Stihl 026 rebuild

[czar800]

I got this saw for free off a good friend.



So I started to look it over and found the piston was scored.

 

[czar800]

 

[czar800]

So I cleaned up the cylinder the best I could.looks like it's going to be usable

 

[czar800]

My plan for the saw is new piston rings all new rubber hoses give it a port job.
I've talked to a few members about the recipe that works well for the saw.
I'm stopping tonight at a friend of mine that's going to make me a mandrel to cut the squash and get the exhaust as low as I can. Thinking something like 102-104 Ex 117-118 T 75 IN. What do you "clowns" think.

 

[Canadian farm boy]

Did you do a pressure/vac test after you found the scored piston? Bearing ok?

 

[czar800]

Did you do a pressure/vac test after you found the scored piston? Bearing ok?

Yes, tested out just fine.

 

[Canadian farm boy]

Curious as to why it scored. Lean tune maybe? Not enough oil in the mix? I just hate to see someone rebuild a saw and then fry it again. Carry on. Looks good buddy

 

[czar800]

I'm not sure what happened, I believe the impulse line may have been leaking? When I got the saw I was looking it over and moving around the inpluse line just to see if it was toast. Then I tested it. When I got the saw apart and could see the barbed fitting it was pretty dirty like the line Had been part way off.

 

[huskihl]

Make sure it has a 3 screw carb, h l and idle. Many of these did not have an adjustable h jet.

 

[czar800]

Make sure it has a 3 screw carb, h l and idle. Many of these did not have an adjustable h jet.

Has a wt192 on it. Going to put a kit in it also.

 

[czar800]

Parts came in the mail today

 

[Gentleman]

I am wondering why the extra set of Caber rings? Meteor pistons come with Caber rings.

 

[drf256]

Has a wt192 on it. Going to put a kit in it also.

192 or 194?

 

[czar800]

Good observation, I have more than one 026 under the knife.

 

[czar800]

Sorry, not a 192 it's a 194.

 

[drf256]

 

[czar800]

Update: dropped off the piston/cylinder at a friends to get cut. He's also going to make me a the mandrel. He's a very skilled and runs a wire edm cutting machine? He's going to make different cutting angles for the squish band 0-5 degrees just so I have then! He worked under some nascar engine builder machining stuff. Needless to say I was there all morning!

Question, how far should I advance the timing?

 

[stihl_head1982]

subbed for the results

 

[drf256]

Update: dropped off the piston/cylinder at a friends to get cut. He's also going to make me a the mandrel. He's a very skilled and runs a wire edm cutting machine? He's going to make different cutting angles for the squish band 0-5 degrees just so I have then! He worked under some nascar engine builder machining stuff. Needless to say I was there all morning!

Question, how far should I advance the timing?

.025 of the keyway. Most recommend .020, but I've gone as much as .030 and got more rpm. I find .025 to be a good balance.

Mandrel angles sounds interesting. You're gonna cut the piston dome off, correct?

Is he making you angled sanding mandrels as well?

 

[drf256]

Depending on which jug you have, you will begin to Freeport the exhaust piston skirt somewhere around .055 from the band with a .020 squish. Just so you know.

I leave an approximate .006 of dome on the piston edge and hand sand the rest of it flat. If you're off and your freeporting alot, you can leave a bit of the radius to keep the piston taller. Not ideal to leave that small deadspace, but it works.

Just how I've been doing it, not necessarily correct, and others may do it better.