was out the other night testing the new gps and a possible fuel pump problem when she bogged down and started knocking. this is the result. fortunately we rebuild these where I work and I can do 90% of it myself.

What am I supposed to be seeing? Excessive corrosion / britttle / porosity on the top of the piston? Am I missing something? Picture isn't as clear as...

LOOKS GOOD TO ME ><><

Is it a hole in the bottom liner ? :confused:

47729

Only one hole? I did a much better job when running at 5000 RPM, holes everywhere!

i LIKE HOLES

Is it a hole in the bottom liner ? :confused:

47729


Ahh - can't see that on my screen

piston is detonated. caused by preignition. not sure if it was from lack of cooling or lack of fuel until it comes apart. the hole in the bottom liner is a port. supposed to be there. I will put up a picture of what the piston should look like tomorrow when I work on it again. if I had kept running at high speed the piston would have a big hole right in the middle of it. motor is going to get a cylinder hone job and 4 new pistons rings etc. I will try to put up some pictures as is comes aparts and goes together.