is this piston ok to run? 038 av super

[mcdarvy]

View attachment 311565View attachment 311566

038 AV super.

piston top and top brim are damaged, big groves!, but no damage below the rings. carb side piston looks nice, piston chamber is in great condition.

ok to run?

i flushed out chamber with gas and air many times,

can i run this saw for a few months and then rebuild?

or will running this saw result in further extensive damage?

i can not rebuild until winter, i need saw as back up for 2172 over firewood season...

should i take apart cylinder and full clean? can the piston be grind-ed down and touched up.
i plan on doing a piston rebuild is it ok to run with out any further cleaning? to avoid unnecessary work.

thank you for your time and responses they are much appreciated.

 

[blsnelling]

It's too easy to remove the cylinder and de-carbon everything, and not worth the risk of missing something critical. You've likely spent as much or more time flushing it than you would have just biting the bullet. It really is just that easy. We've got your back

 

[Nate66n1]

If your seeing scoring on any of the piston that means there's a problem. If it was my saw I would retire it whether you need it or not. Better to be safe then sorry

 

[brokenbudget]

let alone the crap that's been flushed down into the bottom end. time to pull the cylinder and do it right.

 

[mcdarvy]

let alone the crap that's been flushed down into the bottom end. time to pull the cylinder and do it right.

i shall do so,

thank you all for responses,

 

[Mad Professor]

I think pull the jug and de-carbon then throw in a set of caber rings.

Check your mix ratio and/or carb settings

 

[SEAM]

If the top and brim show damage (pitting), something must have bounced about in there, possibly pieces of one of the bearings.
Time to investigate in my opinion.

 

[mcdarvy]

i picked up a new piston kit for cheep at local saw shop, witch is cool but this chamber looks shott....

View attachment 311643

i gave the chamber a quick bath of snobol , is the chamber shot?, other side looks great..but a bunch of chrome missing?

i did not find the cause of damage, ---lower engine looks good , tight , smooth, i will re inspect it several times though, i may have flushed it out, though the damage looked old --as in soft wear over damaged areas-- the saw sounded smooth and has good compression as rings were great, iam glad i decided to look inside before running it...

i much appreciate the advice and info

 

[mcdarvy]

I think pull the jug and de-carbon then throw in a set of caber rings.

Check your mix ratio and/or carb settings

i bought the saw for 125, haven't used it yet, but when i dumped out the gas it was fresh, but the thickest oil ratio ive ever seen, like 15;1 or something, its a wonder it ran at all and iam not surprised the insides looked like my flue...

 

[MnSam]

If t where mine, I'd take some 400 grit paper lightly to the upper portion of the cylinder with your hand, clean it well, put in some new rings and run it. Looks like all the carbon damage is above the rings.

 

[mcdarvy]

View attachment 311728

looks shott, anyone have an extra 038 piston chamber?

the chrome is missing quite a bit, above exhaust port.

 

[blsnelling]

That cylinder is shot! You're missing a lot of plating above the exhaust port, where it counts the most. Don't even waste your time on it. It must be replaced. Sorry

 

[mcdarvy]

thanks brad, i thought so, ive learned a lot from your posts, my moded saws are all running great!

should i go with the 52mm kit on fleabay, ??

Nikasil Cylinder Piston Fits Stihl MS380 038 52mm Decompressn Gasket Bearing | eBay


i have an Italian 50mm 038 s piston kit new already though, only really need the 50mm piston chamber. the upgrade to 52mm looks worth it over buying just a chamber....? any thoughts anyone?