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  • Winch Repair & Rebuild

    I'm getting ready to reassemble my winch after a complete teardown, and thought I would cover certain aspects that others might consider before trying to do it themselves. Mine was a complete piece of junk internally- it was run with 50% water and 50% 90 wt, so EVERYTHING had to be replaced, including the drum shaft. I had a new one machined out of 4140, and was about to pick it up, when the shop discovered the keyways were too shallow. A moron set it up in the Mill, and right before my eyes Instant Ruin happened! They're going to try again tomorrow...

  • #2
    After 3 tries, the machine shop finally came through on the shaft- double keyways aren't for idiots. I think gears might be a good place to start, as looking at them can tell you if you're going to double what you paid for the winch.

    Pic #1 shows my MU2 gear (left) alongside a brand new LU4 gear. Mine was worn out first on one side (pic #2), then reversed and worn out on the other (pic #3). The black coloration is not paint, but a sign of high-sulfur content oil- a big No-No with bronze gears. Notice how the wear is offset on pic #2 compared to pic #1. Presently, I don't have an explanation for that, unless the attempt to move the worm gear shaft forward 3/16" to get out of seal wear areas caused it.
    Attached Files

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    • #3
      Moving on, pic #4 compares the thickness of the old gear to that of the new-the last owner certainly got his money's worth! He also used a miracle lube composed of half 90 wt and half water- which did an excellent job corroding the worm gear (pic #5) and worm shaft bearings. If you're buying a winch, it would be a good idea to take the sideplate off and run your finger along the edge of the worm- if it's rough, it's junk. Compare pic #5 to the new worm in pic #6. I was fortunate enough to find new replacement gears at $170 ea, but Braden now wants ~$700 for the bronze bull gear, and ~$600 for the worm.
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      • #4
        Pic #7 shows how the worm had been pushed forward 3/16" to try get the seals into non-worn areas. The bottom gear is properly positioned- the cutouts in the shaft spacers are equally seated. The shaft spacers need to be measured for wear and replaced if out of spec- more on that later.

        Pic #8 shows the stepped keys (left side & center) made for the wider keyway of the LU4 gear, compare with the MU2 key in the left side. I decided to keep the original 5/64" keyway in the event I replace the LU4 gear with an MU2 gear in the future. The LU4 gear has a thinner web than the MU2, and the hub may need to be faced off a few thou to fit the MU2 housing, but otherwise it fits. Both my MU2 and LU4 gears were wider than factory spec, but the cap is meant to be single or double gasketted to allow the gear to fit with no endplay. My worn MU2 gear is 2 thou over spec, the LU4 is 4 thou over. The original gaskets are still available thru Braden dealers like Sam Winer (home of the precious metal gears) for ~$2 ea, or you can cut your own from 1/64" gasket paper like me.

        If you're in the market for a winch, you'll find they don't come for $50- $100 anymore. Everyone wants $500 plus for equipment that's likely worn out, so you'd be wise to add another $5-$600 for a complete rebuild. If you pay $1000 plus for a "rebuilt" unit, you'd be wise to insist on a money back guarantee if you're not satisfied with what you see after gear inspection- if they're junk, fresh paint, new bushings and brake bands don't matter much.
        Attached Files

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        • #5
          Great post! I was hoping to find something like this. I've a question for you though, and you can probably answer it. I believe the winch to be the stock MU2 (its on my 53 M37).

          When facing the winch on the truck there is a lever on the top left corner. It appears to have two detents cast into the housing that the spring loaded knob slips into. My lever is stuck in place - won't move or budge at all. It looks like its been "tapped" on before judging from the divit in the handle.
          Is this a common problem, and if so, what is the fix? Complete teardown involved in the repair or is it something external and simple? I've got the winch off the truck right now, but haven't opened it up yet...

          Thanks for the help Maine!

          Comment


          • #6
            Originally posted by MasterYota View Post
            Great post! I was hoping to find something like this. I've a question for you though, and you can probably answer it. I believe the winch to be the stock MU2 (its on my 53 M37).

            When facing the winch on the truck there is a lever on the top left corner. It appears to have two detents cast into the housing that the spring loaded knob slips into. My lever is stuck in place - won't move or budge at all. It looks like its been "tapped" on before judging from the divit in the handle.
            Is this a common problem, and if so, what is the fix? Complete teardown involved in the repair or is it something external and simple? I've got the winch off the truck right now, but haven't opened it up yet...

            Thanks for the help Maine!
            My LU-2 has a similar lever, frozen also. I believe it is there to release the spool from the drum allowing the cable to be unspooled quickly instead of having to "winch out" using the PTO. I was able to get mine unstuck, but not before the flimsey lever broke. The frozen part was a sliding collar on the drum accessable from the underside. Hope this helps.
            Bucky

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            • #7
              Master Yota- The MU2 clutch lever is on the right side of the winch, and has a spring-loaded knob that slides over a horizontal plate to engage a slot for either the "In" or "Out" position. The head of the bolt that holds the knob is used to drop into these slots. Have a pic of your winch?

              Comment


              • #8
                Sorry guys, must've had my designation wrong - according to the pics I've found on Google, its an LU4

                Comment


                • #9
                  More Winch Tech... rebuilding one of these is a good preview of coming attractions in Power Wagon rebuilding. The key is NOT opening more than ONE can of Whup A$$ at a time. One day I was feeling powerful peckish, and I opened 3 cans simutaneously- a million demons flew out and started putting the boots to me! I'll never try that again.

