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View Full Version : Main studs spin when loose? & Clock the Cam Bearings?



MI6TA
04-02-2014, 11:05 AM
Hey all, I've currently got the crank rods and pistons assembled. When we were plastigauging the crank everytime I would take all the nuts back off of the ARP Main Studs I purchased the studs would spin as well as the nuts. The ARP instructions say to just hand tighten them in to the block, and when it's torqued to 80ft lbs of course they aren't spinning. Just wondering if that's common.

Next, My father read somewhere on a forum and in a book about LT's that you're supposed to clock the cam bearings. Instead of aligning the cam bearings with the oil feed holes, you position them at 5 o clock and the main is at a different position, but not aligned with the oil feed hole. It's supposed to keep oil pressure up during high RPM? True or False?

As my engine is, the crank spun freely when torqued. The cam bearings were aligned, but then we took em out and put em back in with the 5 oclock position. Same bearings used.

firebird_1995
04-02-2014, 11:43 AM
I used a dab of blue loctite on the threads and "tightened by hand" with an Allen wrench, as tight as I could. But yes, I've had head studs spin loose while taking the nuts off. I don't think its a big deal. As far as the cam bearings go, I've never heard that. I'm interested to see what others say about it. I could see by not aligning the holes it would force the oil around the bearing and possibly offering some additional cooling.... but I'm just speculating.

MI6TA
04-03-2014, 03:58 PM
We put some ARP preload assembly stuff on the studs but no loctite. Thought about it though...

I guess that's the thinking with the bearings, I just am concerned that installing them, taking them out then reinstalling would damage the outside of the bearings?