got good advise. If you follow it, you will fix the saw.


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## rupedoggy

Thank you Albert. I'm on the sidelines again. Go get em Fish!


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## Fish

Naw, I am done with it....


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## cityboy

albert said:


> Early 357's had a junk auto decomp set up. Very prone to failure, they did use a hose to the cylinder base which needs to be capped off and clamped with a proper cap and clamp. Hey City, you asked for help for a simple problem and got good advise. If you follow it, you will fix the saw.


 
I'm not sure what advise you're referring to anymore. A lot of people have suggested things that I've already covered, they just didn't read the other posts that covered it (can't say I blame them, there's too many of them). Fish is all upset because he thinks I never dried out the flooding, but I covered that in post #44. All the other things I was asked, I did, and posted pictures as requested. There's a couple things I don't have the proper tools for, and I clearly stated that I couldn't do them. My last request was regarding if any of the things I can't do because of lack of tools can be crossed off the list based on other observations I've made. Seemed like a simple request to me, but nobody answered any of those questions, I just got a rant from Fish because he thinks my saw is still flooded. A couple days ago I said screw it, I'll take the saw to someone with the tools and experience to fix it, and everybody told me I should just do it myself and to not give up so quickly. So I can't win either way it would seem.

This thread has gotten too long, I've clearly worn out my welcome, so thanks to all for the advice up until now, but I'm done too.


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## Fish

Coming back to this.............


You need to "Dry Out The Saw" period!!!!!!!!!! First!!!! Cheap!!!!!! Free!!!!!!!!!!

You never did!!!!!!!!!!!

Drain the fuel, remove the plug, pull a few dozen times, let dry in the sun.............

When absolutely certain that the saw has been totally drained of all fuel, and all of the old stagnant fuel is LONG gone, no frign hint of any fuel
anywhere!!!!!

Put in a new plug, put a small squirt of fuel into the carb throat, with air filter/ bar-chain removed. Pull 20 times while holding the trigger all
of the way down, Of course with the damng ignition switch set to "ON"!!!!!!
If you still have not gotten it to "roar" momentarily, then you can rule out the fuel system!!!!!!!!!!

If it will hit and run momentarily, then you know what to do!!!!! Well maybe not!!!!!

If it won't hit and run a tad, then you have other problems, but since you have never even bothered to drfy out your turd, then you need to
stop wasting our time. We are not working on the space shuttle here!!!!


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## Fish

But all of this diddling around not doing anything anyone suggested pisses me off!!!!!


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## angelo c

Fish, 

maybe you should consider decaf for a day or two....:hmm3grin2orange: 

just kiddin ya !!!!

A


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## Fish

No, I just need to turn off the "puter" when I am "cookin" meth!!!!!!!!!!!!!!!!!!


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## Fish

I apologize, but a saw that will not even "hit", the problem area can be isolated in just a few minutes, this is not rocket science........

I did not say that the total problem could be layed out, but at least it could be isolated into one of the 3 areas quickly. But this thread has
been going in the other direction since post #1, because the O.P. won't do the proper steps.......


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## cityboy

Fish said:


> I apologize, but a saw that will not even "hit", the problem area can be isolated in just a few minutes, this is not rocket science........
> 
> I did not say that the total problem could be layed out, but at least it could be isolated into one of the 3 areas quickly. But this thread has
> been going in the other direction since post #1, because the O.P. won't do the proper steps.......


 

Fish,

First, I appreciate your trying to help me, so I'm not going to get into an argument over this, its not worth it. But I did dry out the saw, I'm not sure why you don't think I did. It didn't help. You asked me to pull the muffler so you could "see the scored piston" or something to that effect. I did that, and the piston was fine. I'm not sure what all you wanted me to do that I haven't done, you seem to be focused on screaming about the flooding never being addressed, but that's not true and I said so twice. But seriously, I agree with you 100% that this is too simple a problem to keep going on about it here, so I don't want to waste any more people's time with it. 

