Thrust Bearing Clearance

What is the maximum Main thrust bearing end Clearance is acceptable for a 600 hp street driven engine ?
When We put engine together we had 0 clearance to we sanded bearing down till we got .005 and finished engine. After 1000 miles of driving got engine pulled to modify Oil pan checked end play last night and now I have .012 . Thanks

when you put the main in did you smack the front and back of the crank to seat the bearing? I have never sanded a bearing...

We did several times . After that we got .001 thought that was still to tight . I know the spec. Say .003 -.005

The Ford shop manual says .004"-.008" end play.

I have sanded one side of lots of lower thrust bearings going into a line honed block where the thrust cap was not resurfaced exact. Just the lower though; not the entire bearing.

Is .012 to much ? I have never had any problems with this issue before. Sorry Lem you are correct , I wen't back and looked also . I was going off memory !! Lord knows the memory is not as good as it was 20 years ago . Lol

I think that was my problem it was line honed and I sanded the whole bearing .

OldRed70 wrote:Is .012 to much ? I have never had any problems with this issue before. Sorry Lem you are correct , I wen't back and looked also . I was going off memory !! Lord knows the memory is not as good as it was 20 years ago . Lol

The memory thing just keep slipping away as you get a little older until someone refreshes it for us

Absolutely Jim , Lem did it for me !

rmcomprandy wrote:I have sanded one side of lots of lower thrust bearings going into a line honed block where the thrust cap was not resurfaced exact. Just the lower though; not the entire bearing.

That's the deal.....is 'it' the upper or lower....the front or rear of the bearing flange that needs 'love' ?

i did the same thing, mines been at .012 for 6 seasons now....... not saying its right but it will damn sure work.

richter69 wrote:i did the same thing, mines been at .012 for 6 seasons now....... not saying its right but it will damn sure work.

Id rather have it a lil loose than tight. Especially in a race engine. I prefer between 5/10.

What did you use to sand the thrust bearing surface?

1500 grit sandpaper and a thick piece of Glass

With WD-40 and go slow.

Yes Lem we used WD-40 and also sanded in No particular pattern

Got mine taken care of last night. Problem was in the cap. Took the #3 cap off and had .006 clearance. With Cap on and 15 ft lbs tq, I had to push on the pry bar to get .001 and had trouble rotating the crank by hand.
After sand paper and WD, I now have .004 and the crank rotates freely with the caps torqued to 110.

Just my opinion of course but while your at it I would go at least another .001 for shits and giggles Alan.

Yea, I was thinking the same thing.