The Situation: temp light comes on whenever riding at +45-50mph for anything more than 1mile. Even in 4in of fluffy new snow at -5F and while blipping the throttle to try and throw some snow on the cooler. The fan is constantly on once the sled warms up. I had a few temp light occurrences last year due to Skinz float flate filling with snow in the powder so i trimmed it and this year i installed a Roest vent. Now temp light comes on all the time.
Been reading the overheating info to find my issue the only remedy i can find is replace the coolant with maybe some water wetter. Any other suggestions?
Going to dealer anyways to have the starter selonoid replaced (starting is now a total crap shoot) and all they suggested was to add the MTX cooler, but there must be another way.

Been reading the overheating info to find my issue the only remedy i can find is replace the coolant with maybe some water wetter. Any other suggestions?
Going to dealer anyways to have the starter selonoid replaced (starting is now a total crap shoot) and all they suggested was to add the MTX cooler, but there must be another way.


- Joined
- Nov 1, 2009
- Messages
- 3,564
- Reaction score
- 88
- Points
- 1,483
- Location
- Winnipeg, Manitoba
- Country
- Canada
- Snowmobile
- 2009 Phazer RTX
Do you know the water/anti freeze ratio? If you have too much antifreeze and not enough water it will not be very efficient to disperse the heat, is what i have been told.
Does the water pump circulate? Thermostat working correctly?
Does the water pump circulate? Thermostat working correctly?
snomaniac
Expert
Have the dealer, or yourself change your anti freeze be sure it's 50 50 then add couple ounces water wetter.
nytroman20
Expert
Mine did this until I bled the system.... Put the sled on a lol incline and let her run with the rad cap off.... Been fine since
sleddingfarmer
TY 4 Stroke God
Add a bunch of vents, check your coolant ratio, add water wetter.
If all that doesn't work, add the MTX cooler and your problem will be solved. I had a bunch of over heating too, but never saw the light after I put the mtx cooler on. Not worrying about overheating is a good feeling.
If all that doesn't work, add the MTX cooler and your problem will be solved. I had a bunch of over heating too, but never saw the light after I put the mtx cooler on. Not worrying about overheating is a good feeling.
Grimm
TY 4 Stroke God
- Joined
- Apr 15, 2005
- Messages
- 4,989
- Reaction score
- 234
- Points
- 1,573
- Location
- Ottawa, Ontario
- Country
- Canada
- Snowmobile
- 2018 MXZ 850
I've read instances where snow/ice build up at the tunnel exchanger, essentially cutting off the ability to throw more snow onto it for cooling. That may explain why that even riding in 4 inches of snow, you are still overheating. Have you taken at look at the front exchanger when you experience this overheat situation? You may have some ice blocking it during those situations.
Cutting down the strength of the coolant by removing coolant and replacing it with deionized water, as well as adding water wetter, should help somewhat, but it might be negligible. From what I recall, stock coolant in the Yammy sleds is rated for -60 degrees, which is imo, overkill.
I think your Dealer's suggestion in adding the MTX cooler is a sound one, and one that I've done myself and am thankful for it. Perhaps you and your Dealer can come to a middle ground and get a discount on the price of the install, or install it yourself.
Cutting down the strength of the coolant by removing coolant and replacing it with deionized water, as well as adding water wetter, should help somewhat, but it might be negligible. From what I recall, stock coolant in the Yammy sleds is rated for -60 degrees, which is imo, overkill.
I think your Dealer's suggestion in adding the MTX cooler is a sound one, and one that I've done myself and am thankful for it. Perhaps you and your Dealer can come to a middle ground and get a discount on the price of the install, or install it yourself.
Local auto store was out of anifreeze test kits so haven't tested it yet. The tunnel exchanger is clean and no visible ice buildup. I'll also run it on the trailer bed tilted to see what happens.
thanks all !
thanks all !


