DaveD89

I have a 89 5.0 that I rebuilt 10,000 kms ago. I had to take it off the
road because of noticeable crankshaft endplay.Before I start on the
engine again I must discover what is causing this problem. This is also
the reason I rebuilt it the first time.The wear was on the rear thrust
surface of the center main bearing.I installed an aftermarket clutch
quadrant and cable and made sure that there was lots of free play.
Any ideas would be appriciated.

86HOGT

Do you ride the clutch a lot? Hold the clutch in at Stop lights?

roundman

you need to measure the length of the crankshaft between the thrust bearing faces, spec length is 1.137"-1.139" which should yield a crankshaft end play of 0.004"-0.008" with a service limit of 0.012". the runout on the crank thrust faces should not exceed 0.001". they make thicker thrust bearings to make up for machining done to reface the crank, so you can buy a thicker thrust bearing to get the end play back in spec.

vfast

this is why the measurement should be always checked....most people don't and I'm sure this being your first you just over looked it....replace all the mains when fixing this problem and taking roundy's advise

DaveD89

Thanks for your responses so far. The weird thing about the excessive end play is that it is something that you would expect to see if you rode the clutch a lot, but I don't. I have been driving standard since I was a teenager so that shouldn't be the problem.This is the second crank that I have put in my engine. The first crank had about an eighth of an inch of end play when I noticed that it was a problem so I took it out and got a new crank and put it in. I got it machined at the same shop as the first one so maybe their workmanship has something to do with it. I don't know. Anyway, the second crank is now showing about .030" of endplay. When I put the crank in I made sure everything was in spec. Any more ideas?

roundman

something still ain't correct if you got .030" endplay with that crank. you need to get a thicker thrust bearing insert or get the crank welded up and turned back down to get the right length on the thrust bearing journal. that much endplay will just beat the bearings out of it really fast.