Was out for a ride yesterday when my chain starting ratcheting as it was too loose. Got home and ripped everything apart and found almost no oil in the case. Chain is stretched but gears look ok. I'm thinking the bearings are probably near death as they ran without oil for sometime, they still look ok and haven't started to come apart. I'm wondering what the procedure is to replace upper and lower chaincase bearing. Does the track need to come out?
replacing chaincase bearings
- Thread starter MustangDoug
- Start date
How much oil was in there? Was the lower sprocket touching it?
Track stays in, release tension on it. You might need to pull the rear idler axle and wheels to get enough slack. unbolt speedo drive housing and remove bearing retainer, (bearing is pressed on shaft). slide drive shaft over until you have clearance for the chaincase to come out. The track has to be all the up and forward in the tunnel to let the shaft slide over.
chaincase
No the oil was not even touching the bottom sprocket, the chain is in rough shape, I'm thinking I should do chain and sprockets together even though the sprockets look ok? Do these bearings rely on oil splash for lube? They look ok too but who knows for how long. My cover did not have the update done to it even though Polaris insisted all updates were done.
No the oil was not even touching the bottom sprocket, the chain is in rough shape, I'm thinking I should do chain and sprockets together even though the sprockets look ok? Do these bearings rely on oil splash for lube? They look ok too but who knows for how long. My cover did not have the update done to it even though Polaris insisted all updates were done.
Greetings MustangDoug,
Good tips from the other sledheads.
Offered for your consideration -
I learned this the hard way, if this ever happens again as soon as you hear your chain jump the teeth on your sprockets, immediately adjust the slack out of your chain. Loosen your back-up nut and twist in the adjuster bolt by hand until the chain is tight then back out 1/8 turn + - set back-up nut. I've used two stroke oil in the chain case to limp back to the truck, I realize the two stroke oil is not the best however it is better than nothing.
Some bearings used in chain cases are sealed, minimizing the amount of metal that could slip through and cause bearing failure...I would recommend replacing your bearings. You successfully limped your sled back to your truck, nice job! More than one sledhead has had the chain come apart and taken out their chain case housing.
In the States I would take my bearings to a Kaman bearing vendor you can purchase the bearings cheaper than going to your local Snowmobile dealer.
Check your seals behind your bearings for nicks or indication of heat.
You should be able to gently drive your bearings out with a punch & hammer from the back side of the chain case.
Going back together dry fit your bearings find a 3/4 drive socket...1 3/8+- that can be used to gently seat the bearing in the chain case up to your seal, a piece of wood will work as well. Before you use the socket trick I like to put the bearings in the freezer overnight. Lay your clean chain case assembly out with support tools and pre-lube the bearing housing. I use a small propane bottle torch and apply heat to the entire chain case housing until the chain case is warm to the touch but no flame directly on the seals. Between freezing your bearings and applying heat to the chain case housing the bearing will slide into the chain case easier but you will more than likely need to provide a few love taps with a hammer and socket. Pay special attention to the placement of your bearing to the chain case keeping everything square.
Good luck with your project.
Craig.
Good tips from the other sledheads.
Offered for your consideration -
I learned this the hard way, if this ever happens again as soon as you hear your chain jump the teeth on your sprockets, immediately adjust the slack out of your chain. Loosen your back-up nut and twist in the adjuster bolt by hand until the chain is tight then back out 1/8 turn + - set back-up nut. I've used two stroke oil in the chain case to limp back to the truck, I realize the two stroke oil is not the best however it is better than nothing.
Some bearings used in chain cases are sealed, minimizing the amount of metal that could slip through and cause bearing failure...I would recommend replacing your bearings. You successfully limped your sled back to your truck, nice job! More than one sledhead has had the chain come apart and taken out their chain case housing.
In the States I would take my bearings to a Kaman bearing vendor you can purchase the bearings cheaper than going to your local Snowmobile dealer.
Check your seals behind your bearings for nicks or indication of heat.
You should be able to gently drive your bearings out with a punch & hammer from the back side of the chain case.
Going back together dry fit your bearings find a 3/4 drive socket...1 3/8+- that can be used to gently seat the bearing in the chain case up to your seal, a piece of wood will work as well. Before you use the socket trick I like to put the bearings in the freezer overnight. Lay your clean chain case assembly out with support tools and pre-lube the bearing housing. I use a small propane bottle torch and apply heat to the entire chain case housing until the chain case is warm to the touch but no flame directly on the seals. Between freezing your bearings and applying heat to the chain case housing the bearing will slide into the chain case easier but you will more than likely need to provide a few love taps with a hammer and socket. Pay special attention to the placement of your bearing to the chain case keeping everything square.
Good luck with your project.
Craig.
I don't have the last word on this, but I replaced both the gears and the chain when my case ran dry a few years ago. The gears are case hardened so you don't know where that hardness is thin now, or worn through. I would certainly replace the gears if you see signs that they got hot (discoloration). Do a search on gears to find the best ratio if you buy a new set.
gears
I have the 19/42 gearset so the previous owner must of changed the ratio. I was going to tension the chain some during the ride but it looked almost impossible to get a wrench in there, that big suitcase muffler Polaris puts on there is HUGE. I wasn't far from home and there were no steep hills so I limped it home with only minimal amounts of ratcheting. I think it has been dry for awhile though as there were no signs of oil on the chain or gears. I normally check chaincase oil from time to time on my sleds but this one was bought used from a Polaris dealer and I assumed (stupidly) that everything would be good to go. I haven't put many miles on since purchase. Thanks a lot for the info, I already have the new bearings, they are a 6205, very common, and I always buy my bearings from Kaman or BC bearing. The mark-up at the dealer is outrageous.
