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Ibreakstuff 12-27-2007 11:47 PM

26 Attachment(s)
This how-to is for an aggressive chassis Polaris (98 XCR 700). Most are close to the same, major differences in sleds with mechanical reverse.

Prep work:
1. First, drain your chaincase oil. There's a drain plug on the bottom, accessible outside the belly pan on the bottom. If yours doesn't have one just use a syphon through the dipstick hole and get as much as you can out.
2. If you have liquid cooled brakes, you're going to need to drain about half of your coolant out as well.
3. Loosen your track tension. Makes getting the actual chaincase off much easier.

Next, remove the pipe or pipes:

Attachment 603

I prefer vise grips, they keep the springs from flying all over:

Attachment 604

I already did, but remove the 4 screws that hold the chaincase cover on. This is what the inside looks like:

Attachment 607
Attachment 608

Inside you have a top gear, lower gear, chain, and tensioner (seen at right). Now you want to loosen the jam nut on the tensioner. It's a 1/2inch.

Attachment 609

Then loosen the actual bolt. It may just be finger tight or might require a socket. After you loosen it all the way your tensioner is just kind of flopping there and you can remove it.

Attachment 610
Attachment 611

Now you need to remove the gears. The top is held in place with a castelated but and a cotter pin. I bend the cotter pin with a flat-bladed screwdriver until I can grab it with channel locks or pliars:

Attachment 612
Attachment 613

Then you can remove the bottom bolt and washer. 1/2inch I believe:

Attachment 611

Then it's just a matter of pulling the gears off. Since the chain won't let you wiggle them you need to pull them both off at the same time.

Attachment 614
Attachment 615

Now it's time to get to the brakes so you can get the caliper off. I had to remove the little toolbox thing. Mine was held on by about 400 Torx screws.

Attachment 616

Remove the clamps that hold the brake cooling lines on (if applicable).
This bracket is held on by the same bolts that hold the caliper in:

Attachment 617

Now it's just a matter of prying the caliper off the rotor and twisting it out of the way.

Attachment 618

Now it should look something like this:

Attachment 630

Start getting the actual chaincase bolts off. They are all carriage bolts and are accessible with your hand in the tunnel. There are 4 total.

Attachment 620

After you have all 4 off, it's a LOT of wiggling, prying, moving, knuckle-busting to get it off. Eventually you will be looking at this:

Attachment 621
Attachment 622
Attachment 623

Congratulations. Your chaincase is out of your sled. Now it's time to do what we dissasembled it for.

This is a very blurry picture of the snap-ring that holds the bearing in.

Attachment 624

Use snap-pliers to get it off. No, don't use a pair of needlenose you've ground the tips of. At least get cheapo tools from Harbor Freight!

Attachment 625

After you have the snapring out, flip it over. I use a crappy "made in tawain" socket to pound the old bearings out. You want it bigger than the OD of the bearing but smaller than the seal.

Attachment 626

Flip the chaincase over, and use either a bigger socket or a punch to get the seal out.

Attachment 627
Attachment 628

Tap the new bearing in, same for the new seal. Repeat for other side (bottom or top depending on which one you started with).

Make sure the place where the seal rides is clean and not "buggered" up. If it is it will chew up the new seal really quick.

Attachment 629

Reassembly is the reverse of dissasembly. Clean and inspect the chain/gears/splines when reinstalling. I use threadlock on the nut/bolt that holds the gears on. Take the cover seal off and clean it. Also use a dab of RTV on the top where the ends meet to help seal it. Clean the dipstick as well before reinserting. CLEAN THE BRAKE ROTOR with brake cleaner!

PolarisRich 12-28-2007 10:24 AM

Wow good job Bryan!!!
Almost as nice as the Studding your sled How-to. lol
Very informative and great pic's to help with the whole visual aspect of doing the job.
We need more How-to's like this!

Rubi 12-28-2007 01:20 PM

That's a real nice tutorial you posted there. That would have been very helpful on a recent project of mine. Your application must be different than mine though, since I didn't see mention of a 6 Lb. maul, or a cutoff wheel in your post. These tools were an integral part of my chaincase project. I'd like to disagree with one thing you posted: I don't think buying a Chinese snap ring pliers is the way to go, since it probably won't last through this whole project. Get a decent American one, so you can use it next time too.

PolarisRich 12-28-2007 02:05 PM

Hey Rubi
I don't think Bryan is talking about Chinese snap ring pliers but you are right when you say that you should buy a good set of snap ring plier's. The cheep ones tend to bend and break very easily and can damage the part you are working on or send a ring flying to god know's were.
I think he is talking about a Chinese socket. Cheep disposable crap socket so that you don't damage your good Snap On one's.

Ibreakstuff 12-28-2007 02:20 PM

Yes, made in taiwan socket, but those snap-ring pliers that I used are from Harbor Freight, a half-step above taiwan.

Rubi if your bearing gets destroyed and you continue to ride on it, it will basically weld itself to the jack/driveshaft. I drove 5 hours on a bad wheel bearing in my CJ-7 and I had to cut the inner race off with a dremel into 1/2 inch by 1/2 inch pieces and chiselthem off.

Rubi 12-28-2007 04:53 PM

^^^^That explains my difficulties. Mookie's brother, Gerbil, rode that sled several miles last year after the bearings siezed.

Last time I looked in Harbor Freight I don't think I saw anything that wasn't made in China. I just don't like giving my money to the government of Red China. I hate giving money to OUR government, why would I want to contribute to theirs.

slednecks1996 11-23-2010 09:27 PM

hey guy's, this going to sound stuipid but I just started sledding last year so I don't know much .... But willl your chaincase seal dry up and suck up water? my chain case oil is creamy and a guy said you need a chain case seal or something please help!?!!

Ultra Willie 11-23-2010 09:42 PM


Originally Posted by slednecks1996 (Post 106885)
hey guy's, this going to sound stuipid but I just started sledding last year so I don't know much .... But willl your chaincase seal dry up and suck up water? my chain case oil is creamy and a guy said you need a chain case seal or something please help!?!!

First of all WELCOME to the site. If you have contamination (like water) I see where Ibreakstuff as the step by step for doing just what your asking. Oh by the way Bry that is a real good explanation, think you could put that in a power point presentation. Hahahahaha

Madcow 11-24-2010 08:32 AM

takes 5 minutes to take a bearing off with a torch!! i learned long ago that bearings are cheap and time is not.

good job bryan!

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