Some Advice About an 026 Please..

[cedarshark]

I recently purchased a used 026. It is in good cosmetic condition w/ new bar & chain but not running. A squirt of carb cleaner in the carb and it fired briefly on the second pull. Before going further, I decided to pull the muffler and check the piston. Looking through the exhaust port, there are light scuff marks on the piston on about half of the upper part of the piston. They don't look like "scores" but more like scuffs, but is there a difference ? Is a score defined as a scratch you can feel with your fingernail or a pick ?

Several years ago I re-ringed a Homelite SXL (with worse scuffing) that still runs fine but I don't know if a Stihl will tolerate this type of repair. I believe saw is worth salvaging, but $284 for an OEM cyl/piston set is pretty steep. Would you pull the cylinder and piston to see if the damage may be more extensive than the piece of the piston you can see through the exhaust port. Any help is sincerely appreciated.

 

[sloch24]

I recently purchased a used 026. It is in good cosmetic condition w/ new bar & chain but not running. A squirt of carb cleaner in the carb and it fired briefly on the second pull. Before going further, I decided to pull the muffler and check the piston. Looking through the exhaust port, there are light scuff marks on the piston on about half of the upper part of the piston. They don't look like "scores" but more like scuffs, but is there a difference ? Is a score defined as a scratch you can feel with your fingernail or a pick ?

Several years ago I re-ringed a Homelite SXL (with worse scuffing) that still runs fine but I don't know if a Stihl will tolerate this type of repair. I believe saw is worth salvaging, but $284 for an OEM cyl/piston set is pretty steep. Would you pull the cylinder and piston to see if the damage may be more extensive than the piece of the piston you can see through the exhaust port?Any help is sincerely appreciated.

Definitely.. It's not that hard to pull the cylinder on that saw... pull it, and see what you have. If it's not too bad, clean it up and put it back together. Chances are it's just scuffed. The cylinder will PROBABLY be okay, you might need a piston though. The cylinders clean up with some muratic acid and a q-tip.

Good luck!

 

[cedarshark]

Thanks...I believe that is wise advice before the saw is run any further. Would you suggest an OEM piston or aftermarket such as Meteor from Baileys ?? My plans are to use this saw as a personal saw.

 

[sefh3]

This is one of the easiest saws to rebuild. Pull the cylinder and take a straight edge and see if the scuffs are catchable. That will tell you if you hurt the cylinder. If they catch it's usually aluminum transfer if they don't than they are gouges.

 

[Jacob J.]

I'd go with a Meteor piston from Bailey's...

Don't run it on carb cleaner anymore- that stuff is death on the cylinder, piston, and main bearings.

 

[cedarshark]

I'd go with a Meteor piston from Bailey's...

Don't run it on carb cleaner anymore- that stuff is death on the cylinder, piston, and main bearings.

You are right, I know better but my spray bottle of pre-mix was nowhere to be found and the can of carb cleaner was handy. My bad..

If there is aluminum transfer on the cylinder and it can be cleaned with muratic acid...is it a safer bet to re-assemble with a new piston rather than re-ring the old piston ??

 

[sloch24]

You are right, I know better but my spray bottle of pre-mix was nowhere to be found and the can of carb cleaner was handy. My bad..

If there is aluminum transfer on the cylinder and it can be cleaned with muratic acid...is it a safer bet to re-assemble with a new piston rather than re-ring the old piston ??

It depends on how bad the piston is. If it's just a couple of little scuffs, you'll probably be fine. As long as the rings are good and free, you can try it and see how it runs. Now, if the piston is badly worn on one side or both, I wouldn't even bother with it, and pick up a new one.

 

[cedarshark]

It depends on how bad the piston is. If it's just a couple of little scuffs, you'll probably be fine. As long as the rings are good and free, you can try it and see how it runs. Now, if the piston is badly worn on one side or both, I wouldn't even bother with it, and pick up a new one.

Thanks for the help. I will pull the cylinder tomorrow and see if I can figure out how to post pics. I would like someone else(with more experience with scuffed pistons) to take a look. The little saw(026) is a joy to work on. Couple more questions:

1) Does the 026 respond favorably to porting ? Not sure I want to tackle this for a general duty firewood.brush clearing saw but would like to know if it has been done.

