Who's running scored pistons in their saws?

[Four Paws]

This isn't a joke, but a serious question. When you have an old saw with an obsolete piston, do you turn the saw into a wall hanger, or do you clean up the piston, install new rings, and run it?

Obviously, this is largely based on the degree of scoring and whether or not the ring grooves are hammered.

 

[fearofpavement]

If the piston is unobtanium, what's it gonna hurt to run it?

 

[Big_Wood]

i've even taken some that were roached and very carefully got the rings out, clearanced the groove, cleaned piston up, and ran the the rings that were on the piston. none that i've sold though. i don't believe i have any that are running previously roached pistons currently. i think my 385 has a carbon smear on the exhaust side but that's about it.

 

[Rocketross57]

Been running a husqvarna 44 for a year now with a scored piston. Does fine. I always bring a back up though just in case!

 

[Big_Wood]

My grandfather has a 2100 he ran scored for 3-4 years. He ended up rebuilding it when the mains went. I'm not sure if it's still inning that same scored top end though. I should ask him. We just cut a bunch of alder yesterday with it.


Sent from my iPhone using Tapatalk

 

[jmssaws]

The strongest 372 I've had I carefully filed until I got the rings out then cleaned the piston up and it was bad, put it together with the same rings and over a year later it's the strongest of the few I got. All ported of course. I've used some bad ones

 

[Justsaws]

Use lots of saws with damaged pistons, do not to be obsolete. Lots of scored P/C are barely used.

 

[smokey7]

I have a few running with damaged pistons. Got one with a couple needle bearing fragment pits in the piston exhaust edge above the ring. I am running In the same cyl that it happened to. It also has some nice little marks between upper and lower transfer. also has plenty of
dents in the squish band. Still blowing almost 200psi cold. As far as a
totally scored seized piston with a mega smear stuck rings would only be a hanger toy for me. I am amazed
what will run way outside specs but
not a go to saw. My runners i try
hard to keep tight tolerance. Especially piston to cyl cclearanc. And ring gap. I can show you what i mean with pics if you want.

 

[jmssaws]

If I cut timber with it I would put a piston in it but a free saw a logger lean sized I'll usually put them together with what I got just to c what I got, if I can. I've got 3 372's two of them I bought as good running saws the other I got gave to me and the piston is pretty ruff but all 3 have 190 psi cold ,the scored one is the strongest. Not trying to say it will cut logs everyday for 2 years but a wood cutter would have a hard time wearing it out.

 

[wde_1978]

I will be re-using this one from my 1988. Sachs-Dolmar 105 , with a new ring as the original one wore quite thin:


After cleanup:


I somehow doubt I would find a new piston for this saw and the old one cleaned up OK.

The cylinder has two deeper score marks after clean up , but there is nothing I can do about that now - it will be re-used too.

 

[hotshot]

No problem for the unobtaniums, just look at this horrible gap toothed piston that had busted the top ring.
With new piston rings the saw still runs & cuts great.

 

[Deleted member 83629]

i do it all the time im about to clean this up to reuse.
not really scored but icky and has some light scuffing.

 

[Chainsaw Jim]

This ran just fine in my 372..

 

[GrassGuerilla]

Bought half a dozen Earthquake saws back in the deal. One was scored pretty good. Only had 135# out of the box. I sold four and kept two, one being the scored one. Both are still seeing regular use on the lawn care route. Both see a fair amount of use. Just checked, still 135#. It still remains to be seen if it will be the first of the six to become a parts donor.

 

[nitehawk55]

A lot of pistons get tossed that would work fine . If the scoring is not too extensive just clean them up (not too much material just smooth some) , clean the jug and of course correct what caused the seizing ! If the rings are marked at all they get tossed .

The funny thing is there is a lot of saws out there running fine that the owners don't even know have scored pistons !

 

[Rx7man]

My best running saw has the worst looking piston in it... deliberately. I did all my really iffy porting work on the worst jug I had.. jug is a bit scuffed, piston a little bit too, probably only slightly better than what Chainsaw Jim posted. I haven't HAD to run any worse ones.. the old Homelite 925 was absolutely demolished, so it was a no go..

This is a wall hanger (the homelite)



And how's this for "score marks".. that's what happens when 1 cylinder on a Cummins 5.9 runs very hot.. cylinder looked about the same too

 

[TreeTangler]

If I cut timber with it I would put a piston in it but a free saw a logger lean sized I'll usually put them together with what I got just to c what I got, if I can. I've got 3 372's two of them I bought as good running saws the other I got gave to me and the piston is pretty ruff but all 3 have 190 psi cold ,the scored one is the strongest. Not trying to say it will cut logs everyday for 2 years but a wood cutter would have a hard time wearing it out.

You have 3 stock 372's blowing 190?

 

[jmssaws]

You have 3 stock 372's blowing 190?

No sir

 

[aikensjc]

I do love cheap saws with scored p/c they always seem worth to fix imo

 

[TreeTangler]

No sir

Ah, you have 3 decked or popped 372's blowing 190.