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Discussion Starter · #1 ·
I was coming off a lake after cruising at about 70 mph, put on the brake and then gave it (97 Polaris 700 sks, 5600 miles) a little gas. My sled made a bit of a vibrational noise. I stopped and took a look; it sounded like the noise was coming from the clutch or engine. I decided to head back home. About 1 mile later, going about 50mph, I went to give it a little gas and it made a VERY BAD NOISE, like something broke in the engine/clutch? The sled died and shut off on its own. Tried to start it again. I could pull it over, but it was quite hard and there was no chance of it starting. Does anyone have any suggestions of what broke or where to start looking? Thanks [V][:(][:(!]
 

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Could be a lot of things, but I'd be willing to bet you spun the crank, blew a bearing on the crank, or popped a piston. Maybe a combination of these. Either way, it doesn't sound good. You're going to have to tear her down to find what she spit out. Sorry.
 

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I know a friend that has a 97 RMK 700 and the excact same thing happened, it broke the crank..
 

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Here is 3 quick tests:

1. Pull the rope, if the primary clutch doesn't turn, you have a busted crank.

2. Pull the plugs and have some one gently hold a screwdriver down onto each piston, if one doesn't go up and down, broken connecting rod.

3. Look down inside the plug holes, and look for holes or damage to the pistons, also look at the pistons with the exhaust manifold off and look for melted rings and piston holes.

But it sounds like you are in for an engine teardown...you will find the problem sooner or later.
 

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i was racing once with some friends and my friend lifted my 440 and i gave it the gas to clear the track of snow, my next mistake was to jam the brakes when it was turning like 7500 rpm and then i heard a vibration, drove the sled home took it apart and found out i broke the pin on the connecting rod off. the only reason i could drive it home was becuase it was broke on an angle. That was a tough sled, it now has 16000miles...
 

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Discussion Starter · #9 ·
Originally posted by 500fasEnuf
[br]Here is 3 quick tests:

1. Pull the rope, if the primary clutch doesn't turn, you have a busted crank.

2. Pull the plugs and have some one gently hold a screwdriver down onto each piston, if one doesn't go up and down, broken connecting rod.

3. Look down inside the plug holes, and look for holes or damage to the pistons, also look at the pistons with the exhaust manifold off and look for melted rings and piston holes.

But it sounds like you are in for an engine teardown...you will find the problem sooner or later.
When I pull the cord, I can see both of the pistons going up and down and nothing looks very bad (by looking through the spark plug holes anyways). Also, the primary clutch does turn when I pull the cord, but there is some play in it if i grab it and shake it. I assume that there should be no play in it at all due to all of the power that is going through it. Does this point more to a problem with the crank bearing? Or something else? Thanks
 

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Crank bearings. If the clutch is moving.

You gotta tear it apart.
 

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Check the chain tensioner on the chaincase. The noise you heard - could it have been ratcheting, and the engine dying was just a coincidence? If not, you could have sheared off the shear pin on the stator.
 

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I was out with a guy driving a 93 XLT. It did exactly what you are describing it was a cooked crank bearing.

Rich
 

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[V]Crank. Bought one a few years ago used and first run downa lake the same thing. Mine was the crank. Good luck[8D]
 

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Well Scout, I think you have enough here to help you a by now. By the way...nice job guys, lotsa good posts here.

It certainly sounds like the crank bearing to me. The primary shaft may have a bit of play in it anyway, that is too hard to tell. But if it is tough to turn over, you have primary drivetrain problem.

Let us know what happens.

Time to get dirty.

(o;

DNO.
 

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Discussion Starter · #15 ·
One question. Should I attempt to fix or at least pinpoint this problem myself? I would like to try, but I have never taken an engine apart and I don't have a ton of tools (or shop manual). I am quite poor these days due to buying a new used truck and it sounds like this might be an expensive repair if I bring it to a mechanic to fix. Any comments, suggestions, pictures or warnings would be greatly appreciated. Thanks
 

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crank, been ther done that three times in 7500 miles. and believe me it's expensive. Costed 300 dollars each time i did it.
 
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