Aftermarket Cylinder... good and bad... the Truth!

[watsonr]

Well I have one question that I need an answer for about an am 039 am p/c kit. I will be sending back my second kit from nws that has low compression 115 at best with two tanks of fuel through it. I gave them a second chance and not again. I need a cylinder that is nik bore and a decent piston. I was leaning towards one of the hyway's from watsonr. That looks like the only nik kit I can find, Anyone used a 039, any pics of it, it would be awful nice to get a cylinder that gives my at least 150psi to start with. I dont want to tear this thing down again.

How does it run?

 

[bushwackr]

Well it seems to run ok, im not impressed with power in the cut , it wont hold a steady idle unless I idle it lean. Its had more power with the bad p/c that was on it and it was a 46mm, I figured the 49mm would give me the little extra I was wanting from it. Im really bummed about this so called great idea I had:bang:

oh ya and the carb was retuned, I had to lean both low to idle and high to get it to run freespeed of 13,500, Thats where the 029 ran for as long as ive had it, all the saw has is muffler opened up. I sure thought I would have to richen it on the high for higher displacement.

 

[Michaelzz28]

Did you call them? I still ain't figured out why you guys keep buying kits that don't get some kind of warranty or from someone who doesn't stand behind their stuff??

The piston pin came out... sounds like a failure to me. I warranty against failure, piston pin, rings, cylinder plating, cir-clip, piston and cylinder. If you use due care in putting the saw back together and it fails, I replace the kit.

What kind of kit was it? And stay away from BB kits for that saw, buy the Tecomec kit for a 361 in 47mm, great kit!

I did call them they Issued me a rma and I am sending it back they said they would give me a refund we will see! that is the reason I asked if you warranty this sort of problem! I placed a order on your website this morning for a Tecomec Stihl MS361 Aftermarket Cylinder Kit 47MM CLass A Kit so I can get this thing running again need it as it is my favorite go to saw hopefully you are correct on the quality of the kits. I still have the oem cylinder and have cleaned it and believe I could reuse it with a new piston I tore this saw down for a cleaning and saw a little scouring on the exhaust side piston skirt so I went a new cylinder because of it but I believe I could just buy a piston and use the oem jug if these kit do not work out! please send me a good one THanks for the response

 

[watsonr]

Well it seems to run ok, im not impressed with power in the cut , it wont hold a steady idle unless I idle it lean. Its had more power with the bad p/c that was on it and it was a 46mm, I figured the 49mm would give me the little extra I was wanting from it. Im really bummed about this so called great idea I had:bang:

oh ya and the carb was retuned, I had to lean both low to idle and high to get it to run freespeed of 13,500, Thats where the 029 ran for as long as ive had it, all the saw has is muffler opened up. I sure thought I would have to richen it on the high for higher displacement.

Have you checked for a leak... impulse line, fuel line and seals? Is 13,500 the recommended RPM for that saw, well for a 390?

 

[watsonr]

I did call them they Issued me a rma and I am sending it back they said they would give me a refund we will see! that is the reason I asked if you warranty this sort of problem! I placed a order on your website this morning for a Tecomec Stihl MS361 Aftermarket Cylinder Kit 47MM CLass A Kit so I can get this thing running again need it as it is my favorite go to saw hopefully you are correct on the quality of the kits. I still have the oem cylinder and have cleaned it and believe I could reuse it with a new piston I tore this saw down for a cleaning and saw a little scouring on the exhaust side piston skirt so I went a new cylinder because of it but I believe I could just buy a piston and use the oem jug if these kit do not work out! please send me a good one THanks for the response

The Tecomec line is a good line. You won't have any problems with that cylinder.

 

[8433jeff]

Have you checked for a leak... impulse line, fuel line and seals? Is 13,500 the recommended RPM for that saw, well for a 390?

Sounds a little high. I'd drop it at least 10-15%.

Only lean it if it doesn't clear out in the wood.

 

[watsonr]

Sounds a little high. I'd drop it at least 10-15%.

Only lean it if it doesn't clear out in the wood.

Was thinking the same thing. 13,500 is pretty high, may be the number, I don't know for sure.

 

[Typhke]

Have you checked for a leak... impulse line, fuel line and seals? Is 13,500 the recommended RPM for that saw, well for a 390?

Based on the rpm list I've got, 13,000 is recommended for the 039/390.

 

[PogoInTheWoods]

Based on the rpm list I've got, 13,000 is recommended for the 039/390.

13,000 is "max permissible" for the 310 and 390 according to the shop manual . 12,500 is spec'd for the 290.

 

[PogoInTheWoods]

I did call them they Issued me a rma and I am sending it back they said they would give me a refund we will see!

I had no problem getting a refund from the vendor, though I didn't install the kit, let alone modify it prior to installing it. I'd be surprised if they issue a refund in your case, but ya never know...

