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83Blzr62
11-04-2006, 14:52
I am checking the main bearing clearence on my engine and they seem to be a little off. The #5 bearing clearence is about .002", maybe a little under. The #2-#3 bearings are at about .003"-.004". My haynes book says the clearence for number 5 is .0022-.0037 and the others are .0018 to .0033. The clearences on my engine are at most .0005" off . Will that cause any problems? I will have the high flow 6.5 oil pump.

Thanks,
Kyle
83Blzr62
11-04-2006, 16:39
Okay, my dad and I used a dial bore gauge and OD mic to measure my crank and main bearing journal. The od mic said the crankshaft was 2.940" which is correct because I had my crankshaft ground .010"under. The dial bore gauge was set at zero at 2.940 and said that the #5 main bearing was .003" bigger and the 1-4 were all .004" larger. This would make the #5 good and the 1-4 about .0007 too large. Would the larger clearence be acceptable? ALso should I divided the .003 and .004 by two to find the clearence because I need to consider the clearence on both sides?
Thanks, Kyle
Robyn
11-04-2006, 19:23
It will be fine.
If anything run 30W oil and it will love it.
john8662
11-04-2006, 20:55
Both Federal Mogul and Clevite offer a .001" thicker bearing for both rods and mains. What you can do is tighten up the journals that need it and leave the rest with standard bearings.

I'd try and keep them at a max of .003" personally.

J
83Blzr62
11-08-2006, 14:17
My crank was ground down .010", so the bearings that are only .001 over size won't work, so I guess I will have to live with it.
JohnC
11-08-2006, 14:59
I admit I haven't built up any automotive engines lately, but I've done quite a few in my time and personally, I would never put a main bearing together with less than .0025 or so clearance. It just doesn't feel right...

As long as it makes good oil pressure you should be fine. Maybe go with the later oil pump as it has a higher volume capacity.
john8662
11-08-2006, 15:56
For a .010 ground crank, yeah, you're not going to have the option of the .001" bearings.

What brand bearings have you got?

Hmm...

You can either run it as is or find another 6.2L crank that's standard or just needs enough polish to need a .001 bearing (like I did on my '86).

J