Not sure what is wrong, but here is the end result. After about 5 mins of slow riding, my 2001 SKS 700 just turned itself off. Stalled out and died. Hmmm. Started it up again and continued for a few more mins. Stalled again. Started one more time and then it stopped for good. I could not pull the start cord. Motor seized up. Let it sit all night in the cold and today I turned the clutch and the motor moved. Got the sled home now and trying to figure out what went wrong.

I have recently changed the oil filter, and chaincase oil and new plugs. I suspect that I have an air bubble in the oil lines and I have cooked the motor. All the coolant and oil lines were removed in the service.

Seems now from reading more internet pages, I should have mixed some oil in the gas (50:1). Things you learn. ARGH

So, is my ride dead now? Should I open the motor and see what it looks like? Just take it to a dealer and let him do that? Mix some oil in the gas and try to get the air bubbles out of the lines and pretend nothing has happened?

What will the plugs tell me if I look at them now? There were brand new.

Thanks for any help. Very annoyed right now as we have about 2 feet of fresh snow on the ground...

thanks

scott

that's sounds likely... whenever doing any oil pump/line/filter change... the pump should be bled.. there's a bleed screw on the pump that needs to be opened to bleed all the air from the lines.. otherwise the engine will starve for oil... I would doubt that the plugs would have some traces of aluminum on them... if so... a closer inspection is in order... you could remove the carbs and look at the piston through the ports to look for scoring... same with the exhaust... if so... rebuild time... myself.. I would more than likely open it up.. once you do have it rebuilt... run oil in the gas... and you can remove the oil feed lines while idling and turn the oil pump lever to make sure the oil is flowing and then reconnect the lines to the engine.. and you should be in business...

Along with what ddaxe said, I would put each piston at bottom dead center and get a bend-a-light in the cylinder and look for scoring on the cylinder walls. Also, a compression check will let you know if the pistons have been damaged. It's very likely that you will need two new pistons, and may also require some cylinder repair, depending on if the cylinder walls were scored.

Update.

thanks for the replies. I have now found the bleed screw and have oil now flowing to the motor again. I have burned a gallon of oil/gas and now have the oil flowing again. It seems to sound ok. I did look at the plugs and did not see anything too bad on them. As there were new, they just had some black soot on them which I think should be expected. I did not see any metal on them. I am going to try and run it this weekend around the house and see how it runs. Might remove the cover and take a peek in the cylinders to see what they look like. Assume it should be easy enough to see any damage on the walls.

will try and do a compression test as that should tell me a lot I think. annoyed I did not know/read the manual good enough to bleed that oil line. first time I have worked on a snowmobile. now I know. hope it did not cost me too much $$$

good to hear... hopefully there's not too much damage in there... time will tell...

Update:

my neighbor has a drag racing car, so nice to have access to all the tools you ever need. Loaned his compression gauge and measured 90 psi in left cylinder and about 93 in the right side. Did this numerous times and got the same readings. Those numbers seem good to me, so I think I am ok. Not sure of exaclty what numbers to have, but from what I can find, it is about 120 for a brand new motor and 90 for a used motor. Anyone have any better numbers to use? 2001 sks 700. Fingers crossed rest of the season...

A new sled should be around 120-135,,normal is around 105-125 around a 100 you should
replace the rings and under 90 you probably have sum cydinder scoring or a stuck ring.

90 would be good for a small cc engine like a 340 or 250.
With 90 psi you may notice your sled is hard to start sometimes.
If you did this on a cold engine,your compression is probably closer to 100.

also to see if it is the rings,spray some oil in to the cylinders if you get better results you may have worn; stuck or a cracked ring