I'm also surprised they are still selling that kit since they told me the one I bought was the last one on the shelf and it was highly unlikely they would be re-stocking due to the poor and inconsistent casting quality.

They were honest and forthright about the matter, but ya get what ya pay for...and that includes the vendors who sell such cut-rate merchandise...which is exactly what this particular kit was in my case.

 

[watsonr]

13,000 is "max permissible" for the 310 and 390 according to the shop manual . 12,500 is spec'd for the 290.

So were all saying the same thing... 13,500 is to lean for that saw and you will have problems, if I'm reading this correctly?

 

[PogoInTheWoods]

So were all saying the same thing... 13,500 is to lean for that saw and you will have problems, if I'm reading this correctly?

Stock, yes (imho).

 

[8433jeff]

Stock, yes (imho).

I would say until its broken it its too high stock or not.

 

[PogoInTheWoods]

I would say until its broken it its too high stock or not.

I meant "un-modded".

 

[bushwackr]

Yep no leaks, new seals, lines new from the first cylinder kit. I would still be running to 029 top if the intake boot didn't tear, that's what torched the other cylinder, it still ran but low compression also. I have been running that saw at that speed forever and never a issue, so I don't think the extra 500 rpm is the issue. I figured that if the muffler is opened up might as well gain a little. I sure though I wasn't pushing it, I always use good fuel and oil. Anyhoo. That should have nothing to do with the new cylinder having low compression. I had 120 never fired oily cylinder, to me that's not acceptable, but already I put it together and needed the saw so I ran a few tanks thru it now its 115 tops, not pleased. I contacted I will say the retailer. They acted like I was the only person to ever contact them about a problem like this, I told them I read on AS that im not the only one, all he said there's lots of bad info, and lies on here about his products. Well I will believe the folks here over one person that send me bad stuff. Im don't mean to sound cocky but, i did not build the engine wrong like the retailer tryed to tell me.

Forgot to mention the first 2 tanks of fuel thru it was 45:1, at a 12k top, I didn't run it that high the whole time, after the second tank I sure did

 

[bushwackr]

Btw pulled the muffler off the saw look thru the port the piston still looks like it just come out of the box. Not a mark or a scratch

 

[watsonr]

Some of the aftermarket kits do have lower compression and have for a while now. I think there just not that tight and for the most part, still allow a saw to run pretty good considering the saving you may have enjoyed. By replacing the cylinder and gaining that 30psi, how much performance are you expecting? A cut that's 1 second faster. being able to lift the rear handle till the rubber mounts scream?

Not trying to be an a smarty pants, well really, i am. I want to know what you expect so that I can get the same info to a manufacturer when he asks why? I've had kits that only made 120psi, saw started and ran well. Put the tester on it, 120psi and because of some of the hype around here of 180psi saws and such, felt like I got ripped off.

A little more research and some understanding of how it works, I've come to believe that it is a number sometimes used to consider engine help but is not the end all of engine health. Its a combination of the tune, the condition of the rings and piston, cylinder size, combustion chamber size and form, Squish, and ...... you get the idea.

You may find that most of the aftermarket kits do play it a little conservative for compression. I think its because they sell to a large market in different countries and whats important to us may not be to the the users of the world in general. Most may not care what the compression is as long as it runs and cuts, most are satisfied.. he may have not had anybody call back on lower compression, that answer has really a high probability of being true.

 

[bushwackr]

I understand that this saw isn't a race saw or nothing and was never intended to be anything but a throw away saw by what I get from everyones general bashing of them. Its just my opinion of them but I like running this thing as a matter of fact, my 036 and 026 have rested in the shop since I got this one. My way of thinking is if I start with a jug that has just as low of pressure as the bad one, how long will it be until im doing it again. Will. I get years out of it if I use bad parts. I was going to buy one of your hyway kits for it, but if im not going to get any better out of it than what it is now then what's the point. I might as well patch it up and unload it. That's why I was asking if anyone has used them and what are they getting. Since I can't find a good oem jug im kinda stuck

 

[bushwackr]

I understand that its just a number but it should get more life,and performance out of it with it higher, and its kinda hard to sell a saw when that's what most people look for when they buy a used saw, the overall condition and what ever the tester says.

But either way this kit is going back and I will prob be picking up one of hyway kit as soon as I get refinded for this one. If it ends up starting low at least the nikasil will hold up longer

 

[watsonr]

I honestly stopped looking at the number awhile ago. If it runs well, it runs well. Most of my saws are older saws and they are getting 110-145ish, guess I'm just used to a lower number.

Anybody out there with a Hyway kit in 390 size have a compression number we can see?

Nothing wrong with that saw, Pro saw or otherwise. Its a saw made to cut wood and warm families just like the other more expensive ones. I own cheaper saws for the same reason a'lot of folks do... because that's what i can afford, it's still made to cut wood!