To open or not open the differential..that's the ?

[richberman]

I am wondering if I should disassemble my rear differential and axles. It appears to be in great condition from the outside. The rest of the car was in great shape and was wondering if there is a way of determining if the differential is in need of repair without opening it all up or if I should bite the bullet while the car in in pieces. Someone told me I should drain the oil and look for metal pieces as my indicator....thoughts. And what should I use to refill the oil. Anyone have one of those special tools (I'll send it right back) I'll need to hold onto it while I use my new 140 ft-lb torque driver to re-tighten the pinion nut?

Should I replace the bearings in the axles?
thanks,
rich

 

[Superwrench]

Rich, I would bite the bullet. Unless someone replaced them, these are 50 year old bearings and seals on the pinion and axles. It is no fun pulling the rear end out after you are finished with your car. :hammer:

 

[drambuie]

One question i would ask myself before taking the rear end apart,How many miles are on it? Have you been driving the car with no problems and the rear end is operating normal with no noises or clunks? To be honest, I have had many cars in my life time and never had to rebuild a rear end They are soaked in 80-90 wt oil all the time and are very sturdy units.At most you may want to replace the front pinion bearing and seal and not have to crack open the the whole rear end. If you decide to, Have a manual and be sure to set the gear lash and end play properly, Setting pre-load on the bearings and make sure there is no binding between gears. and buy good bearings such as timkin, stay away from the cheap stuff made in china! I am 100% for working on my own cars and i always have and would not even think about letting someone else work on my british cars unless i had to, And it was more practical such as machining a head or engine boring ect.. For the heck of it i would get in touch with some healey shops like the the healey works" and ask them what a rebuild would cost before you get in over your head! Again i would ask myself, Do i really need to rebuild?????

 

[John_Progess]

I would at least remove the pumpkin and take a look at the wear marks on the gears, check out the bearings for any rough spots, check the splines and look for any metal in the lubricant. This will also give you a chance to check the wheel bearings and seals. If all is ok all you have lost is a couple of gaskets. It is also considerable easier to install the axle in the car with the pumpkin out if you don't have any help. I seem to always be alone when it is time to install something like this. Have a good day!

John

 

[Superwrench]

Rich, You talked about putting a fuel cell in so you could run some vintage races. That is a little different than taking Mom on a sunday drive for ice cream. You want it in good shape for either case, but have it checked out !

 

[richberman]

So do I need to pull the entire thing apart, just the pumpkin or drain oil for clues?

 

[HealeyRick]

If you're running it on the street and it's not noisy or leaking, I'd leave it alone. If you're going racing. I'd tear it own and check everything.

 

[Bob Claffie]

Rear end gears are virtually indestructible. Bearings not so much. Axles even more so. For the street I would change the fluid and inspect the seals. For racing the sky's the limit, what ever you can afford. Bob

 

[57_BN4]

I was surprised how little the Quaife ATB diff costs (relatively, there's a lot of machining and metal for your money!). If you are going racing and it is allowed, I'd definitely chuck one in.

On the left is what I found inside, the cross pin has sawn away quite a bit of the housing because it seized to the spider gear and began rotating in the housing. What better excuse for an upgrade.

Re the seals, they can be a bit of a challenge to replace. If replacing the front pinion seal, mark the shaft and nut, then torque up the nut to make sure it is tight, then remove/fit seal/re torque. If the marks are significantly differently positioned then I'd pull the head out to check the bearing preload as it looks like a sod of a job once in the car.

The side seals are behind the wheel hubs which are held in by big LH and RH-handed nuts which are eight sided so don't fit normal 6 sided sockets. They are quite a sod to remove, particularly if they have been done over with a cold chisel and bfh like mine were.

Both my wheel bearings were rumbly too so I elected to replace all the bearings. Easy to check them by putting a wheel on and spinning it.

Andy.

 

[richberman]

Do I need to pull the axles to remove the pumpkin? And if I replace the bearings and seals how do I check the preload?

 

[57_BN4]

Do I need to pull the axles to remove the pumpkin? And if I replace the bearings and seals how do I check the preload?

Yes, axles are easy to remove, just watch the oil that comes out doesn't get on the brakes.

If you are taking the head out, have an 'old school' diff rebuilder check it over as they will know the black art of making a diff reliable and quiet. The factory procedures are probably a bit complicated these days, a good rebuilder will have a feel for what is right and what isn't without all those specialised tools.

If you don't have the workshop manual and want to diy it, I have put a copy of the diff repair section here workshop manual diff section Note on page J6, the pinion nut torque reads like 1.680lb.in but is actually 1680 (=140 lb.ft) because the comma is not printed properly.

Andy.

 

[richberman]

Thanks for your reply. I did find an old schooler who will help with pulling the axles (I will have all replacement parts on hand 1st), pulling the pumpkin and checking it all out. I love this forum!!!