Anyone here work on snowmobiles?

[POINTER94]

I have an overheating problem with a 99' Mach Z, skidoo. I just rebuilt the top end and it runs great! But every once and a while it overheats and then shut down. Is there an overheating sensor that shuts it down? What could cause this?

 

[roscoe]

Re: Anyone here work on snowmobiles?

The heat of summer. Sorry, couldn't resist.

 

[Bindernut]

Re: Anyone here work on snowmobiles?

I think a 99 Rotax would have a thermal shutdown switch, but I'm not positive. I work mainly on vintage sled engines and don't have any service manuals newer than 84 to check.

Biggest thing is to determine why it's overheating. Does it get doggy before it shuts down or is it an immediate kill? Why did it need top-end work and what was done? Is your mixture too lean?

 

[POINTER94]

Re: Anyone here work on snowmobiles?

Bought it used and the guy ran it on 3 year old gas, scorning the piston nearest the pto. The guy gave me the money to rebuild the engine. (Parts) Wesco pistons, replaced the needle bearings, gaskets, honed the cylinders, etc. He used this as a backup sled. All cylinders at 138psi. It is creepy fast as I was takin on modified 800 2 cylinders and winning. Its got long legs.

It runs fine except the gauge starts to run hot then shuts down. I have burped it several times since the rebuild. It only happens once in a while.

 

[muskyone]

Re: Anyone here work on snowmobiles?

hey i have the manual for that sled i'll bring it in july if ya want but it sounds like you have air in there or a bad pump or tstat or or

 

[Rancherlee]

Re: Anyone here work on snowmobiles?

check the crankcase seal on the PTO side, it maybe leaking causing a lean condition on that cylinder. Also verify that the jets in the carb are the correct ones with a skidoo dealer. Tripple check that there are not any air bubbles either in the cooling system by lifting the back up in the air then the front up in the air while its idling to purge it out.

 

[muskyone]

Re: Anyone here work on snowmobiles?

if that engine is the same as mine it has differant size jets left and right like i said i can bring you the manual in july

 

[Lucrestyle]

Re: Anyone here work on snowmobiles?

www.dootalk.com your best bet!