I have recently replaced the 2nd thermostatic switch, fan still doesn't come on. I put my own switch in but I want to kick in when it's supposed to. Only thing left to try is the thermostat. Any ideas?

 

there is only one switch that turns the fan on, the other switch there near it just runs the red dashlight on and its a seperate circuit. the coolant thermostat under the housing is mechanical just like a car's and it has no control over the fan either.

by unplugging the two wires that go into the fan switch and connecting them together with a homemade jumper, the fan should come on. if it doesn't, check for presence of voltage getting to the fan - the fan cord plugs into a connector at the wiring harness on the left side of the frame, near where the CDI plugs in. unplug it there and put a meter on it. if there is voltage there but the fan doesn't run when plugged in, the fan is dead. if there is no voltage there then when the fan switch is tripped on or jumpered as described, then there is a wiring problem.

hey, nice pics by the way, on your photopage!

 

Hightower,

Thanks for the comments on the pics. I wish I can go to SL this year. I got a MUCH better camera this time (8 Megapixels) and takes MUCH longer videos.

Anyway witha jumper and a switch which I have installed... it does turn on. It just doesn't seem to do it on it's own. I'll run a voltage on it see what gives. The DS is starting to show it's age.

 

if you have an ohmmeter or DVM you can put the thermo switch in boiling water, wait a few minutes then measure the resistance it should be near zero.

 

There is also a 15 amp fuse located in front of the airbox (engine side) on the sides where all the wires are. The fuses are located in the water proof connectors. There are fuses on both sides but check the 15 amp one (gear shift side)....I believe the other is a 25 amp.

JMiller

 

If the fan runs with a jumper across the thermostat terminals it won't be the fuse, the problem has to be in the switch(themostat). I did have a fan that would stick at one spot, I believe the start windings were damaged. if you stuck a screw driver or some other device in the fan blade and push started it, it would run until it shut back off, sometimes it worked, sometimes it wouldn't.
You could be running cool and not needing the fan. Does motor feel very hot? Not sure if the temp could be checked somehow. If jetted right, I've have seen these where the fan very seldom turned on, than again, I've seen them where the fan never turn off.
If you have installed two new switches and it still won't run yet it is very hot feeling which will effect your power, maybe the water system somehow is air locked. If water is not flowing thru the Cylinder the thermostat would not operate properly, of course your top end would not last long and if you have riding for awhile now with this problem I would think you would have bigger issues. Hopefully you just have a bike that runs cool....

Good Luck

 

i just run mine off the switch seems to stay pretty cool that way. then again racing 30 -40 times in a row makes for a hard day.

 

DaSandBomb I think has given me a hint here. It seems as if my DS is leaking a small amount of coolant. The resivoir seems full but I didn't check the radiator. Tomorrow I'm hitting the track with my Stage III buddy and we are going closer to the afternoon. Before I go I need to install a skid plate and I will check the coolant. Perhaps there wasn't enough coolant to trigger it.

If I am leaking coolant it can be either a faulty hose or a gasket leak. The gaskets are copper and were part of my kit from TVI.

 

maybe the thermostat is stuck open. allowing water to flow all the time would keep the switch cool enough to stay open. and fan off.

 

Make sure to check the pesty Water Pumps seals if you suspect a coolant leak. If you keep the weep hole open it will drip out the lower front of the left case. If the weep hole is plugged, check for water in your oil[img]i/expressions/face-icon-small-sad.gif[/img]