I don't mean the motor part, just the mast (is that what they call it?) The top part of mine rusted out after maybe 6 months. I tried WD-40 but no luck. The service place charges around $55 to replace it but I did see the mast on e-bay for $20.

 

Steve:
Yikes... Perhaps you had a crappy part on your hands to begin with. My mast was replaced by the PO years ago and is still operating perfectly. The home remedy I heard for oiling them is, in fact, to use the lightest coat of transmission fluid.

Scott

 

Yikes is right, that's a new one to me. I probably wipe mine with any lubricant in my hand at the time about once a month or so. No issues so far.

 

The WD-40 kicked in after an hour or so and now it works again.

 

There's a possibility that your aerial drain is clogged up, leading to the housing being full of water, hence the rusting.