                  If you decide to replace the worm gear bearings, you'll need a good-sized puller or a press- pic #9 shows the MINIMUM size puller you'll need, and it wasn't easy- the bearings are on quite tight! Pic #10 shows how it's done with a press- lots faster. The split bearing puller plate was convenient, but you could use press bars against the bearing if you're careful. When you re-intall the bearings, you'll have to make a spacer about the same OD as the worm gear spacer to avoid damaging the bearing- you can't press against the outside cage. I had a new worm gear, shaft, and spacers, so I used one of the old spacers for this job. Be sure to install the cutout side of the spacers against the shaft key, and the bearing with the small end facing out.
                  Attached Files

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                  • #10
                    If you have to install a new Bull gear, you should measure the distance from the shaft end to the gear hub- mine was 1 19/32". The LU-4 gear was a couple thou thicker at the hub than my MU-2 gear. What you have to watch is the distance between the gear hub and the dog key spacer- pic #11 shows there's almost NO slop between the key, spacer, and gear housing. The gear is fitted to turn freely with NO endplay against the cap by means of spacer gaskets. Pic #12 shows one cut from .028" gasket paper on the left, and VPW's .013" gasket on the right- you have to trim the outside. Pic # 13 shows a hole punch turned from 1/2" rod with a 3/8" hole in the center. Press down and rotate- perfect bolt holes every time. Cut the inside hole to the OUTSIDE of your tracing line if you're using a cap gasket as a form- better slightly too large than a little too small! I ended up with a 3-gasket pack of (2) .028" and (1) .013" to get the proper clearance. I also had to file off some high spots on the hub- you'll know if the gear sticks in certain places during a full rotation. Use an ink marker to coat the hub face, any high spot will come up shiny after you rotate the gear. You will be assembling and disassembling the gearcase MANY times during fitup, so learn to get good at it.
                    Attached Files

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                    • #11
                      Originally posted by MasterYota View Post
                      Great post! I was hoping to find something like this. I've a question for you though, and you can probably answer it. I believe the winch to be the stock MU2 (its on my 53 M37).

                      When facing the winch on the truck there is a lever on the top left corner. It appears to have two detents cast into the housing that the spring loaded knob slips into. My lever is stuck in place - won't move or budge at all. It looks like its been "tapped" on before judging from the divit in the handle.
                      Is this a common problem, and if so, what is the fix? Complete teardown involved in the repair or is it something external and simple? I've got the winch off the truck right now, but haven't opened it up yet...

                      Thanks for the help Maine!
                      What you have going on is a common problem, steel shaft in an aluminum housing bore. Corrosion common to aluminum when mated with a dissimilar metal. You will need to remove the clutch end housing, remove the shift fork set screw, remove the plug on the bottom side of the housing that is pressed into the shaft bore, apply penetrating oil liberally, and persuade the shaft out by whatever means you have available.

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                      • #12
                        These were my thoughts exactly. Any particular worries about this operation, or is it pretty straight forward?

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                        • #13
                          Soldiering on thru my MU-2 mess, I found the winch drum shaft to be worn in the bushing areas and pitted in the case bushing area by water infiltration. I had a local machine shop make a new shaft out of 4140, as there don't seem to be any non-rusted OEM shafts available. You want a good grade of 1.75" shaft stock used for this, "ground, polished, and straightened". The placement of the keyways is absolutely critical- which is why the shop spent $150 in material and who knows what in labor making it 3 times- I paid $147 for the original Quote. The keys are a non-standard size in depth- make sure the shop understands that, bring in your old shaft and keys so there's NO misunderstandings. The dog keys can't be real sloppy either- I ended up having my keyway made "tight", then I surface ground the keys to fit snug- but loose enough to remove with pliers. Pic #14 shows the new shaft alongside the original. Pic #15 & 16 shows the spacing of the bushings, gear, and dog- again note the "zero tolerance" fit of the spacer that separates the dog keys from the winch housing. When you press on your new gear, you need to have a good idea when to stop. The dog is countersunk to almost the depth of the spacer in order to disengage from the drum, and the dog keys riding against the spacer prevent side thrust against the gear & sideplate, so it's wise to check the original spacer for wear. If the original is too thin, try substituting the other spacer from the drum end of the dog. The next topic will be bushings- the most labor-intensive part of the entire project.
                          Attached Files

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                          • #14
                            Here we go with bushing removal, fitting, and modification. Take whatever time is necessary to get this right, because it will make a big difference in gear/shaft life. The silver urethane paint job on the gearcase interior is not absolutely necessary, but it makes cleanouts much easier by showing up chips and dirt. Pic #17 shows the two bushing types used, the gearcase bushings are slotted, the leg bushing is not. My winch had plain bushings in the gearcase, which meant somebody had replaced them. The slot is aligned with cutouts in the cap and case at the top of the shaft (pic #18 & 19). The cutouts collect gear oil that falls off the bull gear and feed it to the slot to distribute across the shaft.
                            Attached Files

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                            • #15
                              I gave this idea some help with heavy gear oil by opening up the slot end of the bushing (pic #20), as the stock slot opening is VERY small. You definitely want to check that the open slot end faces the inside of the gearcase BEFORE you press the bushing in, ESPECIALLY on the cap, as you have to destroy the bushing in order to remove it (pic #21). I ended up having to carefully slot the cap bushing with an air grinder after trying several other methods. The case bushing and the leg bushing can be pressed out with a suitable adapter, which needs to be slightly under 2" OD. The Leg bushing will have to be drilled with a grease hole that has to center under the grease channel (pic #21)- this channel is not centered in the leg casting, so you also have to pay attention bushing orientation when you install it. The channel carries grease all around the bushing, so the hole need not be under the zerk.
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