Rotax "C" Box Aft Large Gear Shaft Seal Leak

[LSaupe]

Hi All:

Noticed after my last two outings that I am getting a static leak on my upper shaft (large gear) aft seal (the shaft that sticks out of the case). Only leaks static after shut down and about 2 to 3 drops worth. A bit of a nuisance at this point.

Anyone experienced this before? Not sure if it is cold weather related or not.

To change this bugger (the seal), looks like the front half of the gear case needs to come off for sure. The bearing and seal being held in by a C clip.

Question though, have any of you changed this seal before? If so, can this be done without pulling the aft case half off the airplane (considerably more work)?

Hoping this is an easy/light pressure fit (can be moved with hand pressure or light pressure on a wood shaft). Hopefully a hydraulic press would not be required.

Anyone done seal change while on the bird?

[byteworks]

C&E Gearbox Maintenance article on California Power Systems' site, one of the many useful articles.
6 mm bolts and a rubber hammer.

[LSaupe]

Fabulous resource thanks for posting.

Actually my concern was removal of the aft prop shaft bearing and seal. The docs don't really seem address them directly (other inferring they will be pressed out - similar to the front bearing).

[Av8r_Sed]

I've replaced the rear seal on my C box. I removed the rear half of the gearbox to make it easier to press out the old seal and press in the new on my shop press. It's a lot of bolts, but not difficult in any way.

By the way, I was able to remove the front half of the box with the prop intact. That saved a lot of time.