What would be an excessive amount of end play on a small block?

The MP oval track bible has a spec of .002"-.010" (crank end play)

Ours is like.032. Would that cause loss of oil pressure too? Also what causes it to wear that much? Car has about 5 thousand Street miles and 225 quarter mile passes on it

Stick or an automatic ?

Automatic. B&M 3000 stall. Can only leave line about 2300 though.

Several different things can caused the thrust bearing to wear out, one is the converter being ballooned, another is not enough clearance on the converter to the flexplate to start with and possibly several others that I can't remember right now. The fix is to have the thrust surface welded and repaired or replace the crankshaft We use to have a bad thrust surface hard chromed but a lot of that went away when the crazy enviormentalist got thier way with the local goverment agencys shutting the local chrome shops down

What's the most end play you could run safely? Mostly just running on street anymore. Was just going to put new bearings in it and go.

What is the endplay with a new thrust in it?

If it comes back into spec, check the convert pilot to crank register fit.

Kevin

Agreed, & I'd measure the flange thickness of the old/new #3 thrust bearing halves. As you know you'd want to do a thorough cleaning prep like you would on a regular rebuild. No thoughts/opinions on the cause. Holler what develops

Going to machine shop this week. Will let know what we find out. Thanks!

My 360 ate a thrust in 2014. I have not figured out why, no converter balloon, plenty of clearance from the flex plate etc. Mine was running great, I happened to notice the balancer moving while idling in the driveway one day. I never did measure how much it was out but it was ALOT I am surprised the belt stayed on.

I did what nobody should ever do in this situation because it was two weeks before drag week and I wasn't going to miss it. I bought a crankshaft kit from Orielly for $200 that came with a machined crank and bearings. I slapped that thing in and stuck it back in the car and put 1200 miles on it and raced it at 4 tracks in one week LOL. It has now done two drag weeks with that crank and has run a best of 11.16@119.5 MPH. I had pulled this motor out last summer but ended up havng to put it back in for drag week again due to problems with the other motor. We checked the thrust before we stuck it back in and it had .005 so I have no idea what happened to it before.

I have seen mention of a different thrust bearing for the earlier pre 76(i think) 360's but I have never confirmed this. When I bought the crankshaft kit for this motor I used a 1980 dodge truck to tell the parts store guy what I wanted. I have a 76 model block. Its possible I had the earlier thrust bearing in it before but I have never confirmed this, I have just seen it mentioned on here before.

Diameter of the thrust bearing flange is larger in the later setup.

Probably because the earlier design had a problem with thrust bearing wear.

Not sure you can run the later bearing in the early block, I know you can run the early bearing int he later block though.

the block bearing saddle & cap the "recess" was enlarged in ~'74 to use the larger thrust flange #3 bearing (my 6-19-74 block is that) and hold your current bearing halves together like a clamshell and the OD for the later ones is a hair under 3" (2.91" comes to mind). I think your bearing just failed cuz stuff fails (tho I would for sure do the ballooning & other checks if you ain't already) & I hope with new bearings that the endplay is within specs. there might be a NAPA truck bearing with an even slightly larger OD (not sure) but I doubt if the flanges are thicker as unfortunately that would be a "problem solver" specific part. but there might be such an animal out there. holler how it goes EDIT the more I think about it the more I think there would not be such a part & (my) reasoning being is that the amt of wear on the crank could be anywhere so how additionally thick a bearing should a mfr make available (the crank would still have to be turned to get the clearance right). this is an infrequent occourance & likely the crank will have to be welded/turned or source another crank unfortunately

Back in '76 or so I bought a 383 powered '70 Cuda. The crank would move so far the motor would bog some at a certain rpm. What kept it from locking up I'll never know. Anyway, we pulled the motor, turned it upside down and put a new parts store crank kit in it. Put it back in the car and never had a problem with it. I drove it for a long time..hard, then sold it. The next owner never had a motor problem out of it either. I guess the oil filter took care of any metal in the motor....
Dallas