Now that the saw is dry, I'm going to put a little mix in the cylinder through the spark plug hole, or in the carb throat, and see if it will fire. That will also answer the question of whether or not I'm getting spark under compression. I'm sorry it took so long to get to this point, I'm totally new to this. If I knew enough about saw diagnostics when the thread started, I would have probably done this step first. But I'm a newbie so I don't know what I'm doing, I'm trying to learn. I thought I was trying everything I was told to try (except pull the flywheel), so I'm a bit surprised that you're saying I haven't co-operated since post #1, I don't think that's true.


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## a. palmer jr.

Put a small amount of fuel in the sparkplug hole. Replace plug. Turn on ignition. Give it a few pulls, it should fire if it has compression and spark at the proper time.

However, I have a 610 that appears to have lots of compression, has spark, I put a little fuel in it and couldn't get it to do anything. I guess it's something to look into this week.


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## rms61moparman

cityboy said:


> Fish,
> 
> First, I appreciate your trying to help me, so I'm not going to get into an argument over this, its not worth it. But I did dry out the saw, I'm not sure why you don't think I did. It didn't help. You asked me to pull the muffler so you could "see the scored piston" or something to that effect. I did that, and the piston was fine. I'm not sure what all you wanted me to do that I haven't done, you seem to be focused on screaming about the flooding never being addressed, but that's not true and I said so twice. But seriously, I agree with you 100% that this is too simple a problem to keep going on about it here, so I don't want to waste any more people's time with it.
> 
> Now that the saw is dry, I'm going to put a little mix in the cylinder through the spark plug hole, or in the carb throat, and see if it will fire. That will also answer the question of whether or not I'm getting spark under compression. I'm sorry it took so long to get to this point, I'm totally new to this. If I knew enough about saw diagnostics when the thread started, I would have probably done this step first. But I'm a newbie so I don't know what I'm doing, I'm trying to learn. I thought I was trying everything I was told to try (except pull the flywheel), so I'm a bit surprised that you're saying I haven't co-operated since post #1, I don't think that's true.


 



This happens here every now and then.
So many here were so anxious to help that you were trying to listen to them all at the same time.
Chainsaw diagnostics are really very simple but every mechanic, or hack in my case, has a different approach to it.
I like to start with the simplest (and usually cheapest) things first.
Others, depending on their level of experience and expertise with a certain model might try the "most likely" problem first.

Fish is probably one of the top ten best mechanics on this site and if you listen to him and do what he says exactly like he tells you to do it, you will know in short order what is wrong with your saw.
That is not to say that any of the other posters in this thread couldn't walk you through your diagnosis just as well, but the problem occurs when you try to follow too many of us at the same time.
Jumping from ignition, to compression, to fuel delivery then back to ignition and on to something else is the worst way in the world.
That is why I posted early and when I saw you had "too much" help, I beat feet to another thread.


Mike


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## cityboy

*its running !!*



rms61moparman said:


> This happens here every now and then.
> So many here were so anxious to help that you were trying to listen to them all at the same time.
> Chainsaw diagnostics are really very simple but every mechanic, or hack in my case, has a different approach to it.
> I like to start with the simplest (and usually cheapest) things first.
> Others, depending on their level of experience and expertise with a certain model might try the "most likely" problem first.
> 
> Fish is probably one of the top ten best mechanics on this site and if you listen to him and do what he says exactly like he tells you to do it, you will know in short order what is wrong with your saw.
> That is not to say that any of the other posters in this thread couldn't walk you through your diagnosis just as well, but the problem occurs when you try to follow too many of us at the same time.
> Jumping from ignition, to compression, to fuel delivery then back to ignition and on to something else is the worst way in the world.
> That is why I posted early and when I saw you had "too much" help, I beat feet to another thread.
> 
> 
> Mike



Saw is running, started a new thread about it because this one was beat to death, but wanted to close this one out too.

Thanks again everyone.


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## Fish

So this is the new thread????

http://www.arboristsite.com/chainsaw/181022.htm#post3188041

Fly it in under the radar, why don't ya???????


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## Fish

Let us all beat it to death some more!!!!


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## rms61moparman

Looks like it was flooded!!!
Whoda thunkit???


