fatjoe10

Hi all, I just pulled the head off to replace a blown head gasket, and I noticed that cylinder #2 has a scratch running all the length of the piston travel. Yes, it catches my fingernail. I am aware this is bad, but I have not found a definite answer. Also, my head bolts looked thin, as is someone had squeezed them in the middle. Again, heard about it, but I am not an expert. As always, help is appreciated, thanks.

Sleeper2000

[QUOTE=fatjoe10,Jun 14 2008, 05:30 PM]Hi all, I just pulled the head off to replace a blown head gasket, and I noticed that cylinder #2 has a scratch running all the length of the piston travel.

fatjoe10

Hmm... I was running the IP 3mm gasket. The gasket looked perfect except for the paint flaking off between cylinders. To me that looked like the head lifted off the block. Causes? I had a couple of instances when at WOT when shifting from 4th to 5th, the gear would not engage, and the car would bounce off the limiter really hard. I changed my tranny fluid and it corrected the shifting problem, but I guess damage was already done. Previous to that, had zero oil burning. I realized the gasket was blown because after I had come out of a restaurant, upon starting the car, there was this white cloud of smoke coming out the exhaust, and it had the sweet smell of coolant... also, no heater. However, the car had been running perfectly fine, there was no way I could've known if it wasnt for that incident. I was in the process of getting Modifry's temp gauge fix, as I run AEM EMS, so no way to tell if I overheated first, or the head lifting caused the leak. As a side note, where to get the AEM software to communicate with the EMS and pull logs?

ChefJ

You may get more info on this in the FI forum although this is a uth kind of subject. you should be able to see a line or lines where the coolant was blowing by the gasket. This is the "blown" part of the gasket. Its not always noticeable to an untrained eye though.

Nyther

if it's a deep scratch that catches your fingernail.. it's toasted!

I will need to get a new bottom end.... since the sleeves are FRM material you won't be able to remove the scratch and put a slightly overbored piston in..

this sucks bigtime!

Sleeper2000

Man, without looking at it, I can't really say. As little as 0.001 can catch your finger nail... My immediate concern would be the cause. Was #2 where the coolant went? If so, is the scratch in line (vertically) with the leak?

From what I know so far, you have 3 possibilities:
1) Broke Ring - from coolant entering combustion chamber?
2) Particulate scoring - from a piece of metal or whatever....
3) A crack... I've never seen one due to anything I've seen so far in this thread - but, with this relatively thin FRM liner and the big question mark on where the coolant went....

Bouncing your rev limiter a few time didn't cause this. If you had a piston through your hood, or a rod sticking out of the block - yes. Blown head gasket, scored cylinder, No.


Sleeper

edit: typo