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Posted by David Sherman [24.32.202.83] on Thursday, February 18, 2010 at 20:31:19 :
In Reply to: In my defense... posted by Jon Kelly [98.197.106.42] on Thursday, February 18, 2010 at 19:02:56 :
I didn't mean to put you on the defensive. I was just disappointed that I couldn't find any MU2 info there. I just got done overhauling my very worn out MU2. They are extremely simple and easy to work on. The problem is parts are expensive. The main challenge is deciding what really needs to be replaced, what can be repaired, and what can be left as is. I made lots of compromises, mostly based on the fact that I wanted to be able to use it for unsticking my truck, but it would not have to win any shows and it would not have to stand up to daily hard use. I think I probably have about $250 into mine, but it would be easy to drop a grand on one if trying to do everything perfect and not shopping around much. For what it's worth, here's a summary of what I did, and what I didn't do:
Tore it all apart and cleaned everything out with gasoline. Painted the inside of the castings (not necessary, but easy, and keeps oil from seeping through any porosities and makes it easier to clean out again later). Bought generic hard bronze bushings at a bearing house and cut them to length. Standard lengths left one of them 1/8" too short, so used that in the housing end cap where it doesn't have much load. That was cheaper than buying the "proper" ones. The originals were oillite so I may have made a mistake going to hard bronze, but thought they'd hold up better.
All my bearings were shot so I replaced them, but saved $50 by getting the cones off ebay rather than from the bearing house. Also found speeedi-sleeves cheaply on ebay vs $25 apiece at the bearing house, and sleeved the screw gear shaft, which was badly pitted. Replaced the seals, of course.
Replaced the big gear with one I got a couple years ago off ebay for $45. It is made of powdered iron, rather than brass, but is an exact replacement, and $250 cheaper than the brass one. Don't know if they're still available. Left the screw gear in even though it was badly rust-pitted and will probably wear on the big gear. The pits are mostly on parts that don't touch the big gear, and a replacement screw gear was too expensive. Had to replace the drum shaft because it was ground down too small at both ends. The one I got from VPW was $75 and badly rusted, including in the bearing surfaces, but they said it was the best they had. Electrolytically de-rusted it, and then put it in the lathe at high speed and polished it the best I could with fine emery cloth. If these are the best NOS drum shafts left in the country, it's time for someone with a milling machine to start reproducing them. Bought one new sliding shaft key from VPW, but re-used the rest of my old ones which were damaged but looked usable. Mine had no shifter/brake, so I had to buy that assembly from VPW, but I made the mounting bracket for it, the bracket that the spring drops into, and used a bolt for the brake shoe pin.
I don't quite have it back on the truck yet, but I think it will be good enough for what this truck will be used for for the the rest of its life and mine. The whole thing was definitely an exercise in deciding how good was good enough, plus some money-saving shopping.
There is a surplus outfit selling new Chinese copies of a very similar winch, but designed for flat base mounting rather than angled mounting on the font bumper. If your winch is in real bad shape, it might be cheaper to buy one of those and use it for a parts kit than to rebuild yours with individual parts. I think they were $750 plus $100 freight. You'd basically be transplanting all the innards of the new winch into your old castings. Since the castings are undoubtedly the worst part of the Chinese repro, you'd end up with a real good winch.
As far as tricks to disassembling and assembling, the only things that were slightly non-obvious were getting the bushing out of the housing end cap (had to cut it with a cape chisel and break out the pieces), getting the big gear off of the drum shaft while it was in the housing (it was tight and needed some pounding), and setting up the worm shaft gears for proper pre-load (buy two of each thickness of gaskets from VPW and try them until a thinner stack makes it too tight. Test without the big gear in place, and without the shaft drag brake installed, so that you can easily turn the input shaft by hand. If it binds at all, add more gaskets.
Also, when I put it together with the gear housing end cover gasket from VPW, the drum shaft bound up and was too tight. Their gasket looked thinner than what I remembered the original being, but I'm not sure about that. Perhaps the keyways were cut slightly differently in the "new" drum shaft or my new big gear was slightly thicker. Anyway, cut my own gasket out of thicker gasket paper and it provided just the right clearance.
Good luck with your rebuilt. It's really fairly simple and obvious once you get into it, but could get expensive fast if you don't know when to stop.
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