Cooling fan not coming on?

[chief]

Well you do need to determine if the engine is overheating. You can check the thermostat as indicated. That will eliminate that as a problem. You have to start someplace.

[ski.dive]

Remember,  I got this 1999  1500 Drifter on Monday. This Drifter sat outdoors uncovered for about 2 years, this is why all the issues, now I have two 1500 Drifters a 1999 & 2000.

I had the bike idle outside for 30 minutes after I changed the oil [milky oil], in the 30 minutes it sat there idling the cooling fan never came on once, on my other Drifter the fan comes on after 10 minutes of idling?  Outdoor Temp. was around 74.

*This is also, when I heard the gas cap hissing and saw the gasoline bubbling in the tank.

I really do not know what the engine temp. was, so I do not know if the fan should have com on after 30 minutes of idling.

[chief]

If the engine isn't really getting hot, you've eliminated a bunch of potential causes and you can likely concentrate on the fan controls and temp sensors.

But if your engine is truly getting hot there are a number of potential causes - clutch, brakes, low oil, fuel mixture, plugs, engine deposits, water pump, etc.

The thermostat opens and closes to keep the coolant within operating range. The thermostat starts opening at 136-144F (58-62C) and is fully open at about 167F (75C).

The fan doesn't come on until the coolant reaches between 212 and 230F(100-110C) and it will go off again at between 207-217(97-103C).

So, if your engine really is at 212 or so when the fan comes on, then you know the fan switches etc are working fine... but the thermostat may be faulty.

You can test the thermostat by removing it and suspending it in a clear pot of water, with a good thermometer suspended next to it. Increase the heat until you see the valve start opening - check the temperature... increase further until it is fully opened (about 8mm - I think)... check that temp...

If its within range, then you have something else causing the high temp problem, and there are a number of things that can do that.

[ski.dive]

I noticed my 1500 Drifter IS RUNNING HOT AND THE COOLING FAN IS NOT COMING ON.

I checked the FAN FUSE , it's GOOD.

What do I need to check, to get the fan to work?