I have the 19/42 gearset so the previous owner must of changed the ratio. I was going to tension the chain some during the ride but it looked almost impossible to get a wrench in there, that big suitcase muffler Polaris puts on there is HUGE. I wasn't far from home and there were no steep hills so I limped it home with only minimal amounts of ratcheting. I think it has been dry for awhile though as there were no signs of oil on the chain or gears. I normally check chaincase oil from time to time on my sleds but this one was bought used from a Polaris dealer and I assumed (stupidly) that everything would be good to go. I haven't put many miles on since purchase. Thanks a lot for the info, I already have the new bearings, they are a 6205, very common, and I always buy my bearings from Kaman or BC bearing. The mark-up at the dealer is outrageous.
Chaincase update bracket needed
Do any of you guys that upgraded your chaincase covers have the support bracket and the two longer bolts that were part of the recall for the 2005 900 RMK for oil leakage? I need one, I also need a 92 pin chain if anyone has a good used one.
Do any of you guys that upgraded your chaincase covers have the support bracket and the two longer bolts that were part of the recall for the 2005 900 RMK for oil leakage? I need one, I also need a 92 pin chain if anyone has a good used one.
Dude!!
If you notice leaking fluids.. check where they are coming from..
You are supposed to check your chaincase oil level (sightglass) every ride.
Use a good quality synthetic chain oil like Polaris, amsoil, Redline.
at this point... pull the entire chaincase, install new upper and lower seals (Polaris has the best price). Install new uppper and lower bearings, install a new plastic cover and use the updat bracket plus insulation OR .... Use Polzinhunters billet chaincase cover... and an eye on all this stuff... don't just do "half the job". Especially with 3200 miles on the sled...
You should also be getting the primary serviced and balanced and the secondary bushings gone thru. (new springs too...if more than 1 season or 1000 miles on them)
Check your rear idler bearings as well
PREVENTIVE MAINTENANCE!!!
If you notice leaking fluids.. check where they are coming from..
You are supposed to check your chaincase oil level (sightglass) every ride.
Use a good quality synthetic chain oil like Polaris, amsoil, Redline.
at this point... pull the entire chaincase, install new upper and lower seals (Polaris has the best price). Install new uppper and lower bearings, install a new plastic cover and use the updat bracket plus insulation OR .... Use Polzinhunters billet chaincase cover... and an eye on all this stuff... don't just do "half the job". Especially with 3200 miles on the sled...
You should also be getting the primary serviced and balanced and the secondary bushings gone thru. (new springs too...if more than 1 season or 1000 miles on them)
Check your rear idler bearings as well
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I agree that you should change all jack and track shaft bearings while your at it! It will save you time and money in the long run. But I see that you have an 05 and in that case I am the only one currently making a billet cover for that model . They are 175.00 shipped in the states or one of these guys will probably hook you up with the polaris bracket if you budget does not allow for a billet cover. Good luck
mY bad... I mis read the year... Polzinhunters stuff rocks in qualtiy and design and he is the ONLY one that makes a billet cover for the 2005 chaincases... You cant go wrong with installing it... expecially with that HUGE heat sink of a stock muffler you are running.
Once a plastic cover becomes a leaker... IMO... time to replace the cover with a new one.
Once a plastic cover becomes a leaker... IMO... time to replace the cover with a new one.
^^DITTO...kreg is the MAN...period..
if you need a stock cover and update plate to get you buy, send me a PM..i dont need mine anymore after kregs amazing work!
cover
My chaincase cover is badly warped, I think I'm going to work a few OT shifts and buy PolzinHunters cover. I also purchased the tool to open the secondary clutch today and it still does not open, something must be broken inside the clutch, going to have to try and roll the belt off and take the secondary apart. I sure enjoy riding this 900 but the maintenance factor is huge. I'm used to riding my ol 96 580 Cat, owned it since 2001 and just gas and go, over 5000 troublefree miles. That being said, I'm committed to making this 900 work for me, I got it cheap, and I want to build it to last. As $$ allow I will add the better motor mounts, the chaincase cover, the intake boots, the FBF cable is ordered. It looks like I'll be riding the old sled now till some $$ roll in.
My chaincase cover is badly warped, I think I'm going to work a few OT shifts and buy PolzinHunters cover. I also purchased the tool to open the secondary clutch today and it still does not open, something must be broken inside the clutch, going to have to try and roll the belt off and take the secondary apart. I sure enjoy riding this 900 but the maintenance factor is huge. I'm used to riding my ol 96 580 Cat, owned it since 2001 and just gas and go, over 5000 troublefree miles. That being said, I'm committed to making this 900 work for me, I got it cheap, and I want to build it to last. As $$ allow I will add the better motor mounts, the chaincase cover, the intake boots, the FBF cable is ordered. It looks like I'll be riding the old sled now till some $$ roll in.
If they insist that the update was done, insist that they fix it.
DITTO!! i would take it to them and show them what the didnt do!
A
Aussie Niko
Well-known member
well the same thing happened to me today, no oil and a melted dip stick!!Tomorrow will see how bad the damage is!! I did have slipping going on for at least 20 miles on the trial. Would say the sprockets and chain are totalled.
A
Aussie Niko
Well-known member
well $275 later and i'm up and running again, chain cover, chain, tention wheel and top sprocket were totalled. There was no oil left in there and I don't know where it leaked out?? Is the sightglass on a aftermarket cover?
If its an 05 it doesn't have a sightglass it has the dipstick.
Yes. Kregs billet cover comes with a sightglass instead of the dipstick used on the oem plastic cover.
