How does this piston look??

[Logue]

i'm doin a deal on some je .20 over used for 3,000 miles pistons mounted on 6 bolt rods shot peened rods with a 6 bolt crank and clevite bearings. The guy i'm buying them off of said theres a small scuff on the bottum of the top ring land from removal of the piston. He says it still usable. I'm kind of on a budget on this swap and wanting to know your guys opinon. Does that scuff make the piston unusable.

JJ

 

[my97mitsGSX]

i'd like to know also.. i have a few scuffs on my pistons that were brand new actually..

The car will still run, it may scratch the cylinder walls a little bit though.

 

[Audionuttt]

*Does that scuff make the piston unusable*

No that scuff does not make the piston un-useable. Clean the piston, polish the scuff. The cylinder wall 'seal' is provided by the rings, not piston.

 

[Logue]

i went to the local machine shop and they said the piston is unusable.
he said the piston was not damaged in removal but damaged by detonation.

 

[Defiant]

Looking closely, the bottom of the top ring land may have signs of damage on it- which could well be caused by detonation. At any rate, he's lying about what caused that scuff- you can't do one ring land like that during removal unless something's there to be the abrasive.... such as a fractured ring.

The lilikehood of aluminum pistons scratching iron cylinder bores is rather remote.

 

[psychlow]

Defiant is right, especially considering the side of the piston will likely never contact the cylinder bore.

The only thing I'd be worried about was a ring bending slightly and breaking, or the ring land breaking off.

 

[boost12dsm]

the piston does not look bad but all those marks olmost look like Ping marks caused by not useing good enoufgh gas or just because of not being tuned good " detenating"

may not be right but just what I think, but then again im not an engine builder so who knows

 

[AntixTSi]

How deep are the scores on the piston? The only time that the piston will contact the cylinder wall without causing engine failure is if the bore is out of round. And it will only do this when the engine is cold. This is known as "Piston Slap". When the piston is cold it is smaller, if the bore if out of round the piston can wiggle back and forth until the piston and rings fully expand. the noise sounds similar to lifter tick but more intense. even if that was the case it would be the bottom of the piston skirt that was scuffed, not inbetween the sealing rings. Looks like a ring failed to me.
-Mark

 

[Mirage2LTurbo]

Detonation destroys ringlands, plain and simple. He probably got a little rowdy with his SAFC, and there is the results of it. Don't reuse it, get your money back or make an ashtray out of it.

 

[AntixTSi]

I agree, If the other 3 are ok then you can try to buy one new one but I know that JE usually wont sell just one piston. IMHO get you money back and go for new. Remember build it right once or build it twice.
-Mark