Thrust bearing ?

 

Is this the thrust bearing?

 

Here are the bearings and crank bearing surface.














The first pic shows a questionable crank journal and a few pics later is the corresponding bearing, but nothing that would lead to chunks in the oil.

This process got me to wondering how fast a team could machine and rebuild a motor like this. About an hour to disassemble (not the head fully). If I had a machine shop and a way to Nikasil the bores I think it could be done in a weekend.

Heres the tops of the 2 pistons that correspond to the pitted combustion chambers.



The ring lands are not seized up in either pistion

 

The crank and connecting rod bearings seem damaged. Did this engine have a situation where it was starved for oil?

Yes, that is the thrust-bearing halves.

Thanks again for the great photos! Sorry about the engine.

 

Thanks for the feedback. No known oil starvation. It’s been boosted for the 40k miles that I’ve owned it. Recently turned up the boost. May have been the last straw for a tired motor.
As of now, I plan to send the block to Milenium Coatings for Nickasil, and replace all needed parts, and have the balance of the needed machine done locally. The F22 I swapped in was rebuilt and has zero miles, but I didn’t do or monitor the rebuild, so I’m motivated to have this motor ready to go.

 

Those chunks in the pan look like the main bearings that failed on my engine. The funny thing is the bearings have a way to smooth themselves out despite blowing chunks. I say it was a main bearing and the motor had some oil starvation. Are the cylinder scoring deep enough to catch your fingernail ? I know some marks show up on the cylinders in some conditions but sometimes they are not deep enough to be an issue unless you can catch a fingernail on them and feel the scoring. As for the piston marks did you ever have a broken spark plug tip ?

 

Here is the bearing material up close that was in the oil pan. The last two pics are idle the front and back of one of the big metal bits.
The black bits are not silicone. They are hard.

 

Copper-brass-colored bits are usually remnants of bearings.

 

Can’t find the source. It is what it is, just hoped to find a smoking gun source.

 

Do you still have some of the old oil? Have an analysis run. That'll help figure out which metals were most worn.

Then, check the Net for bearings that use that metal.