Radiator fan not working

[CB ARGH]

Yet again, another problem.

Started it up and let it warm so I could change the oil. I noticed that the radiator fan wasn't going so I tested it out by letting it keep running until it popped on. Five minuites later, still no fan movement, another five minuites later, no fan movement, bike making weird revvings, so I turn it off. The bike was far too hot, the fan should've turned on ages ago.

Can somebody please point me in the right direction as to how I can determine what is wrong?

Cheers,

STEVEN

[koba]

Yet again, another problem.

Started it up and let it warm so I could change the oil. I noticed that the radiator fan wasn't going so I tested it out by letting it keep running until it popped on. Five minuites later, still no fan movement, another five minuites later, no fan movement, bike making weird revvings, so I turn it off. The bike was far too hot, the fan should've turned on ages ago.

Can somebody please point me in the right direction as to how I can determine what is wrong?

Cheers,

STEVEN

Make sure the fan runs with 12v applied to it.
Try not to cut fingers off
The fan should have a temperature sender somwhere, maybe in the thermostat housing, maybe in the radiator.
It will also prob have a sensor for the guage or light if it has one.
Figure out which it which, use a multimeter to see if it switches at hi temp, if it doesn't replace it.
If it all looks nasty and complicated or the sensor is too expensive a quick fix can usually be made by wiring a switch into the fan curcuit so you have control of when its on or off, this requres attention to be paid to the temp by the rider...

[CB ARGH]

If it all looks nasty and complicated or the sensor is too expensive a quick fix can usually be made by wiring a switch into the fan curcuit so you have control of when its on or off, this requres attention to be paid to the temp by the rider...

Yes I might give this idea a go. Cheers

[Tony.OK]

Check your fuses, when I had my VTR1000 it had a habit of blowing the fan fuse for a while, may have been cheep n nasty fuses.

[Motig]

Spose the fan does turn if you move it with finger ? I know its a different bike and layout but the early VFR 800s would occasionaly get a stone jammed in the fan/housing.

[CB ARGH]

Just checked the fuse, it had blown. Replaced it.

Will put it all back together tonight after work, and give it a go again...

Once the oil is put back in though haha!

Thanks for your help guys!

[CookMySock]

Just checked the fuse, it had blown. Replaced it.

Better have a quick nosey why it blowed. Check around the loom to see if a wire is touching the frame somewhere - it will rub through here and short out. Carry a spare fuse for a while.

BTW, you can prolly put a slightly larger fuse in there - just make sure there is not a legit fault first. The fuse is just there to protect the wiring loom should something draw way too much current and take the loom out in a ball of fire. 8-9 amps continuous will eventually take a 10A fuse out - replace with 15A provided the wiring will handle the 15A and blow the fuse rather than fry the wiring.

Steve

[scumdog]

Yet again, another problem.

Started it up and let it warm so I could change the oil. I noticed that the radiator fan wasn't going so I tested it out by letting it keep running until it popped on. Five minuites later, still no fan movement, another five minuites later, no fan movement, bike making weird revvings, so I turn it off. The bike was far too hot, the fan should've turned on ages ago.

Can somebody please point me in the right direction as to how I can determine what is wrong?

Cheers,

STEVEN

I see your problem - your bike has a radiator and a fan, utter frivolities, motorbikes shouldn't have them!!

Seriously, check these (sorry if others have already posted this):

Fuse.

Wiring IS connected to fan AND the thermostatic switch ('sender').

Try disconnecting the wires from the fan and (carefully) hook up some wires from a bettery to the fan to see if it actually goes.

Not sure how good for your bikes 'lectrics this would be BUT I would diconnect the two wires from the thermostatic switch and using the same wires for the above check I would carefull by-pass the switch to see if it made the fan go on.
Good luck.

[motorbyclist]

my late NC30 had a similar problem where the thermal switch failed.

replaced it and it died again shortly afterwards, so i bypassed it with a switch all nicely done, leaving original wires intact incase i decided to replace it again

of course, working fuses would help

[Bren]

My bike has a similar setup...the fan is turned on by a switch hidden under the fairing very tidy like.

[Conquiztador]

The termal switch is in the radiator at the bottom where the water goes to the pump/hoses goes back to motor.

Logic here is that as the water enters the radiator hot at the top it will then cool down as it passes the radiator. But if it is still too hot when going back in to motor the thermal switch will sense this and turn on the fan to cool the water even more. Normally happens when a hot day and/or in city traffic stopping/starting.

This is why when you have a blown head gasket and the water gets really hot, the fan might still not turn on as the radiator is doing a too good job. Then when you stop you suddenly have a surge of boiling water coming out the expansion chamber.