Damaged piston

[Blk04MM]

Helping my brother in law clean his side of the shop I can across this on one of his short blocks.

What do you think caused this?

http://i1300.photobucket.com/albums/ag82/blk04mm/Mobile%20Uploads/image_zps6677530a.jpg (http://s1300.photobucket.com/user/blk04mm/media/Mobile%20Uploads/image_zps6677530a.jpg.html)

[Zack]

Detonation most likely

[RacerX]

Rod bearing is gone. Piston gets thrown too high and starts hitting the head. That's why there's a line across the lower #3 in the pic.

[Blk04MM]

Detonation most likely

Looks like it melted or something. Maybe even broke off


Rod bearing is gone. Piston gets thrown too high and starts hitting the head. That's why there's a line across the lower #3 in the pic.

That's a piece of the piston missing not just a line lol

[Zack]

Rod bearing is gone. Piston gets thrown too high and starts hitting the head. That's why there's a line across the lower #3 in the pic.

No.

34567890

[RacerX]

No.

34567890

That's what I get for looking at the pic on my phone. ;)
That break line is about where it would hit metal on the head if the bearing and crank journal are being eaten away. You'll have a matching one on the other side too though.
Holy crap! Those cylinder walls are caked!!!

[Blk04MM]

No.

34567890


That's what I get for looking at the pic on my phone. ;)
That break line is about where it would hit metal on the head if the bearing and crank journal are being eaten away. You'll have a matching one on the other side too though.
Holy crap! Those cylinder walls are caked!!!

So what else would be "damaged" under here. He said he was going to rebuild it but now it's just sitting and he thinking of selling it.

[RacerX]

Could be anything. Cylinders walls may be scored too deep to bore. Crank and rod may be no good... Or you may just need one new piston a hone, bearings and rings. Zack is right and you wont know until you fully crack that open.

[Blk04MM]

Could be anything. Cylinders walls may be scored too deep to bore. Crank and rod may be no good... Or you may just need one new piston a hone, bearings and rings. Zack is right and you wont know until you fully crack that open.

He or I will get to it this week and update.

[Marauderjack]

Looks like the ring land on the thrust side gave up from detonation to me but no matter what the cause it ain't good!!:shake:

[JohnE]

Looks just the same as my factory engine did from some detonation at wot with the blower. Slight fuel delivery hiccup is costly.

[Blk04MM]

Finally pulled it apart.

Surprisingly the cylinder walls seem to be unharmed. The piece of the piston looks to have broken and either turned down to fall to the oil pan along with The lower pieces of the piston or turned to dust. Some other pieces fell to the oil pan and go sucked into the oil pick up. The rod is fine too not bent at all. So I'm guessing it wasn't a blown gasket.

Just gota send everything off to be cleaned

http://i1300.photobucket.com/albums/ag82/blk04mm/Mobile%20Uploads/photo2_zpsa9524394.jpg (http://s1300.photobucket.com/user/blk04mm/media/Mobile%20Uploads/photo2_zpsa9524394.jpg.html)
http://i1300.photobucket.com/albums/ag82/blk04mm/Mobile%20Uploads/photo1_zps078fc635.jpg (http://s1300.photobucket.com/user/blk04mm/media/Mobile%20Uploads/photo1_zps078fc635.jpg.html)

[RacerX]

New piston, hone and deck the block, re-ring the pistons, new crank and rod bearings and I would either buy a new oil pump (only about $80) or at minimum, take that oil pump apart. Those Torx screws are in that pump really good too! ;)

[Blk04MM]

New piston, hone and deck the block, re-ring the pistons, new crank and rod bearings and I would either buy a new oil pump (only about $80) or at minimum, take that oil pump apart. Those Torx screws are in that pump really good too! ;)

New Crank?
That isn't damaged either.

[Blk04MM]

He Might just sell it knowing it isn't bad as he thought

[Zack]

He Might just sell it knowing it isn't bad as he thought

Its worth about $120

[Blk04MM]

Its worth about $120

Definitely won't be sold for that amount. It'll be sold once it's received back from the machine shop if it is sold.