2000 800 rmk engine questions

[moeszyslak]

sorry for the lenghty write up for the description of what happened.

i have a 2000 800 rmk. ihad some problems today, i was riding along and all of a sudden the engine was bogging and i didnt have any power. opened the hood and found a loose spark plug, tightened and started, ran like normal for about 100 yards. then it did the same think again, pulled plugs, one was fouled so i replaced it, started and ran like normal again but it only made it another 100 feet and a died. i grab the pull rope and it wont pull out, so i try to turn engine over with the clutch and it felt fine and turned . it didnt feel like it was locked up or anything. so by this time i am somewhat pissed so i try to start it again and on the second pull the rope broke.

when i returned home i pulled the head to see if there was any damage but everything looks good, no ridges or anything. i fixed the pull rope but i dont know what else would cause my problem that i can check without tearing the motor apart anymore. what do you think could be some causes of this. i am thinking worst case, something with the crank is the problem but i am wondering if there is any other possible thing that it could be. i was wondering if the magneto could have possible quit working and loss of spark. i ont know just thinking. i am thinking about putting everything back together and seeing what happens.
thanks for any info and please ask me any questions that might help

 

[TROLLCAT]

does the motor roll over by hand freely no tight spots both directions , inside head and top of the pistons are they the same color ,if they aren't the same color something is coming apart [ danger will robitson danger ]

 

[moeszyslak]

does the motor roll over by hand freely no tight spots both directions , inside head and top of the pistons are they the same color ,if they aren't the same color something is coming apart [ danger will robitson danger ]

it does turn both directions, how much resistance should there be rotating by hand with the plugs out. the heads and pistons were close the the same color, one was more black that had the fouled plug

 

[TROLLCAT]

no tiny silver or gray particals rolling over by hand no plugs in the resistance should stay the same 360 degrees magnets in flywheel will mess with you a liitle bit , how many miles on it ,

 

[CR500R]

sorry for the lenghty write up for the description of what happened.

i have a 2000 800 rmk. ihad some problems today, i was riding along and all of a sudden the engine was bogging and i didnt have any power. opened the hood and found a loose spark plug, tightened and started, ran like normal for about 100 yards. then it did the same think again, pulled plugs, one was fouled so i replaced it, started and ran like normal again but it only made it another 100 feet and a died. i grab the pull rope and it wont pull out, so i try to turn engine over with the clutch and it felt fine and turned . it didnt feel like it was locked up or anything. so by this time i am somewhat pissed so i try to start it again and on the second pull the rope broke.

when i returned home i pulled the head to see if there was any damage but everything looks good, no ridges or anything. i fixed the pull rope but i dont know what else would cause my problem that i can check without tearing the motor apart anymore. what do you think could be some causes of this. i am thinking worst case, something with the crank is the problem but i am wondering if there is any other possible thing that it could be. i was wondering if the magneto could have possible quit working and loss of spark. i ont know just thinking. i am thinking about putting everything back together and seeing what happens.
thanks for any info and please ask me any questions that might help

I had the same sled, what you describes sounds similar to one of the 4 engine blow ups I had, the crank broke on the mag side on mine, I lost power but it would still run at idle, shut it off, checked the typical things, fired it up appearred to run good, give it some throttle no power, then died. Attach tow rope tow it 29 kms to the truck. Pull the the cover off the mag side and check it.

 

[heavy d]

you could also look in thru the exhaust(after removing pipes), and see if you dropped a piston skirt. ????????????

 

[bdietz]

could be a bad crank brg
I had that happen on a XLT
pto side brg was bad put in a new one and was good

 

[moeszyslak]

no tiny silver or gray particals rolling over by hand no plugs in the resistance should stay the same 360 degrees magnets in flywheel will mess with you a liitle bit , how many miles on it ,

the guy i bought it from (a month ago, that is the really shitty part) said that he rebuilt it about 700 miles ago, and by looking at the cylinder walls you can still see the pattern from being honed like it is almost new still. this ws only my 4th trip out so i have only put about 200 to 250 miles since i have had it.

 

[moeszyslak]

I had the same sled, what you describes sounds similar to one of the 4 engine blow ups I had, the crank broke on the mag side on mine, I lost power but it would still run at idle, shut it off, checked the typical things, fired it up appearred to run good, give it some throttle no power, then died. Attach tow rope tow it 29 kms to the truck. Pull the the cover off the mag side and check it.

i already have the pull rope assembly off to fix the rope, what do i want to look for, is there anythng else you can think of to check.

 

[trench]

I believe these motors have a resistor tied in to the cooling system that will pull the engine RPM's down to protect it when it starts overheating. If it goes bad the engine will stumble and not get full rev's, easy cheap fix if that is it. Oops I re-read your post the resistor should not cause it to shut down.

Trench

 

[TROLLCAT]

look between clutch and crankcase inspect seal , leaking , damage from heat if that looks good put it back together and try it,two new plugs good luck

 

[CR500R]

i already have the pull rope assembly off to fix the rope, what do i want to look for, is there anythng else you can think of to check.

If I read this right you were able to rotate the clutch but the pull cord wouldn't pull out, and you ended up breaking the pull cord. Leads me to believe the flywheel may be jammed unless something else failed in the rewind assy. You said you fixed the pull rope but did you check the flywheel/ water pump drive pulley assy, for any sort of play or movement up/down, in/out. Can you rotate it, if so hold the clutch still, and try to rotate the flywheel in both directions, there should be no play whatsoever. When mine broke it snapped right behind the seal flush with the bearing and took out the stator. I also had one break at the center between the cylinders, so make sure when you rotate the crankshaft the pistons are moving properly, one should be at tdc, the other bdc. These engines had horrible crank issues. Here's a link to an online parts catalogue for reference Polaris Parts, Polaris Snowmobile Parts, Polaris ATV Parts, Polaris Ranger Parts, Polaris Accessories at wholesale prices Hope this helps.

 

[moeszyslak]

If I read this right you were able to rotate the clutch but the pull cord wouldn't pull out, and you ended up breaking the pull cord. Leads me to believe the flywheel may be jammed unless something else failed in the rewind assy. You said you fixed the pull rope but did you check the flywheel/ water pump drive pulley assy, for any sort of play or movement up/down, in/out. Can you rotate it, if so hold the clutch still, and try to rotate the flywheel in both directions, there should be no play whatsoever. When mine broke it snapped right behind the seal flush with the bearing and took out the stator. I also had one break at the center between the cylinders, so make sure when you rotate the crankshaft the pistons are moving properly, one should be at tdc, the other bdc. These engines had horrible crank issues. Here's a link to an online parts catalogue for reference Polaris Parts, Polaris Snowmobile Parts, Polaris ATV Parts, Polaris Ranger Parts, Polaris Accessories at wholesale prices Hope this helps.

the pull rope broke because of so much drag inside the motor. i believe it is a bad crank bearing. cylinders look good, there is alot of drag while trying to rotate by hand. i dont have a puller to pull the flywheel so i am taking it to a shop this week to have it checked out. i am going to go with the slp tough guy bearing kit as long as the crank is still good to use.

 

[CR500R]

Curious as to what you found wrong with it????

 

[s/b tech]

Let us know how it all works out and good luck!!!!!