Hi. So I have a factory mounted Mayflower Automotive MK-III P.T.O. drum winch on my Land Rover 109 Series III 1977.
I tried to use the winch a while back but it didn’t move, I checked the PTO under the lid in the center seat and noticed that the shear pin was replaced by a broken nail. I put in a M6 bolt instead of a shear pin (steel grade 8.8) and tried to turn the winch.

At first, the bolt snapped immediately, so I replaced it with a new bolt, this time gently releasing the clutch, tried to go first gear, then reverse, then first, then reverse and soon the drum started to unroll the winch cable. I then went in to first gear again and the drum started to take up the winch.

I went out of the car with the winch turning, checked the drive shaft and it was spinning nice without any strange sounds. I tried to disengage the winch clutch (big lever), then engaged the winch clutch, just to test the functions. It worked properly, the drum stopped and started as it should, no strange sounds or vibrations but suddenly the shear pin (M6 bolt) snapped once more.
I replaced it, and went for another try, snapped again. And again, and again…

The winch seems to be completely stuck, I can’t move the drive shaft nor the worm gear at all. Whats my options here? Disassemble? Go for a M6 12.9 steel grade quality to try to force it loose?
When replacing the oil in the gear housing it first ran out like 2-3 dl of water… It’s now rinsed with diesel and filled with gear oil. Could the water have destroyed some bearing?

Any thoughts?

Short video showing the movement of the drum

 

I hate to say it, but I would pull that thing off and totally disassemble it. Clean it all up, lube/check everything and then build it back up. Winches are awesome. Awesome at pulling heavy vehicles out of sticky conditions. Awesome at totally destroying equipment. Awesome at shearing body parts off. That kind of binding is not a natural / designed force and if it is shearing off bolts like that, I would be highly nervous of working around it.

It absolutely sucks, but unless you get lucky and someone has already done the above on this forum - it's up to you to contribute to the tribal knowledge!

Good luck and take pics.

 

Yeah I guess you are right about it needing a disassemble.
I'll have to do it during the winter time, this car is only used during summer and I don't want to take it into the garage now.

I'll update the thread with photos and video when I get to work in a few months. Hopefully it's just a collapsed bearing.

Thank you!