Thread: crazy knock in 400 chevy sb

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I made the ultimate mistake! Went on a road trip in my 1985 CJ-7 Jeep, has a transplanted 400 chevy sb, and I forgot to check the oil. She had no oil, overheated and I pulled over thinking I had seized the motor. I bought some oil, topped it off, and it started with hesitation. She'll run, but it sounds like someone is playing spoons under the driver side valve cover. Is it a valve? lifter? did I bend a rod? What do you think?

If it was out of oil I would put my money on a spun Rod bearing.
Been there and done that. Not that it could not be up in the valve train but I would bet otherwise. Drop the pan and wiggle the rod ends, that is easier than going thru all the rigamaroll of trying to track down a noise that may or may not be in the upper end.If nothing is wrong then bolt the pan back on,count yourself lucky and then start the process of elimination up top.

Have a good one,
Dan

yep It sound s like it time to get your hands dirty . sounds like a spun bearing Ive got to agree with Laxfan