Perfecto, thanks!

 

You meant if the metal impellers carved all the way through the case causing the pieces to fall in sump? It would have had intermix big time and mucho noise before that but interesting thought, though.

 

I don't think that's what he meant.

 

Correct, it's not. I was reading two forums at once ( BMW/Here) and thought we were talking about intermix here...whereas the intermix discussion was on an M3 thread I was reading at the time. I'll not make that mistake again. I look stupid and apparently Imo000 thinks I sit in a corner drooling on myself. OP good luck with your solution.

 

I don't think you are sitting in the corner.

 

Update: This is cringely's engine. I've dropped the oil pan and drain plug and found lots of debris. The oil has a gold glitter in it. I've collected and stored all the debris for further analysis. I should find more clues of where these pieces came from when I tear down the engine.

1. All the ferrous debris in the oil pan



2. 5 pieces of ferrous metal. They don't look like they are from the IMSB though



3. Another shot of the 5 pieces.



4. All non-ferrous debris. One small piece of aluminum and one piece of sealant. The rest look like chain pad material.



5. Another shot of the 5 piece



6. Another shot of the 5 piece



7. Another shot of the 5 piece



8. Magnetic drain plug



9. Oil pan



10. Another shot of the 5 piece

 

Ahsai, is this your motor or the Op's? I'm a bit confused...

 

It's cringely's engine which has the LN bearing. I bought his roller.

 

Ah gotcha. It will be interesting to see what else you find. Are you planning on taking the LN bearing apart to see if you see any scoring in the races?

 

Yes, I plan to do a full tear down and hopefully find the cause of the failure. Will need to find time to drop the engine first though.

 

Thanks for posting the pictures, very interesting. Guess when you have material on the drain plug you know it:

 

Oh wow Ahsai! That's a lot of ferrous material and chain pad material. It will be interesting to see what you find went wrong. Keep us posted. Thanks.

 

That's a lot of debris. I'm also interested to see what was the MOF.

 

Yea, tons of shavings and fragments. I look forward to the teardown too.

One thing interesting is out of the 5 largest ferrous pieces, one piece is not shiny. It looks like it just chipped off somewhere while the other pieces were clearly ground and mangled by some moving parts in the engine. BTW, I checked the oil filter port on the engine and found no shavings there so it looks like the oil filter bypass valve wasn't tripped so the shavings didn't get pass the oil filter. Will keep an eye on it when I tear it down.

I think this engine could have been "saved" if it had been equipped with an IMS guardian. Look at the debris collected at the mag drain plug, the guardian would have warned the owner a lot earlier than this terminal stage. Granted the engine would still need a rebuild but at least the damage should have been a lot less if the engine had been stopped in time.

 

Regading scoring races on the IMSB, my expectation is the wear will be concentrated on the bottom half of the inner race because the chains are constantly pulling the IMSB up toward the crankshaft, especially when the engine is running and the tensioners are all pumped up. The inner race is fixed to the engine casing while the outer race (fixed to the IMS) presses UP against the *****, which in turn press on the lower bottom of the inner race.

I show a 5-chain here but the 3-chain 3.6 is similar