2) While in the Stihl shop this morning, I noticed the orange bottle of Stihl De-Greaser. Is this stuff worth $8 a bottle ?

 

[longbar]

Did you check compression? If the p/c isnt scratched I wouldnt worry about it unless the compression is low.

 

[blsnelling]

I wouldn't start it again until I had pulled it apart for inspection. All you're likely to do is further damage the cylinder. As cheap as a new piston is, I'd never reassemble with one that had scoring. An entire new OEM P&C topend kit can be bought from bcorradi for $85. I think pistons are like $35, if he still has some.

 

[isaaccarlson]

You can also pull the plug and look into the cylinder with a pen light.

works for me. Look at the piston from the exaust port and the cylinder from the plug hole. just my $.02

 

[blsnelling]

Is there a lot of carbon buildup in the exhaust port? You could have carbon scoring. If that's the case, you really ought to pull the cylinder just to scrape that out. You can decarbon the crown of the piston and the combustion chamber while you're at it.

You can have that cylinder off in five minutes, literally.

 

[RobertN]

i have an 024 mostly stripped. down; putting bearing, seal, and rings in it as soon as budget allows.

It was really easy to get access to the cylinder and remove it.

 

[cedarshark]

I wouldn't start it again until I had pulled it apart for inspection. All you're likely to do is further damage the cylinder. As cheap as a new piston is, I'd never reassemble with one that had scoring. An entire new OEM P&C topend kit can be bought from bcorradi for $85. I think pistons are like $35, if he still has some.

I pulled the p&c. The cylinder is salvagable and cleaned up with muriatic acid. Piston is toast. Am considering a meteor piston but would like an OEM if possible. How do you suggest I contact bcorradi ? BTW, thanks for the tip

 

[Bowtie]

I pulled the p&c. The cylinder is salvagable and cleaned up with muriatic acid. Piston is toast. Am considering a meteor piston but would like an OEM if possible. How do you suggest I contact bcorradi ? BTW, thanks for the tip

Last time I talked to Brad Corradi, he didnt have any pistons, but its worth sending him a pm. Be sure to specify whether its an 026 or MS 260, the pistons and cylinders are different.

Meteor makes good products as well, and are very reasonably priced.

 

[cedarshark]

Last time I talked to Brad Corradi, he didnt have any pistons, but its worth sending him a pm. Be sure to specify whether its an 026 or MS 260, the pistons and cylinders are different.

Meteor makes good products as well, and are very reasonably priced.

Pm'd Brad and he responded that he has no new ones but has an aftermarket piston and a used OEM w/new rings. I am sure we will work something out for one or the other. Thanks again for the help !!

 

[PogoInTheWoods]

Acid Cleaning Cylinders

The cylinders clean up with some muratic acid and a q-tip.

How so? I mean I get the acid eating the aluminum and all, but what's the way most folks do it? Is it better than emery cloth or fine grit paper? Seems like it
would be far superior and faster if done properly. Is there a rinse/polish process after the fact?

I have a cylinder that deserves a second chance if there's a way to breath a
few more pistons worth o' life through it before it's a complete goner.

Any tips on the acid etching approach will be greatly appreciated.

Poge

 

[MS260 Fan]

I don't think there's any magic to it. Dip the q-tip in the acid and apply directly to the metal transfer trying to minimize where the acid drips and runs. Be careful not to inhale too much of the fumes. A fan helps. Watch the acid bubble. When it slows down/stops, wipe with a rag and repeat. Every few times sand with 320 grit and go with a few more cycles of acid. Slow and steady will get you there. I use a razor blade to check to see if the remaining material is raised or scored.

BTW, I keep a small jar with baking soda/water mix to dump in there if I get acid where I don't want it. It also neutralizes the used up q-tips.

Best of luck!!

 

[JamesJems]

When you pull and inspect it, does it look like this: if so, it's fried. This is an MS260 cylinder and piston that I ruined. My own sordid saga from 2006 can be found here: http://www.arboristsite.com/showthread.php?t=40690

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