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no thrust bearing clearance

hi guys, currently assembling my first engine. started with the bottom end, main bearing clearance looks good via plastigage but there is literally no thrust bearing clearance. I am using ACL race bearings (std) and there is no back and forth play on the crank at all and I cant even fit the 0.004 feeler gauge between the crank and the bearing. However, the crank does spin really easily so I'm sort of lost. Any help would be appreciated.

Quote:

Originally Posted by niketh (Post 1636699)

Do you still have the old thrust bearing that came out to check clearance? If that's good, just use an OEM or another aftermarket thrust bearing. They are inexpensive and doesn't take that much abuse that you need the ACL's.

I never managed to get a feeler gauge in, surfaces nearby are too rough. Only a dial gauge on the end showed me the crank was moving, and with a fair force needed.
If anything is in backwards it can remove free play, but usually makes it harder to spin too.