wow, thats some serious damage. Looks like you ran lean/had preignition. I asked before but got no response, did you change out your banjo bolts to the revised 4 bolt design?

 

Says he's running a 2002 in his profile, pretty sure Honda had moved all the s2k's to the new banjo bolt by then. I think only the 2000 and 2001 had the old bolts.

 

I think it was during 2002 that they switched over.

 

That's what I thought too

 

Sorry I didn't answer, I know you were trying to help.

The banjo bolts would have nothing to do with this. The tops of each piston are melted and those never see any oil, so that would not be the problem. I didn't change the banjo bolts, and I am not sure if the previous owner brought it to honda for the recall.

 

sleeve the block.

lesson learned. move on

 

Na I have a lot of confidence in a stock motor, this was obviously not a weakness of the motor's internal components. Even aftermarket pistons would have failed in this situation.
I just need to find the cheapest way to get another stock motor up and running. Probably with some arp's.

Is there anyway to test the gas that is in the tank? To see if it was a lower quality than it should have been?

 

it was halfway through 02 that they changed to the revised banjo bolts. Some people said it could be measured by vin, but some late '02's were found to still have the older 2 hole bolts.

 

No doubt the less efficient banjo bolts weren't the main cause of this failure, but i'm sure it wouldn't have helped. I had a similar 4th cylinder failure due to the older bolts, and my block looked similar to yours. BTW, there was no recall with the bolts in the US. It was only a recall in Europe.

For the aluminium to melt like that, the temperatures in the combustion cylinder would have to get very hot! Whatever you do, make sure you check all parts of your system before throwing a new motor in. Good luck!

 

Just curious if you did the free air calibration on the o2 sensor before you put it in and tuned? If you didn't, the A/F's you were seeing (say mid 11's) could have in fact been high 12's due to the wrong readings.