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Suss Piston

180or200

By 180or200,
in Engines & Forced Induction

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180or200 Proficient

180or200

Posted
Posted

Hey guys

my 25 turned into a kettle Friday night, head gasket blew, looks like its been on the way for a while, little bit of corrosion on the block under the gasket, looks like the metal ring on the gasket has caught the edge of the piston, not sure if i should pull it down and go for broke or just fit a better gasket and see what happens!! has anyone seen this before?

post-34685-1244983633_thumb.jpg

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The Dan Grand Master

The Dan

Posted
Posted
Hey guys

my 25 turned into a kettle Friday night, head gasket blew, looks like its been on the way for a while, little bit of corrosion on the block under the gasket, looks like the metal ring on the gasket has caught the edge of the piston, not sure if i should pull it down and go for broke or just fit a better gasket and see what happens!! has anyone seen this before?

post-34685-1244983633_thumb.jpg

If that's the inlet side, it looks like the beginning of a piston melting.

Have you looked at the gasket in the same position to see if it also has similar damage? Usually the stocko head gasket will let go if detonation has been an issue for some time and the piston can cop some damage from the detonation but not before the gasket blows.

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The Dan Grand Master

The Dan

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Righto, well it won't be a melted piston. Considering the damage on the gasket and the limited amount that can be seen on the piston, if it were my car, I'd be pulling the engine out and replacing or repairing it.

You could leave it if you wanted to but only the magical pixies know what damage could occur.

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Duncan Grand Master

Duncan

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has the motor recently been rebuilt? piston looks very/too clean? was the gasket the right size for the bores if it is overbored? did you use both of those alignment thingies that sit around the head bolts

personally I would pull it apart for sure. they may be able to save the piston with some light machining but you don't want it scraping up and down the bore looking like that.

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Guilt-Toy Grand Master

Guilt-Toy

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if you move the piston down the bore can you see any scores or marks ?

I would be pulling this engine appart regardless. I would dare say the rings are cracked as well.

The piston is very clean because this is a E85 engine :banana:

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180or200 Proficient

180or200

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has the motor recently been rebuilt? piston looks very/too clean? was the gasket the right size for the bores if it is overbored? did you use both of those alignment thingies that sit around the head bolts

personally I would pull it apart for sure. they may be able to save the piston with some light machining but you don't want it scraping up and down the bore looking like that.

she's all factory, so i'm sure the gasket was the right size.

if you move the piston down the bore can you see any scores or marks ?

I would be pulling this engine appart regardless. I would dare say the rings are cracked as well.

The piston is very clean because this is a E85 engine :banana:

cant see any scores on the bore at all, just a few water marks, it is cleaner than the rest, most likely the steam and un-burnt e85 cleaning it!

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