I was out riding a bit tonight and my sled shut down again. This time, right before it quit I felt a loss of power, then ya it quit. The motor was tight again, and I know it wasn't the primary because it was all the way open and the belt was loose. I wiggled the primary and the engine came loose, started it up and I was able to get back home running on 2 cylinders. I got home and the first thing I did was pull the plugs. The PTO and Middle plugs were a nice golden brown, but the mag side was a light gray and had some textured buildup on it. Then I notice that the carb vent hose that goes into the airbox was unhooked, must've missed that when I put the carbs back in. hmmm....
I'm used to 4 strokes, so forgive my ignorance, but what exactly happened there? Did the mag side piston seize or what? Does it have anything to do with that vent hose being unhooked, wouldn't that affect all 3 cylinders?
I'm used to 4 strokes, so forgive my ignorance, but what exactly happened there? Did the mag side piston seize or what? Does it have anything to do with that vent hose being unhooked, wouldn't that affect all 3 cylinders?
Also here's the plugs, I didn't have a very good camera though so it's not a good pic
davessrx
New member
sounds like that cylinder got leaned out and burnt up. Check your compression, I bet it is low and it's time for a rebuild. Could have been caused by a lot of things....common lean conditions are carbs dirty/plugged and crank seals that leak.
daman
New member
Oh no.....that don't sound good, pull the head off and take a look. 
I need to get a service manual, I thought someone on here had a copy on their computer that they could email to people?
I could probably still take it off tonight, it there anything special I should know other than un-bolt it? How do you go about draining the coolant from the head before you take it off?
I could probably still take it off tonight, it there anything special I should know other than un-bolt it? How do you go about draining the coolant from the head before you take it off?
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that grey on the plug is your piston, melting from detonation and lean air/fuel mixture. You have problems somewhere, dirty carbs, airleak, wrong jetting.
you drain the coolant by the waterpump drain bolt located on the front of the engine, its a 10mm headed bolt with a copper sealing washer, its marked "DRAIN" right next to it, its right between the pto(clutch) and center cylinder on the waterpump cover.
you drain the coolant by the waterpump drain bolt located on the front of the engine, its a 10mm headed bolt with a copper sealing washer, its marked "DRAIN" right next to it, its right between the pto(clutch) and center cylinder on the waterpump cover.
shortstop20
New member
- Joined
- Mar 6, 2005
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redsnake3
New member
any white powder on the piston top? check the head gasket to make sure that when it gets hot there isnt coolant pumping into the cylinder and causing a cold seizure.
Well I took it apart, here's what I found:
Skidooslayer687
Member
ouch not good at all
Besides replacing the piston(duh...lol) what else generally needs to be done, and what things should I look for? I know the cylinder pic is a bad one, but it looks like aluminum sticking to it, is that still usable? Does stuff get into the cases, will I have to get into those? The powervalve seems to be stuck in the cylinder, I can move it about half way then it stops...I dont want to to too rough with it, I don't want to damage it. Also, I can't seem to get the piston pin out. I got the circlip off the mag side and tried to get it out that way but it seemed solid in there, again I don't want to be too rough with it. Any advice on this would be great...thanks
That really to bad man, hope you can get your parts before Xmas & get out riding…this is the winter we are all waiting for…