I messed up my #3 main bearing in my f22 today. I dont know what happened i measured every thing i blue printed every thing. my clearance was .0018 on that bearing. I think it was the stock crank pulley out of balance and i need a fluidampr or i had detonation. I had tuned the engine on crome and was in the process of tuning with ectune. what do you guys think

 

how long did the motor run before the bearing went? were you precise in your measurements? what instruments did you use? not a tape measure right?

 

About a 100 miles. I used all Starrett and brown sharp

 

Sounds like your block has issues. you need to check the straightness of the mains and get it line honed if it needs it. Could also be a warpd crank too but i doubt. The clearances might be right but one side of the crank journal is scraping one side of the bearing causing it to fail after a few miles on the engine.

 

i think this is what the problem is. I checked every thing but this. I did all the machine work myself. I did notice that sleeves where off like they where twisted about .004. When i surfaced the block. Then i honed the sleeves all true. I ask one of the older machinist at the shop about it he said it must be where it had open deck sleeves. Now we are thinking no the block was twisted. He laughed n sayed i aint never seen a good ole american block twist, we seen them spin the mains and get off but never twist. I guess i have learned to always check the block not just the crank for run out. luckly i did not destroy the rods and pistons.