Worm Gear Cleanup

[Katahdin]

I've been cleaning up this worm gear with rust evaporator and bead blasting. Its still got some pitting but I'd like to put it back together and get some life out of it. What do you guys think?

 

[steelandcanvas]

If it is still within spec, polish it out with a wire-wheel and call it good.

 

[ODdave]

Sorry man, No-go. It rides on brass, Going to ruin the corresponding gear, Very high level of friction= gonna snap shear pins like crazy.

 

[Katahdin]

Hmm... I just remembered I have some lapping compound on hand, I could try to smooth out the pitting to lessen the friction.

I also have another housing on hand that came with this one, I guess I should crack that one open to take a look. I was hoping to avoid the extra work and keep it all together to use as a reference for the one I've got scattered across the work bench.

 

[spicergear]

If you can feel the pitting, so will the big bronze or brass bull gear. Honestly, the amount most people use their winch, if you can polish them...an averge person would be fine.

I still agree on it being a no-go...I wouldn't use it because I'd have a loose winch in a couple years.

 

[rchalmers3]

If that was the last pinion shaft on the planet, the decision to use it would be easier. But a call to George at White Owl will get you a new one in a few days.

That thing must of had some water in it awhile, eh?

Rick

 

[Katahdin]

Darn it, I was just on the phone with George this morning regarding a gaskets package that already shipped. Do you know if he has new gears or used take outs?

I do have a parts winch that came with this one, I just wasn't looking forward to cracking it open yet.

Re water, I guess, the drain plug on it was stripped even before the last owner got it three years ago. The plug was so tight it may never have been drained. It was pretty muddy in there but its all clean now.

 

[m16ty]

The main problem is the rough steel against brass. If the bull gear was steel I wouldn't be too worried about it.

 

[mobileauto2000]

If a replacement is available and inexpensive replace it.

If its costly I would put it in my big drill press and run some emery cloth on it and see how it came out.

 

[Katahdin]

Hmm... If I ignore the TM dis-assembly step-by-step instructions, I should be able to take the worm gear out of the parts winch without removing the drum, shouldn't I? At the very least I'll try to take the cover off it tonight to get a visual on the spare worm gear.

 

[spicergear]

YES you can. I did this a few months ago-

 

[Katahdin]

I took the side cover off the parts winch and the initial glimpse is encouraging. The metal is shiny and the bearings look a lot better than the other winch (I've ordered new bearings anyway). I can't spin the gears to inspect the rest if it because the brake is still on, and the drum lock handle is broken off, but with any luck I'll be able to put together a good assembly of parts this weekend and mount it on the truck.

 

[Katahdin]

Update to the thread.

I did end up using the second winch's worm gear. As you can see it was pretty nasty inside the second winch as well, but the worm gear cleaned up nicely. The gear grooves were in much better condition with only two small rust spots. I polished up the rust spots after letting the entire gear soak in rust evaporator.

The winch is about ready to put on the truck, it has all new bearings, gaskets, seals, and paint. It was pretty time consuming process but I learned a lot about how the winch operates and am glad I took the time to do it.

 

[gimpyrobb]

The sheer pin hole looks bigger in the "good" worm gear. Have you tested for any loose fit issues? It would be much easier to fix while not on the truck.

 

[Katahdin]

Good observation, shear pins I purchased recently from Memphis only fit the larger hole "good" gear, and that's a snug fit. The hole on the bead-blasted gear is either too small for the pins or the opening was marred. I have some shear pins incoming from Erik's in the next day or so that I'll test next.

 

[spicergear]

That band brake housing is another case of military 'water tight' as opposed to 'water proof.'

 

[gringeltaube]

.... shear pins .........only fit the larger hole "good" gear, and that's a snug fit.......

OEM pin diameter is 9/32" (7.14mm) and the hole size should be not more than 7.2mm for them to fit correctly.
But..... most often I have found those holes enlarged to 5/16"or even 8mm, possibly during rebuild, so custom-made pins with comparable strength had to be made to fit...

G.

 

[Katahdin]

That band brake housing is another case of military 'water tight' as opposed to 'water proof.'

That was the "dry-er" of the two brake housings. Here's the other one. After this experience, if you've never looked inside your winch I highly recommend it!

Gingeltaube- I'll get out the caliper tonight when I get home and take some measurements, thanks!

 

[gimpyrobb]

That band brake housing is another case of military 'water tight' as opposed to 'water proof.'

I know a guy that is so CRAZY, he removes his brake bands!










hehe

 

[Katahdin]

Alrighty, here are my measurements, keep in mind I'm using a cheap $20 digital caliper.

The "pot metal" shear pins from Memphis Equipment measure 7.80mm. These pins are very snug and appear to be the relative 'correct' size for both the PTO shaft and worm gear I have installed.

The aluminum pins from Erik's Surplus came today and measure 7.10mm. These seem to be a size too small.

The worm gear with the larger hole measures about 7.90mm +/- .05mm. There's some noticeable throat wear on one side of one of the holes.

The worm gear with the smaller holes measure about 6.9mm, if you look through the hole it does look a little "squished" on the other end. Neither shear pin will fit in this worm gear. I think lightly running a drill bit through the ends to removed the squished metal would quickly get the hole up to "spec.

The holes on the drive shaft are just a hair over 7.80mm so its a tight fit for the Memphis pins but you do not need any special tools to insert or remove the pin.

I'm thinking I'll move ahead with the worm gear I have installed and monitor for shear pin problems when I start to use it, that's my thought anyway.

Edit: Added picture