Rear axle - small leak .....?

My major winter project this year was removing and restoring everything from the drive shaft back to the brake drums. This included removal of rear axle, brakes, suspension, shocks, etc. t

Re-assembly went smoothly, including setting the wheel bearing clearance to within spec. New gaskets and o-rings were used throughout. When complete, I over-filled the differential by about 500 ml, allowing the excess to drain away through the upper-most port in the diff.

A few weeks later, I noticed a very small amount of oily liquid running down the backplate. See picture attached. Total volume maybe 5 ml. Pulling the drum revealed a completely dry and clean wheel hub and brake assembly - no oil at all. If this means that the hub is not leaking into the brake area, could the small amount of oil be from initially over-filling the differential? I checked the fluid level in the differential and it is still fully topped up.

thanks
steve

Wipe it up see if it does it again. Try to identify a track from you top vent on the diff to where it dripped. Also if it is really overfilled, the oil expands with running and heat. Make sure it is filled just to the bottom of the fill plug.

Are you sure it's not brake fluid?

The pictures both looked identical.

steveg said:

The pictures both looked identical.

Click to expand...

They are; they have the same filename.

Are you sure it's not brake fluid?

Click to expand...

To find out if it's gear oil or brake fluid, smell it, although brake fluid would more likely be on the outboard side of the backing plate.

If it's gear oil, you may have used the too-thick cardboard gaskets which prevent the bearing from being properly clamped. If the bearing spins, it can destroy the seal, causing a gear-oil leak.
For more info, see:
https://www.pbase.com/stevegerow/healey_rear_bearing

vette said:

Wipe it up see if it does it again. Try to identify a track from you top vent on the diff to where it dripped. Also if it is really overfilled, the oil expands with running and heat. Make sure it is filled just to the bottom of the fill plug.

Click to expand...

Thanks for the suggestion. There is no fluid track from the vent.

I cleaned it up thoroughly and shot another 100 ml of oil in. That was 6 hours ago and most of it ran back out from the filler plug over the last 4 hours. So far, no oil is appearing at the backplate...

Thanks Steve. The gaskets came from Ahead4Healeys and they are quite thick, at 0.014”.

the car has not yet been driven, so the bearing really hasn’t been spun. The area outboard of the backplate is completely dry....