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1996 Skandic WT 500F - 10k Maintenance

3K views 33 replies 12 participants last post by  LabradorBoy 
#1 ·
Picked up this old girl late last Fall to use as a groomer donkey. Great shape, but it was making funny sounds in the drivetrain and finally at the end of the season it started leaking gearbox oil. I feared that the gearbox had failed and she was headed for the scrap heap.

Tore into it yesterday and removed the rear skid, driveaxle and gearbox... Found the grinding sound, driveaxle brg on the throttle side was gone gone and seized in the holder.

Got it on the bench and it appears that the shaft was spinning inside the inner race and the shaft is worn down: should be 25mm, is more like 23mm at shoulder and 21mm at the end of the shaft. Crap. There are no machine shops here that can practically build up the shaft again, that would require a significant investment.

Not sure what my options are but I mocked things up with electrical tape to center the brg half decent tonight and I'm contemplating welding the brg on, being careful with heat. Hardest part would be that the brg has to go on the shaft after it's in the chassis (because of brg holder assembly sequence) so I can't weld it on the bench. Not sure what I'm going to do there.

Welding is semi-permanent but I'm not sure what else I can do to get this thing back moving without a significant investment. Any ideas?













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#2 ·
Have the shaft turned down to a new OD and a tight fitting bushing (sleeve) turned with the new bearing ID as the bushing OD. Use bearing lock adhesive when driving the bushing onto the shaft if needed. Seems like the shaft is worn enough that the custom bushing would have some appreciable wall thickness. I would expect a capable machine shop could do this. It comes back to you ready to install. Not sure if the cost is within your budget goal, but it would be a permanent fix.
 
#8 ·
Yes that's exactly how I would do it were this my primary sled. This is sled # 4 or 5 and I use it primarily to groom some local trails and the sliding hill for the kids so I cannot spend a ton of cash on this one. It will have to be a "red around the neck area" fix until I can find a replacement used drive axle somewhere for cheaps. These projects are fun, and we sometimes surprise ourselves with how long the "temporary fix" lasts.
 
#3 ·
Picked up this old girl late last Fall to use as a groomer donkey. Great shape, but it was making funny sounds in the drivetrain and finally at the end of the season it started leaking gearbox oil. I feared that the gearbox had failed and she was headed for the scrap heap.

Tore into it yesterday and removed the rear skid, driveaxle and gearbox... Found the grinding sound, driveaxle brg on the throttle side was gone gone and seized in the holder.

Got it on the bench and it appears that the shaft was spinning inside the inner race and the shaft is worn down: should be 25mm, is more like 23mm at shoulder and 21mm at the end of the shaft. Crap. There are no machine shops here that can practically build up the shaft again, that would require a significant investment.

Not sure what my options are but I mocked things up with electrical tape to center the brg half decent tonight and I'm contemplating welding the brg on, being careful with heat. Hardest part would be that the brg has to go on the shaft after it's in the chassis (because of brg holder assembly sequence) so I can't weld it on the bench. Not sure what I'm going to do there.

Welding is semi-permanent but I'm not sure what else I can do to get this thing back moving without a significant investment. Any ideas?

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Did that before, the tape is just to center the bearing on the shaft, with everything locked in place it should be fine, personally i would have split a piece of copper tubing and pounded it in there, probably not worn enough for that though
 
#5 ·
If this machine will not work hard or go on long / far rides, the tape fix should be fine.
But definitely, turning the shaft + sleeve would be a much better / permanent fix.
Too bad you can't find a used shaft in a scrap yard.
That guy doing gearbox rebuilt maybe would know where to find one.
 
#12 ·
Yes JB weld would work fine, the trick is to get the bearing centered on the shaft, what i have done in some cases is to punch the shaft with a center punch a series of indentations alll around the shaft full width of the bearing, the swelling around punch holes holds the bearing snug & center, coat in JB weld and drive the bearing on, but this would not work if the shaft is worn too much
 
#14 ·
Such a smart, practical way to do it. Shaft is too far gone for the dimpling to make up the difference, from what I can see. With the weld method the inside edge will be semi-permanently on the drive axle. I don't like that idea as it will be very difficult to get the brg off if it has to be changed again in future. I doubt that will ever really be my issue, but I still don't like it. Easy to grind the outer welds off at the end of the shaft, but those inners inside the tunnel will be misery to grind/cut/punch off.

