91 Exciter 570 Overheating - Snowmobile Forum: Your #1 Snowmobile Forum

tailtunz · 12-20-2005, 07:34 AM

I started up my 91 exciter 570 for the first time this year. It started up great and seems to run excellent. After a few rips around the yard I blew a water hose. One of the hose's coming from the water pump had been rubbing on the engine for a few years I guess and finally let go. So I cut a piece off and fixed that problem. But after a few more rips around the yard the temperature light came on again. What is causing this sled to overheat ? Is there a thermostat on the engine like on a car? Could it be stuck closed? Could there be a problem with the water pump? Worn belt or something? Sled was running great when i parked it last year? Any thoughts?

Cheers !!

tailtunz · 12-20-2005, 08:28 AM

Just to add a bit more to my previous post. When I parked it... I turned off the gas and ran the carbs dry. I added some fuel stabilizer to the 1/4 tank of gas left. Also I poured some oil down the cylinders. It is stored in a covered outdoor building with open end walls. Also threw the snowmobile cover on...and jacked up the back end. Before I started it I topped up the fuel with fresh gas and added some oil directly to the gas. Thats about it. It started right up after the lines and carbs filled with fuel. What hapened? Why does it overheat now?

IndianRvrShiver · 12-20-2005, 08:30 AM

Prolly an air pocket in the system. You will need to "burp" it!
Fill reservoir with coolant & run engine for a few minutes, then raise the front end up about 2' & run engine again. Make sure pressure cap is loose/off in each case.
Hope this helps!

SergeantDHall · 12-20-2005, 10:18 AM

There are several things you need to do! Yes, it does have a thermostat, which is located on the head, but, as stated previously, you need to get all the air out of the system. On the thermostat housing you have a screw to bleed air out of the system. Underneath your seat and at the rear of the machine you have another bleed screw. As stated before, raise the machine, add coolant and use the bleed screws to release the air pockets which can and will form when you have an accident like you encountered. After you have got the air out of the system, then start the machine and let it warm up, but continue to check your air bleeds for any air while it is running! Good Luck!

IndianRvrShiver · 12-20-2005, 10:32 AM

One more thing...........replenish system with 50/50 mix of glycol based anti-freeze solution! Do not used plain H2O!

tailtunz · 12-20-2005, 11:30 AM

Thanks I will definetly be bleeding the cooling system. I will let you know if Im successful. I definelty will not be leaving the yard until I know for sure it is staying cool. I definetly shut the machine down right away as soon as the temp light had come on. I did not want to fry this at the beggining of the snow season thats for sure.

Happy holidays
Happy sledding

Cheers
Jason

tailtunz · 12-21-2005, 12:24 AM

Ah yes ...much better now. The cooling system definetly needed to be burped. I drove the sled up an embankment...took the rad cap off...started up the sled...kept adding fluid until it was full. Then I took the bleed bolt out from the top of the engine where the thermostat is....until fluid started coming out...ahhhh much better now.... I now see alot more activity when the rad cap is off. I drove around the yard for awhile and it seems to be keeping cool once again. I may bleed it one more time just to be sure there is no air pockets left.

Thanks for your help.

Cheers !!

IndianRvrShiver · 12-21-2005, 09:07 AM

Another happy ending!!

SnowRida · 12-21-2005, 09:36 AM

Sounds greaaaat. Keep that Yammy runnin good!