Starting to put my engine together, and the thrust bearing will not even begin to go on the billet main cap. I checked them with a micrometer and the cap is .01 of an inch bigger the bearing. The bearing fits the stock cap just fine, so the problem must be the billet cap. Do I need to make a trip to the machine shop or could I use a flat file on the inside of the thrust surface of the bearing? T.I.A.

back to the machine shop. They should have set that when doing the honing

Have the shop fix the main cap, do not file anything to fit on the mains Filing rings to fit is fine, never mains

That is what I thought, I just wanted to see what the consensus here was. I was trying to save myself the 250 mile round trip to the machine shop. It is not worth taking a chance destroying the engine just to save myself some time (and miles).

Thanks guys.

Reid.

I run the 440Source billet main caps and all my bearings including the thrust bearing fit fine. Ron

383man,

These are also the 440 source caps. I have tried 2 different brands of bearings and they both fit the cap like this.


Reid.

Call 440 Source and tell them.

Yes I agree, 440 source should replace the cap, it's not right.

I have already spoke with 440 source. I was told the cap should be machined to fit the bearing.

Mate tell em to read their own web page

directly from the billet main cap description "and the thrust surface is already pre-cut into the #3 cap" says that for the normal and cross bolted ones

440 source should replace!

I bought two sets of billet steel main caps from 440 Source a couple years ago and on one set the #3 thrust bearing fit fine and on the other set it wouldn't go on (like yours). My conclusion was that their quality control needed/needs some work. With that being said, I took it to the local machine shop and they fixed it.

The face is usually final fitted during the line bore - as it has to be a true 90 to the crank center line - take it back to the machine shop - they failed to do the final fit

If he has started to assemble the motor, that means the caps have already been fit to the block........soooo, even if Source does send him a new cap, THAT cap will have to be fit and the line hone redone. That would be foolish. Machine the bearing register and call it a day. Don't step over a dollar to pick up a dime

You might want to rethink your choice of machine shop, thrust surface should be checked and machined when doing the line bore.

Thank you guys for all of the good information. I will be taking it to a machine shop.