Mike


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## dom1971

Mine is a 391, it has spark, new fuel and high compression. It just came in the mail today with fuel in it so I drained the fuel and put in new fuel, pulled a bucnch of times and got one small sputter- thats all. Pulled the plug and saw there was fuel on the plug. whats my next move? BTW, the guy used old motor oil for bar oil so I got rid of that and rinsed with denatured alcohol


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## Strikert1

I am experiencing a similar problem with a O28. Coil tested good. (tried a new coil), Compression 145, New fuel filter and line, new air filter, New spark plug, carb rebuilt, fresh fuel, installed ignition chip to replace points. It has started and run for 3 to 5 min. After I shut it down I can not get it to start again. Help


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## Jason Richards

Question, I have a string trimmer that has solid compression, new carburetor, new spark plug and a cleaned spark arrestor screen...it still will not start. What the heck am I missing?

Fuel is getting to the chamber, spark plug has strong blue spark with proper gauge, compression is at 115, idk what else to look at... any help?

Bit of history, owner said it was working day he dropped it off to me for a tune-up just smoking a little and spitting fuel out of the exhaust. Cleaned everything up and first pull it sputtered and started with no power. Now it won't even sputter. I have another trimmer a troybilt TB22EC that is doing the same thing. New carb, new fuel, new spark plug good compression at 110.. neither of them will start.


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## rupedoggy

Since when is 115 and 110 GOOD compression????????????


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## Jason Richards

Since the manufacturer recommends between 110 and 120. Is that not good from your experience? I deal mostly with lawn mowers...


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## TBS

Does the troy bilt have an electric start? Those o-rings that seal the e start can shrink and crack.

What brand/model is the other trimmer.


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## Jason Richards

TheBrushSlasher said:


> Does the troy bilt have an electric start? Those o-rings that seal the e start can shrink and crack.
> 
> What brand/model is the other trimmer.



The other one is an ECHO SRM230. I have no idea what else to do to get these things firing up..


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## TBS

I would pull the spark plugs out and pull them over a bunch then let them sit upside down overnight to make sure any fuel is gone from the engine. When you get to them again throw a splash of mix fuel down the carb and try to start them.


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## James Lepper

Fish said:


> I apologize, but a saw that will not even "hit", the problem area can be isolated in just a few minutes, this is not rocket science........
> 
> I did not say that the total problem could be layed out, but at least it could be isolated into one of the 3 areas quickly. But this thread has
> been going in the other direction since post #1, because the O.P. won't do the proper steps.......


Hi Fish,
Just wanted to say thanks. My Poulan 2050 after 15 years service finally started running poorly. For 4 years this saw was used everyday to cut firewood. Burnt 3/4 tank each day. Then used weekends in winter only. As it was running poorly I rebuilt the carb and it needed the mixture a lot richer to run than original settings. 
So drained the fuel tank and gave it new fuel. Then it wouldn't start. Gave it a new plug first one in 15 years. New primer bulb as it seemed reluctant to prime. Wouldn't start. Put fuel in the carb throat, wouldn't start or fire even. Plug was wet. Read this thread. Saw your advice. Plug out, saw upside down and pulled starter loads of fuel poured out. Reset carb to original normal settings. Started it up adjusted carb a little to get a good cold and hot start. It runs like new again. 
The fault was probably the plug but rebuilding the carb did not hurt. Running it rich with the old plug then adding fuel manually flooded the poor little thing. Your advice saved me a lot of time and frustration.


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## Huskybill

I just went through this with a so called running hus 350 I purchased. I pulled the cylinder to change the plastic clamp to the clip clamp, carb manifold on cylinder, impulse line, gas hose, fuel filter, new base gasket. She fired right up after adding fresh gas. The saw is all orginal.

Btw, the plastic clamp, the boot was loose on the cylinder, impulse line was dry rotted, cracked, I replaced the fuel filter and hose figuring down the road it would bite me anyway.


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## rupedoggy

What would a thread be (started sept 2011) without HUSKYBILL telling us how he does it.


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