I test fitted and measured the crank today.when I installed it I noticed that there is very little clearance at flange at no.5 bearing [.0025]this seems kind of odd,is it suppose to be this close?I"m looking at the raised part that goes in the grove in front of the oil seal grove.the crank is all the way to the rear.

 

Oldsmobile Engine Blueprinting Tolerances - Mondello Oldsmobile V8 Tech Manual

"Main Bearing Clearance: .0015" - .0025" MAX., Rear Main .003" (.0025" recommended)
Thrust Main Bearing Clearance: .004" - .010"

I would imagine the thrust main bearing clearance is what you are talking about...how did you measure this clearance?

 

Thrush clearance is good used feeler gage .009.What I'm referring to is in the center of pic the raised part of crank, between the bearing journal and the seal journal, that runs in the cutout .Looks like it should be centered in cutout,but it is too far back .0025 from the block at rear of cutout.jJust wondering if this is normal.

 

I wish I could help...I can't find anything on a specific measurement. I would imagine that as long as there is SOME clearance with force applied then it should be ok. Maybe Brian or Joe can help...

 

thanks ah64pilot,just change the pic to show it better.I do have .0025 clearance,my concern is if front of thrush bearing on #3main wears I'll have metal to metal contact in this area.