Ok, I just got my 94 XLT Special 580cc about a month and a half ago, had about 3200 miles on it when I got it and has been running wonderful. Today, after about 80 miles with no problems, it out of the blue starts going clackety clack and sounds like the chain is not engaging the teeth. I was able to drive it to a safe spot for pickup about a mile and a half away, and once in a while it would actually sound and drive like it was engaged. Did my tensioner break, or go out of adjustment? I am a newbie and pretty handy with cars but admittedly know very little about snowmobiles, but willing to learn. Any help or advice appreciated.

Thanks

Take the cover off and have a look, I bet your chain actually just came loose, the tensioner is there see if it moved. Its only 4 10mm bolts to get the cover off...

Take the cover off and have a look, I bet your chain actually just came loose, the tensioner is there see if it moved. Its only 4 10mm bolts to get the cover off...[/b]
Um, I know this is a really stupid question but could you give me a bit of an idea where the cover is? I really am not this mechanically ignorant, but I do feel a bit lost under the hood of this thing.

Thanks for the post, makes me feel a ton better already.

On the right hand side if you open the hood, by the exhaust muffler.

The pull cord should run right over the brake assembly, this is the chain case under that.

Do you have an owners manuel?

It shows how to check the tension of the chain, far easier than anyone here trying to explain it to you. Hope that helps.

Thanks for the help gentlemen, I will check it out tomorrow. I don't have a manual, but will google one up. I will let you know how it turns out.

I also have more questions about the ski allignment and front suspension, but will wait til I am past this chain ordeal, ughhh!

What you find inside may or may not be obvious and helpful.

A question: does the machine move along readily or not? If not, then there is an obvois problem to be seen. If it does move and you're dealing with a noise problem, then it may not be easy to see.

Noise in the chain case, especially "clunking" can be from broken teeth (which can be "run through the gears") or it could also be a broken chain link. Neither of those problems is always easy to see, but both can wreak havoc if not corrected.

At the very least, remove the muffler, pull that cover, and look inside. Clean everything out real well and check for wear. (Take the chain off and inspect it closely. I broken link may flop loosely; then again, it can also slip back in line, unnoticed.) While you are in there, look closely at the bearings. There are two; one low and one high. The upper one is the jackshaft, the lower the drive shaft. The balls and their retainer may be covered by a seal but it should be obvious that they are aligned or not.

It would also be wise to look at the bearings on the opposite ends of both shafts. The lower one has a cable running from it to the speedometer. Loosen the three nuts and look inside. Make sure the bearing is solid and smooth (if you can turn it). Also, make sure there is not water or rust inside the cover and that it is full of grease. Check the upper shaft, the jackshaft, as well. The secondary clucth is on it. You probably removed it to access the lower shaft easily. There should be no play in the jackshaft end. If there is, that is likely the problem.

Clankety-clanking in often bearing related.

Clankety-clanking in often bearing related.[/b]

Yes, I had this same problem. I was riding one day then all the sudden I got what felt like the track was ratcheting or the chain was mucked up.

It turned out to be the bearing on the lower gear. It was covered in rust and siezed up, causing the clankety clanking.

Dont be afraid to tear into the sled. I'm also a newb rider (2nd season) and had never worked on a sled until this season.

So far I've had to swap engines, replaced a track, replace bearings, and other chit. It's all simple. At least with the older sleds. Im sure the newer sleds are a little more challenging.

What you find inside may or may not be obvious and helpful.

A question: does the machine move along readily or not? If not, then there is an obvois problem to be seen. If it does move and you're dealing with a noise problem, then it may not be easy to see.

Noise in the chain case, especially "clunking" can be from broken teeth (which can be "run through the gears") or it could also be a broken chain link. Neither of those problems is always easy to see, but both can wreak havoc if not corrected.

At the very least, remove the muffler, pull that cover, and look inside. Clean everything out real well and check for wear. (Take the chain off and inspect it closely. I broken link may flop loosely; then again, it can also slip back in line, unnoticed.) While you are in there, look closely at the bearings. There are two; one low and one high. The upper one is the jackshaft, the lower the drive shaft. The balls and their retainer may be covered by a seal but it should be obvious that they are aligned or not.

It would also be wise to look at the bearings on the opposite ends of both shafts. The lower one has a cable running from it to the speedometer. Loosen the three nuts and look inside. Make sure the bearing is solid and smooth (if you can turn it). Also, make sure there is not water or rust inside the cover and that it is full of grease. Check the upper shaft, the jackshaft, as well. The secondary clucth is on it. You probably removed it to access the lower shaft easily. There should be no play in the jackshaft end. If there is, that is likely the problem.

Clankety-clanking in often bearing related.[/b]

Thanks so much for the detailed information. Fortunately, (can't believe I am saying that) my problem does interfere with the snowmobiles movement and was pretty obvious when I removed the cover. The chain is very loose, with a screwdriver I can easily move it away from the gears. Luckily the gears still look like they are in perfect condition and the chain as well. Looks like a lot of tension bolt, about 2.5 inches sticking out of the cover, so unlikely that it has ever been tensioned before.

Over the summer I will definitely do some more work using the information you provided to more thouroghly check out the bearings etc... so sincerely appreciate your time.

Around here I will be lucky to have 3 more weeks of season so want a quick turnaround so I can get back at it. So for now, a quick cinching of the tensioner and away I will be going.

Other question for you though, the chain case was basically free of oil, judging by the dipstick it should have oil in it. What kind is best for a 94 polaris? Also, how tight should I make the tensioner onto the chain?

Thanks again for any help.

Must be nice snowmobiling on the strait, I can't even imagine!!!WOW!!! How cool is that????

Take the cover off and have a look, I bet your chain actually just came loose, the tensioner is there see if it moved. Its only 4 10mm bolts to get the cover off...[/b]
Thanks, you were right on. How tight should I get the chain, looks like it has never been tightened, also little or no oil inside the cover, What is recommended?

Thanks again, you are the MAN!!! The Snowmobile MAN of course.

as tight as you can with your fingers and then back off a quarter to half a turn.

as tight as you can with your fingers and then back off a quarter to half a turn.[/b]
Thanks much!!!