8 3/4 bearing cap gap

[fmuncey]

Rebuilding a 8 3/4 742. The problem is there is a .030 gap between the carrier
bearing cap and the carrier bearing cone. This does not seem correct. This gap thows the
tooth mesh pattern off when the cones move.
Is this normal?
Would there be a problem putting a shim in the gap.

[Moparal]

There could be a couple of problems. But the caps should fit flat and snug with no shimming.

Your adjuster is not seated square and so it isnt allowing a full seat, or you may have the wrong bolt type. Number 9 housings take a shorter bolt with a different shank than a number 2 housing does. #2 housing has longer bolts.

And see if the bearing caps are marked with a 1 or 2 punch mark. The spanner adjuster must turn easy with little effort before tightening the bolts down all the way. If not, the bearing cap wont lock down and seat in.

[moper]

Its very easy for the cones to slip and get a little cocked in the bore. I like to snug the cap bolts by hand and then use the adjuster to help align the threads.

[fmuncey]

Upon further examination. With the cap tightened to spec and just the cup installed(no adjuster or ring ) there is still a gap. The adjuster screws in easy and it also has a gap. I even swapped the caps and there still is a gap. The cup fits snug in cap, also fits snug in the carrier, but when the 2 are put together there is a .030 gap.
I suspect these are not the original caps.  There is damage to the axle housing inline with the ring gear. There persion that rebuilt it before me either did not notice or care about the gap.

Options: 1. Machine .030 off the caps. Hoping everything is stays aligned.
            2. Buy a carrier

[Moparal]

So you are saying with the race installed, and not with the carrier, the main cap will not pull down square and flat?  Is this true to both sides or just one side (ring gear)  The cap may of been damaged and spread. If someone local with rear end experience could look at it, that would be helpfull, but machining them down yourself will make the gap larger.  If there was a breakage problem before you got this unit, I might would just find another center to use.  What number housing are you useing?  Pictures would also help

[fmuncey]

Working on some pics. Are cap and carrier a matched set. I mean you can not exchange caps from 1 742 to a different 742 carrier?

[quagmire]

Yes, they are just like engine main bearing caps.  The caps and center section are align honed together.  You can't mix and match them.

[fmuncey]

Thats what I thought, cap and carrier are a set. Here is a pic and a drawing with dimensions.
I am going to look for a machine shop, then try and hunt down a carrier.