When should I turn on and/or turn off the valve that lets the heated coolant run through the carb bodies? I know this feature is to keep the carbs from freezing up, but a riding buddy told me to leave it off unless I was riding in super-cold temps (like -20). What’s your experience?
I agree that the heated carb valves should be normally â€œoffâ€ and turned on when needed. There are two conditions that I have experienced freezing of the carbs; very cold temps when the snow is so fine and powdery that it gets past the intake filter (why you need a pre-filter) and when the humidity is very high, at most any temperature close to freezing. This is why Ski-Doo suggests to open the valve when riding in high humidity conditions.
Usually when the carbs start to get sticky you can catch it before the sled will die on you (usually due to the electronic safety system sensing a problem and kicking in). Get that valve open and get them carbs warmed up! How about if you don’t have the heated valve? Often, the heat of the engine will warm the carbs up to thaw the ice while sitting there for a few minutes, then you can add a bottle of isopropyl to the gas and in a matter of a couple of miles the iso starts to do its thing. Even with the heated carbs, you have to get the water out of the system, so using iso is still a good idea, even with heated carbs. I rarely leave for a ride without a bottle.