Engine pulls over hard

[snowditch]

I'm doing my winter checklist: changing oil, checking DD, cleaning power valves etc. I thought I'd check Compression but I could not pull over the motor, thought oh s___ this thing is stuck from sitting over the summer. I pulled plugs and it pulled over ok. Reinstalled plugs and same problem. I grabbed the fogging oil sprayed down each plug hole and pulled over several times to lubricate engine good. I tried again but WOW still not able to pull over. Now I'm starting to think that when I cleaned power valves I got a little too much cleaner inside motor and on top of that I just added more with fogging oil. I put plugs back in left exhaust pipe off and started motor. Ya she popped off and ran, hit kill switch right away. After a few attempts to burn off fluid this thing still pulls over like my old 1000 in -10 deg weather. Can any one explain this?

 

[Cat800]

did it pull hard with the exhaust on it? If so maybe exhaust is pluged

 

[kiliki]

is your primary clutch off of it?

 

[snowditch]

Currently the sled is in pieces. Clutch off DD gears out rear skid out exhaust off hood off. I pulled it over with and with out the primary attached. No difference in how the rope pulls. This thing really acts like a high compression motor. I thought the primary clutch would help act as a flywheel but the problem isn't spinning the motor but getting it to freely turn over past the compression stroke. This happens with or with out the ign turn on.

 

[diggerdown]

Seen a rotax do that once, the guy got it started and knocked the crank out. His oil tank had drained into the engine over summer

 

[TINKER]

I had an issue similar to that and my power valve for some reason had slid down and had gotten into the piston. Pulled over hard but finally got it to fire and actually rode two rides but it had scarred the rings and piston and then finally quit running but it always pulled over hard.

 

[Vern]

Seen a rotax do that once, the guy got it started and knocked the crank out. His oil tank had drained into the engine over summer

My m7 did this two summers in a row before I finally bought a new oil pump. No engine damage though, just pulled the plugs out and pulled the piss out of it to push all the oil out. Made quite the mess squirting oil out the plug holes but would run fine all season long until long term storage again. Been fine since new pump.

 

[snowditch]

Ok I feel really stupid now! Start wrenching on sled again today so I put clutch back on but this time tighten the holding bolt. Before I put just enough pressure on clutch taper to hold in place long enough to test compression. I'm use to this because of my morse taper I have on my drill press. Again my intension wasn't to start it but check compression. Only thing I can figure now was that I did have too much fluid on piston creating a hydraulic effect raising compression much higher than a dry cylinder. As far as oil draining into engine with a full oil reservoir, that is somewhat true. My previous cat sleds never had so much oil sitting in inlet duct to throttle bodies. My dealer had told me Cat changed the check valves so oil will drain into motor with a full tank. C for yourself on 010 & 011 800's pull intake housing out and reach inside rubber duct at the begging of winter season. Only year this never happened was when I pulled oil out of tank at end of season to test this theory. Either way I found out the hard way that pulling over a motor with out the clutch attached is d__ near impossible. Amazing how much it adds a flywheel effect!

 

[Rixster]

Yeah, they are damn near impossible to start without the primary on. Plus, you should NEVER run it with the clutch off, the motor will rev with no resistance on it and could do some damage.

 

[snowditch]

I got it to fire off trying to burn off fuel charge but hit kill switch just as fast as it started. 1/2-2 sec runtime.

 

[arctic2009]

I got it to fire off trying to burn off fuel charge but hit kill switch just as fast as it started. 1/2-2 sec runtime.

Did you check to make sure a nice little mouse nest isnt inside of your exhaust can? Or did you plug the can with a rag over summer? Forgot about that one year, about 3 pulls and realized I left the rag in there.. haha

 

[snowditch]

Nope, engine ran briefly with out exhaust or power valves. Part of my checklist is to check for things like that. Should start new thread but does anyone reading this do anything special to summarize sleds other than gas treatment. Fogging, blocking exhaust, remove belt, replace DD oil, etc?