How does JB weld respond to sanding? Starting to wonder if I couldn't build up the shaft a bit with it and then adjust manually with sandpaper but that might take a lot of effort and there's no way of knowing if your work is centered. At least with the tape it's a gradual build up on all sides of the shaft.

Still thinking. I have the weekend to figure this out.

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#15 ·
If you don't have access to a metal lathe, maybe one for wood would be good enough to spin the shaft to make it nice and round with a file.
Then maybe you could remove enough material to fit a piece of sliced thin or thick copper pipe to act as a sleeve.
Glue it all together with JBweld if you have to and you're in business.
Keep us posted on what will be your solution.
 
#18 ·
I'm guessing it's the same shaft as the early 2000's....only difference is i think is the 1996 had a smaller end (same size spline ) that goes into the transmission...a picture of the spline end would confirm if the shaft was upgraded to the bigger one, if so i may have 1 or 2 and could find a half dozen or so in the local scrap yard...then there's the logistic issue to get it up there low cost?
 
#19 ·
The seal in the gearbox was 26/52/8 so the shaft OD should be 26mm at the gearbox spline end. I highly doubt that the driveaxle was upgraded on this one, it is stocker than stock and in a fellows shed for years. See if you can find one, I'll get you a pic when I'm back after the weekend. Replacement would be ideal over any machining, there should be dozens of these scrapped out there.
 
#21 ·
Any way to weld a washer to the outside of the inner race such that when you put that bolt into the end of the shaft, it centers the bearing relative to the shaft. A couple holes drilled into the washer should allow enough to tack to the race?

(I'm not familiar with the assembly, so there may not be any room for an additional washer)

Otherwise, I'd go with your original plan of electric tape and trying to tack it to the shaft, or press off the drivers and take RR up on his offer ;)

Edit: Looks like we were typing at the same time, and you may have it figured out
 
#24 ·
Not a bad solution at all, but still a struggle to ensure that the thing is true. While gear reduced twice (clutches, then gearbox) that sucker still turns at 2000+ rpm when at 60-70km/h.

A couple of shafts have come out of the wood work and I'm going to try a local one tonight to see if that fits. Not cheap, but cheaper and much faster than some of the solutions I have possible. See how things go tonight.
 
#29 · (Edited)
No great pics to share but this thing went back together quite well yesterday. Biggest pain was introducing the larger drive axle to this chassis; the outer drivers have "fingers in" where the older ones have "fingers out" which allows more room between the outer drivers and the mounting bolts for the gearbox and driveaxle brg. Had to do a lot of fooling around to move the axle left/right for clearance on reassembly.

Aftermarket drive axle brg also had a shorter inner sleeve so I had to make up a spacer to get to the end of the shaft so the end washer could hold things together. Happily 600mL of 75w140 did not spill out into the floor and I drove her out of the bay to her storage position [emoji16]

On to the next one!

Edit: I also want to add that because I didn't have enough time to totally scrap the rear skid and maintain each idler brg, I used a grease needle to at least firm up each wheel. Using a tiny flat screwdriver I was able to lift the inner edge of the seal ever so slightly, insert the needle and give it a few squirts of fresh grease at 0* and 180*, then pushed the seal back down flat to seat it properly. I was impressed at how fast and how effective it was and would do it again on a quick turnaround project without hesitation. I admit that I had to hone my skills with the needle on the bench to get used to what it can take without folding and how the brg "feels" so that I could get the needle in deep enough to make a big impact. Glad I took the time to do that and recommend it to others, major time saver.

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#30 ·
One or more piece of copper pipe split lengthwise to center fill the gap. A brass bushing or a piece from a brass curtain rod, or several flat carriage washers stacked together (you drill the holes in the washers to fit your 23mm. There are so many different sizes of carriage washers than you could probably find one size that would fit. And if not perfect a few wrappings of electrical or gorilla tape will suffice.
 
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