- Joined
- Nov 1, 2009
- Messages
- 3,564
- Reaction score
- 88
- Points
- 1,483
- Location
- Winnipeg, Manitoba
- Country
- Canada
- Snowmobile
- 2009 Phazer RTX
Try bleeding the system. Do the nytros have a bleed valve with the black cap on it like the phazers?
If yes, take the cap off and put some clear hose on it. something like fish tank air hoses. Put the other end in the reservoir and run the sled until you are happy that there are no bubbles in it. This is how I got the air out of my sleds system.
Make sure there is always coolant in the reservoir or air will be sucked into the lines again.
If yes, take the cap off and put some clear hose on it. something like fish tank air hoses. Put the other end in the reservoir and run the sled until you are happy that there are no bubbles in it. This is how I got the air out of my sleds system.
Make sure there is always coolant in the reservoir or air will be sucked into the lines again.
Zakre
TY 4 Stroke Guru
mewaschuk said:Local auto store was out of anifreeze test kits so haven't tested it yet. The tunnel exchanger is clean and no visible ice buildup. I'll also run it on the trailer bed tilted to see what happens.
thanks all !
If you have not changed the coolant it will be very close to all coolant and no water, yamaha sent them out with a very high percentage so there was no cracked blocks with sleds going way up north to the cold.
I would suggest changing the coolant first thing and trying that.
mach9
TY 4 Stroke Master
I've been having some great luck keeping my nytro running around 160F and sometimes even cooler on the lakes or through fresh snow fields.
I switched to a cooler t-stat.
The stock nytro t-stat opens very late @ 175F I believe.
You can also drill an extra hole or 2 in the stock t-stat.
There is a bypass hole in the stock t-stat already. Just make it bigger and add another hole or even more.
What you get is more coolant running through to the rad sooner before the t-stat opens fully.
But the most important mod I did was put pre-filter vents (round) in the hood right behind the rad.
Right where the tuning fork emblems go.
Pull them off cut a hole and move the emblems to another spot.
Now I have air passing through the rad and out right behind the rad.
Much of hot air is no longer trapped by the fuel tank.
I switched to a cooler t-stat.
The stock nytro t-stat opens very late @ 175F I believe.
You can also drill an extra hole or 2 in the stock t-stat.
There is a bypass hole in the stock t-stat already. Just make it bigger and add another hole or even more.
What you get is more coolant running through to the rad sooner before the t-stat opens fully.
But the most important mod I did was put pre-filter vents (round) in the hood right behind the rad.
Right where the tuning fork emblems go.
Pull them off cut a hole and move the emblems to another spot.
Now I have air passing through the rad and out right behind the rad.
Much of hot air is no longer trapped by the fuel tank.
mach9 said:I've been having some great luck keeping my nytro running around 160F and sometimes even cooler on the lakes or through fresh snow fields.
I switched to a cooler t-stat.
The stock nytro t-stat opens very late @ 175F I believe.
You can also drill an extra hole or 2 in the stock t-stat.
There is a bypass hole in the stock t-stat already. Just make it bigger and add another hole or even more.
What you get is more coolant running through to the rad sooner before the t-stat opens fully.
But the most important mod I did was put pre-filter vents (round) in the hood right behind the rad.
Right where the tuning fork emblems go.
Pull them off cut a hole and move the emblems to another spot.
Now I have air passing through the rad and out right behind the rad.
Much of hot air is no longer trapped by the fuel tank.
Nice! Do you happen to have a part number for the cooler T-stat?? I haven't really looked for it but where is it located?
mach9
TY 4 Stroke Master
I'm using the Viper t-stat, it's somewhere around 120F.
Size is close but not a perfect fit as it's a bit smaller.
I had to use a little high temp RTV to keep things good and tight around the edges.
Pain to get at. You gotta pull the air box out and there it is. RH side under the rad.
Guys that have the K&Ns on already will have no problem with t-stat access.
The t-stat was only part of the puzzle for me.
If you ever let her idle up over 200F it's tough to get it back down again.
(unless you have a lake of powder to spray the exchanger)
I installed an Autometer temp gauge to monitor all the time.
The only way to get temp down while on hard pack trails was the vents and some air speed.
I have the Roset top deck vent, Pre-filter round vents behind the rad, and xxmods vents right behind the shocks.
Size is close but not a perfect fit as it's a bit smaller.
I had to use a little high temp RTV to keep things good and tight around the edges.
Pain to get at. You gotta pull the air box out and there it is. RH side under the rad.
Guys that have the K&Ns on already will have no problem with t-stat access.
The t-stat was only part of the puzzle for me.
If you ever let her idle up over 200F it's tough to get it back down again.
(unless you have a lake of powder to spray the exchanger)
I installed an Autometer temp gauge to monitor all the time.
The only way to get temp down while on hard pack trails was the vents and some air speed.
I have the Roset top deck vent, Pre-filter round vents behind the rad, and xxmods vents right behind the shocks.
Similar threads
- Replies
- 32
- Views
- 3K
-
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.