97' Yamaha VMax XTC Overheating - Snowmobile Forum: Your #1 Snowmobile Forum

dwright071971 · 01-14-2013, 09:07 AM

I am new to Snowmobiling but am pretty mechanically inclined. I have a 97' Yamaha VMax XTC and need to know what steps to go through to diagnose what is causing the overheating.

Last weekend, in northern Michigan, I went for a ride and after abour 10 minutes the temp light started flashing red. I had checked the coolant level in both the reservoir and in the hose (opened the cap) prior to going out. I opened it up and found that the reservoir was still full and squeezed the hose leading to the thermostat a few times and found that it started flowing as the hose started getting pretty hot. I pulled the cap off and watched the fluid in the hose and it seemed to be pumping through as well.

I'm guessing that maybe I have a bad thermostat but I don't know how the system fully works. Does it have a radiator? Does the cooling of the system also rely on snow being thrown up onto the radiator? What things should I check for. How would I know if the pump was going bad? I ended up driving it for a while trying to baby it and after quite some time the top to the reservoir blew off so I turned it off and didn't run it anymore.

mmsrx · 01-14-2013, 05:49 PM

I can't remember but I think the heat exchangers are under your feet. 1 exchanger is in front of your track. If you have no snow you will over heat. When ever my sleds got hot I put snow on the running boards to cool it off (let it idle til the light is off). You said the antifreeze is flowing but mabey the thermostat is starting to stick.

yamadad4 · 01-14-2013, 06:43 PM

the equivalent of a radiator is what i refer to as heat exchangers. you should have four total. one under each footboard, one at the rear of the tunnel(most times) and one at the front of the track in the tunnel.

low or no snow conditions limiting to what snow sprays up on the exchangers can create a hot condition. your water pump is belt driven and could be stretched, worn, even broken. down at the recoil housing theres an observation hole you can check to see if the belt is spinning. take it from there.

i believe they dropped the t-stat after 96, dont recall the 97's having one. easy to check if you have one and easy to test one if its there.

dwright071971 · 01-15-2013, 10:37 AM

I had already looked at the belt and found that it was, in fact there and moving. I don't know if it's stretched or worn so I'll pull that apart and check it.

As for the low or no snow statements. There was probably a good 4" at least of packed snow on the groomed trail so I would think that would be the type of conditions it was meant to be driven in.

I plan on pulling the hoses and trying to flush out the system. If there is anything that I might damage by doing this please let me know.

Any other thoughts would be greatly appreciated and thanks for your help so far.

kenora · 01-15-2013, 04:55 PM

i have the same sled. I find that the floorboard heat exchangers get warm then hot to the touch after idling for 10 minutes or so. If they are both getting hot and the crossover pipe at the rear under the snow flap is hot then there is coolant flowing through the system.
I have never had my overheat light come on but fwiw evn after a hard ride on a packed trail (poor cooling on a trail) I can still put the palm of my hand on top of the head for a count of 10 so if yours is hotter than that there must be a blockage somewhere. I worry more about the lack of cooling to the sliders on low snow than overheating the motor.

yamadad4 · 01-15-2013, 09:22 PM

save some labor and just try and bleed the system.

as for the belt, there should be about 8mm deflection using 26lbs of force. use the inspection hole as your guide and get a feel for the 26 lbs using the bathroom scale. a 1/4 - 3/8" dowel works great.

is the temp light constant on or blinking?

dwright071971 · 01-17-2013, 08:01 AM

Yamadad4 - The temp light is blinking.

yamadad4 · 01-17-2013, 07:45 PM

does there seem to be a sequence to the blinking? those sleds have a self diagnosis function that will flash a sequence code to indicate an issue.

seems like an overheat was a constant series of short flashes. a code flash usually starts with a longer flash followed by a sequence of short flashes.

the long flash is just under 1 second, the short flashes are quick and maybe 1/4 second.

Yamaha440 · 01-17-2013, 09:21 PM

Just to comfim the above, flashes indicate a problem with many sensors that are in the system with a diagnostics feature.

If it were overheating it would stay steady on.

Sorry I can't go into specifics, I don't have my service manual near me at the current moment.

If I remeber correctly, the manaul also said that the diagnostics function was only avalable on deluxe models.
On the deluxe model, the left lamp, below "highbeam", has "diagnostics" written on it, with only the "low oil" lamp on the right.
A normal sled will have "temp" lamp below the "highbeam" lamp on the left, and a "T.O.R.S." lamp below "low oil" lamp on the right.

dwright071971 · 01-18-2013, 12:18 PM

Not sure what the deluxe model is but I am getting a service manual within the next couple of days to see what it says about the blinking. I do know that mine has the high beam indicator on the left with the temp light below it on the left.