tripevans

This picture was taken of the right side of cylinder 1. The left side has the same spot in the same location. Cylinder 4 has the exact same 2 spots in the same locations. I haven't rotated the crank to check cylinders 2 & 3 yet. The spots feel smooth with the surrounding area. I am wondering if these polished areas are ok or require intervention. Im also wondering how they got there in a small circular confined area unless the cylinder wall was proud in that one spot. Any ideas?
Don't know the compression or if the car was burning oil...just went in to replace head gasket and do some routine maintenance on the valve train.

Prospeeder

To me that looks like the engine got really hot and started scuffing the walls. Piston expands too much and no more room. It should be ok, but it may use alittle more oil than it did before.

motoguy128

Didn't one person on here note that when replacing the pistons and rings for oil consumption issue, they found a broken crankshaft main bearing bolt. I wonder if when that bolt fails, there is unequal pressure on the crankshaft and the pistons end up a little off center.

But I'm not an engine design engineer or a mechanic, so I don;t know if that possible, so not trying to alarm you. But one of the items on the replacement list is a new front main Bering bolt. I'm just wondering is this is a known issue and part of the reason for high oil consumption.

motoguy128

Is that some damage to the top of the piston that I see? looks like a nick or something? Looks like some sort of deposits on top of the piston right in that location.

the_duke

No expert on these engines but I've experienced this on other motors. That is where the piston skirt rubs on the cylinder wall when it reaches TDC and begins coming back down. The only way to know how bad it is would be to measure it.

Nyron

First thing would be to messure inside where piston sits check for any damage remove piston and check for any damage if not change oil rings and compression rings