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Discussion Starter #1
Just got my predator back together. Took it out for short none crazy drives no problem. Suddenly after getting on it it would suddenly nose dive and make a horrible sound. Pulled the starter off and took apart and it was in pieces. Bought a new one and put it in. Same thing happened. Wondering if this could be the one way sprag clutch suddenly back lashing and ingaging suddenly and making the starter do 6000 RPm? Help. This is getting expensive. 03 500 predator
 

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Welcome to the board.
 

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I do not have a predator, but I would first ask......Does the starter drive disengage when you let off the switch? If the starter drive is sticking or the switch is sticking keeping it engaged in the flywheel that could cause it.
 

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Discussion Starter #5
The starter does disengage when you put start it. I know that it is always connected to the gears though, hence the one way sprag clutch. What would make the flywheel spin after the motor is started. The only thing I can come up with is the one way sprag clutch allowing it to engage intermittently?
 

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did you change the bendix when you replaced starter...the spring in the bendix may be weak cause the gear to creep back onto the flywheel....
 

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To clarify the terminology, so we are talking about the same parts: the flywheel is connected to the crankshaft and spins all the time the engine is running. The bendix or starter drive is connected to the end of the starter motor and should only turn when the starter is engaged. The process of the starter motor turning causes the bendix to move out on the end of the shaft and engage the teeth on the flywheel. Once the engine is started, or when the key/starter switch is released, the bendix should disengage from the flywheel. There is a one way clutch in the bendix, but it will stay engaged in the flywheel teeth until the starter switch cuts power to the starter.

If the bendix does not release from the flywheel when the engine starts and the switch is released, the bendix could cause the starter motor to turn with the engine speed and could be causing you to blow up the starter motor. They are not designed to turn that fast or for that long.

Also, if the switch is sticking (my 600 is doing that right now, new switch is waiting for installation) then the bendix will stay engaged in in the flywheel teeth and trash the starter.
 

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To clarify the terminology, so we are talking about the same parts: the flywheel is connected to the crankshaft and spins all the time the engine is running. The bendix or starter drive is connected to the end of the starter motor and should only turn when the starter is engaged. The process of the starter motor turning causes the bendix to move out on the end of the shaft and engage the teeth on the flywheel. Once the engine is started, or when the key/starter switch is released, the bendix should disengage from the flywheel. There is a one way clutch in the bendix, but it will stay engaged in the flywheel teeth until the starter switch cuts power to the starter.

If the bendix does not release from the flywheel when the engine starts and the switch is released, the bendix could cause the starter motor to turn with the engine speed and could be causing you to blow up the starter motor. They are not designed to turn that fast or for that long.

Also, if the switch is sticking (my 600 is doing that right now, new switch is waiting for installation) then the bendix will stay engaged in in the flywheel teeth and trash the starter.
So the starter is always connected to the flywheel on the predators. that is the reason for the 1 way sprag clutch. I have the manual. It shows the the starter gears and all connect to the flywheel. So the way I understand it is the starter is engaged and turns the flywheel. but then when started the flywheel should not spin anymore after that. I added some attachements so you can see.
 

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Ok I see what you mean now..there is no bendix either ...first time I seen a starting system like that....

you sure the flywheel does not spin after its started...I think one of them other gears is suppose to go one way...once its started it just fre spins..and that may be stuck ir seized so it does not free wheel and makes the starter spin once engine fires off...its the logical way any ways...
 

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First time I have seen that kind of system too, but I have to agree with al53. the flywheel is bolted to the crankshaft and is used to power the magneto, charging system and connect the crankshaft to the transmission. On the belt drive machines it balances the vibration from the clutch on the other end. It has to turn with the crankshaft. I would have to guess there is another gear in there that should spin free when the engine is running but isn't for whatever reason.
 

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First time I have seen that kind of system too, but I have to agree with al53. the flywheel is bolted to the crankshaft and is used to power the magneto, charging system and connect the crankshaft to the transmission. On the belt drive machines it balances the vibration from the clutch on the other end. It has to turn with the crankshaft. I would have to guess there is another gear in there that should spin free when the engine is running but isn't for whatever reason.
Sorry guys, but there isn't any disconnect between the start and the Flywheel at least that I can see. The starter is directly connected to the first gear which is then also connected to the next gear down in the middle, which is then connected to the flywheel. The only thing I can understand is that the flywheel has the one way sprag clutch on it which then doesn't allow the flywheel to spin anymore, but the outer part does which powers the charging system. Thoughts? I am thinking off pulling off the whole flywheel assembly and replacing the one way sprag clutch????another 100 bucks or so.
 

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ok looked up the fly wheel assembly and see what you mean now....with out looking it up I would of never guessed it worked like that....

here is what i was looking at... 500 one way clutch | eBay...

now I completely see what you mean and also learned something....so yes that sprag clutch inside the flywheel may have siezed ..thats the strangest system I ever seen....but i agree with you..may be time to pull flywheel and check out stuff inside....when you do please put up pics ..i would like to see the assembly...just curious....good luck..glad i am clear on what your saying..I was in left field and lost there/...lol
 

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Ok, I get it now...I see what you mean now with the 1 way clutch. I looked up the parts breakdown. The outer part is not the flywheel, but just a starter gear. That is connected through the one way clutch to the flywheel. The engine starts and the starter gear is supposed to free wheel, while the flywheel keeps spinning with the crankshaft. Strange system to be sure. You should be able to test the one way clutch by just turning the gear. It should lock up the way the starter turns it, but move freely the other. If it binds up at all, it could be turning the starter.

Thanks for posting this, I enjoy learning new things! That is still the strangest starting system I have ever seen. Probably what was necessary for the engineers to be able to fit the starting system in the smaller crankcase.
 

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Discussion Starter #14
First time I have seen that kind of system too, but I have to agree with al53. the flywheel is bolted to the crankshaft and is used to power the magneto, charging system and connect the crankshaft to the transmission. On the belt drive machines it balances the vibration from the clutch on the other end. It has to turn with the crankshaft. I would have to guess there is another gear in there that should spin free when the engine is running but isn't for whatever reason.
Well I think I have it figured out. I think when I had a clutch bolt snap and grind problem there was some metal in the engine. So the flywheel is right up against the main nut on the main drive shaft. I think some metal got in between and got too hot and seized the two together which makes the flywheel spin the wrong way which then makes the start spin at what ever rpm the motor is at. Well I took it all apart and put it back together. I couldn't find any more metal but am completely draining the case just in case and replacing oil filters.
I have to agree that this is some weird engineering on Polaris's part. Hopefully I will drive it now and wait for the next issue to arise. Thx all for reading!!!
 
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