STihl 026 pro value

[md1486]

??, piston rings are always metal. In 2 strokes they are either iron or iron with a chrome plated face.

My bad. Like I said I have never rebuild a top end. The one that I have seen were grey/black and looked rubberish. Didnt know the were metal. Now I know. I watched donyboy on youtube rebuilding a ms260 top end, that give me an idea what im gonna have to deal with

 

[mogulmasher]

My bad. Like I said I have never rebuild a top end. The one that I have seen were grey/black and looked rubberish. Didnt know the were metal. Now I know. I watched donyboy on youtube rebuilding a ms260 top end, that give me an idea what im gonna have to deal with

No biggie we all have to start somewhere! Good for you for being willing to tackle this rebuild job and learn. I myself have really only begain wrenching on saws, they are real easy once you start getting into them. I'm not new to working on engines though, been rebuilding 2 stroke sled engines for 30 years now and have cranked together my fair share of small block Chevys.

 

[TheTone]

Be glad it's a Stihl pro saw. Top end rebuild is much easier than the homeowner clamshell types. Just unbolt the cylinder, slide it up and every thing is right there, ready to disassemble. I have an 034 and it punches above its weight class.

 

[md1486]

Im starting to slowly disassemble the saw. Remove the carb, collar and the metal ring. Is this normal that there is no nuts between the air filter and the carb ? The ones I have seen already had 2 nuts. And as I see, I assume there is no impulse line on those model? i.e. the impulse is directly connected to the carb ? Now I dont have hex key long enough to remove cylinder so cant go further for now.

 

[John Lyngdal]

I have an OEM 034 cylinder in really nice condition sitting in my parts box. That and a Meteor piston should have you back up and running.
Might even have a piston, but didn't spot it on my first search.

 

[md1486]

I have an OEM 034 cylinder in really nice condition sitting in my parts box. That and a Meteor piston should have you back up and running.
Might even have a piston, but didn't spot it on my first search.

Nice. Im about to remove the cylinder to see what he looks like. Gonna know if only piston needed or not. I will message you back for sure. But I just broke my hex key in the skew..really dont know how im gonna remove that

 

[md1486]

Finally got it. Here what my piston and cylinder look like. What do you think about that? Complete kit or only piston and rings ?
And my biggest concern is, how im gonna know what caused this piston to score ? I dont have any pressure gauge or something similar. Would not be cool to rebuild and burn it few months later.

 

[Duane(Pa)]

Im starting to slowly disassemble the saw. Remove the carb, collar and the metal ring. Is this normal that there is no nuts between the air filter and the carb ? The ones I have seen already had 2 nuts. And as I see, I assume there is no impulse line on those model? i.e. the impulse is directly connected to the carb ? Now I dont have hex key long enough to remove cylinder so cant go further for now.

You are correct. There should be nuts holding the carburetor on those two studs in top pic.

Impulse signal comes through the hole at 1 oclock position in second pic.

 

[Wood Doctor]

OP said, "And my biggest concern is, how am I gonna know what caused this piston to score?"
-------------------------------
Could be several possibilities -- bad fuel, poor fuel mixture from carb, overheating, air leak, etc.. Your bet bet is it to rebuild the top end as I said above and start over. I would take Chainsaw Jim's offer in a minute and let him do what he offered to do.

 

[NCPT]

If the carb did not have nuts to hold it on tight, then that could be why your piston and cylinder are scorched. Saws are pretty easy to work on but I would have cleaned everything real good before dissambly. Good luck on the rebuild.

 

[Wood Doctor]

If the carb did not have nuts to hold it on tight, then that could be why your piston and cylinder are scorched. Saws are pretty easy to work on but I would have cleaned everything real good before disassembly. Good luck on the rebuild.

I seriously doubt the saw (an 034, BTW) would ever have started and run without the carb nuts holding the carb in place, tightly against the intake manifold. Just MHO.

"... broke my hex key in the skew"? This saw's cylinder was bolted on with hex rather than #27 torx head screws? MD1846, please go no further and send this saw to Chainsaw Jim as he offered. Thanks, and I'm out of here.

 

[md1486]

I seriously doubt the saw (an 034, BTW) would ever have started and run without the carb nuts holding the carb in place, tightly against the intake manifold. Just MHO.

"... broke my hex key in the skew"? This saw's cylinder was bolted on with hex rather than #27 torx head screws? MD1846, please go no further and send this saw to Chainsaw Jim as he offered. Thanks, and I'm out of here.

I confirm 100% there was no nuts that hold that carb in place. Maybe the air filter hold it.

 

[Huntaholic]

DO yourself a favor and watch a LOT of youtube videos on how to replace the top end! Its not complicated at all but if You've never wrenched on a saw before it can be overwhelming at first. Those cylinder bolts should have been torx head, NOT hex or allen head. Its a shame you are so far away, Id be more than happy to swap it for you and let you watch the process to learn how. On the older model 034 the filter screws DO IN FACT hold the air filter to the carb.

 

[md1486]

DO yourself a favor and watch a LOT of youtube videos on how to replace the top end! Its not complicated at all but if You've never wrenched on a saw before it can be overwhelming at first. Those cylinder bolts should have been torx head, NOT hex or allen head. Its a shame you are so far away, Id be more than happy to swap it for you and let you watch the process to learn how. On the older model 034 the filter screws DO IN FACT hold the air filter to the carb.

I would be more than happy to learn from someone why experience. That would be the best for me. And It was in fact torx screw and not hex, I tell the wrong name but used the right tool (torx). My 034 is probably an older model then, since I have no nuts that hold my carb

 

[@ryan]

@md1486 How did the top end rebuild turn out?

 

[md1486]

@md1486 How did the top end rebuild turn out?

Its turned out well. I bought two AM P&C kit. Put one in with homemade ring compressor, took me about an hour. Ran about 3-4 fuel tanks 35:1 since then, run well.

 

[grizz55chev]

They’re made to run on 50:1, break in it’s ok to run 40:1.

 

[md1486]

They’re made to run on 50:1, break in it’s ok to run 40:1.

Yes I know but since this was my first P&C rebuilt I went on the cheap side AM kit. So ran it on 35:1 on the first few tanks and then im gonna run it on 45:1 like my other one.

 

[md1486]

Yes I know but since this was my first P&C rebuilt I went on the cheap side AM kit. So ran it on 35:1 on the first few tanks and then im gonna run it on 45:1 like my other one.

in fact im guessing on my fuel mix for this one. I have seen donyboy on youtube pouring a few drops of oil directly in the fuel tank for the first few one.

 

[lambs]

I'm no saw builder, but if I were you I'd refrain from guessing on the fuel mix. You've done a lot of good work, and it would be a shame to lose that investment .