died on the dyno. your veiws please

[delatlanta1281]

i built it. i plastigauged the shells and the one that went was the tightest one but still within spec.

all oil ways were de greesed and blown out.

new bmw pump.

Dumb question, but you did use assembly lube on all bearings and parts that are touched by other moving parts? That'
s gotta be bad part/ assembly/ starvation. what do the valves look like in that cylinder? If it was a timing problem, there would have to be another piston with damage no?

[urbancynic]

I've had brand new oil pumps fail on me before. Luckily I caught it immediately, but still....

That sucks man.

[329jay]

1) incorrect assembly
2) debris in oil /passageways
3) lack of sufficient oil pressure for whatever reason

i built it. i plastigauged the shells and the one that went was the tightest one but still within spec.

all oil ways were de greesed and blown out.

new bmw pump.

[nando]

1-2mm will definitely lead to head/piston contact. An engine designed with a good quench area (like an M20B25) doesn't leave a lot of room between the piston crown and combustion chamber. 5-6mm? that's like a 1960s inline-4 with flattop pistons..

[AndrewBird]

You obviously haven't been around too many engines. Rod bearings fail, pistons start stroking 1 or 2 mm more than normal, piston hits head, compresses ring land, and massive blowby/leakdown occurs.

I suppose so. I wouldn't think 1-2mm would make the piston hit the head, but 5-6mm like the OP has would. lol That is a VERY spun bearing. Frankly I'm a little surprised it would still run and/or didn't break something internally.

[tg318is]

Wow! That sucks mate!

[Mercury[BKM]]

Damn, i'm good.

toot toot! good call lol

time for the re-rebuild =(

[LJ851]

You obviously haven't been around too many engines. Rod bearings fail, pistons start stroking 1 or 2 mm more than normal, piston hits head, compresses ring land, and massive blowby/leakdown occurs.

Damn, i'm good.

[LJ851]

1) incorrect assembly
2) debris in oil /passageways
3) lack of sufficient oil pressure for whatever reason

[Massimo]

That sux dude. I will be interested to know the cause of the problem.

[kingston]

Holy SH*T!!

[nando]

you spun a bearing, severely.

[329jay]

the pics arnt great i know but look at the way the shell has been rolled thin and pushed up the sides of the rod. the piston has touched the head obviously because the bearing is so thin. i have spoke to some one about the shell and have an idea what caused it. im sure you will have an opinion on it.

[ROLLingKING]

you got this bruh..pull that motor apart and play doctor!

bring it to life again!

[Good & Tight]

Sounds like there was something wrong with the engine before tuning it. Who rebuilt the engine?