Pinion Bearing

[Fran Blacker]

Think there 2 small cut 180 degrees apart out where you'd hit with a punch to knock out the cup. If you could get hook in the cut out and slide hammer it out side to side.

 

[Stumper]

It’s a 742 case and from what I hear does not need any particular preload. Just putting it back as it cam apart and torquing to spec?
Ill check at Napa to see it they have any type of small inside puller. If not I guess the race stays for now. I don’t see or feel any pitting or damage on it.

 

[SlinktRR]

I bought axle seals from Dr diff and installed them, but one of them I mangled while installing and I went to get another seal from O'Reillys. The Dr diff seal is much better quality, I returned the oreillys and ordered another one from Cass. It was cheaper as well, $4 vs $10 from the parts house.

 

[RJRENTON]

I never heard of anyone removing the race without removing the center section and driving it out from the inside. They don't come out that easily.

It's quite involved setting up the pinion preload. The proper preload on pinion bearings are measured in resistance using a inch pound torque wrench with the center section/carrier removed. The use of shims sets the preload. Removing the yolk to replace the seal and reinstalling it is mostly guess work for the proper preload. Marking the nut before removing it might get you in the ball park when re-installing it but it's just a guess. Also if your rear used a crush sleeve you should replace it with a new one to do it right. Again this should be preformed with the center section removed.

Can you get by with what you're doing? Many have but it's not totally advised. If you plan on leaving that race/cup in there, inspect it for a pit that matches the one on the bearing. More than likely that rear sat for some time and moisture in the top half cause the rust. The teeth on the ring gear that wasn't submerged in lube probably has rust pitting also. If the cup is pitted a new bearing may not last that long either.

Just throwing some thoughts out there.

EXCELLENT ADVICE....yes....he should pull the axles snd remove the center section and do it correctly. The pinion bearing's preload is determined by rotational torque value and adjusted with shims. Installing a new cone assembly (roller assembly) in conjunction with a used cup (bearing race) is never a good idea...but has been done to save $$$ and time.....but invites future problems..... Just my opinion of course.
BOB RENTON

 

[Fran Blacker]

Get a piece of PVC tube that is slightly smaller than the seal.

 

[Stumper]

What a rookie mistake …. My case is in fact a 742 case so I ordered a HM 803149 bearing for it. Came in today and I instantly realized I screwed up. The bearing that was in it was a HM 89443 - for a 1.315” pinion shaft.. Someone had apparently changed to the smaller diameter pinion at some point and I didn’t bother to check…. Fortunately the local parts store had the 89443 in stock. So now I’m wondering what else inside is not 742?

 

[john-9]

you have the right bearings ,, HM803149 cone ,, HM803110 race is the rear pinion bearing ( nearest the carrier ) ---- HM89443 cone ,, HM89410 race is the front pinion bearing ( near the yoke ) for the 742 case -- no one changed anything -- as the gear sets for the 741 , 742 , 489 cases do not interchange . but i would strongly suggest you rebearing the whole differential now is the time ,, unless you like doing things twice.

 

[Stumper]

‍ - the terminology I was used to was inner and outer pinion bearings with the outer being the one near the yoke. That’s what I went by when I ordered the new one.
I hear you (and others) on doing a full rebuild of the rear end but for now I’m going to see how it does with a new bearing and seal. If the rear end was out Of the car I’d tackle it, but I’ve got a number of other things to address on this car over the winter. Maybe next winters project…