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Discussion Starter #1
My electric fan will not turn off - had to disconnect the battery. Can any one help with what could be wrong
 

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Heat sensor/switch I would say. There's a procedure for how to test it here on the forum and in the service manual.
 

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I would say it's either the temperature sensor, or the relay in the junction box. At least it's not the $400 fan motor, since it still runs. Jerry.
 

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Old Truck Junkie
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My electric fan will not turn off - had to disconnect the battery. Can any one help with what could be wrong
You do know that some times the fan will run for a few seconds after shut down. Any longer than that there is a problem.
 

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Simple Solutions
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I would say it's either the temperature sensor, or the relay in the junction box. At least it's not the $400 fan motor, since it still runs. Jerry.
400 dollar fan motor it looks like a standard 12 v elec fan to me ..been known to be wrong but i bet u could get one pretty cheap


you could also wire an inline toggle switch to shut it off when ya stop ridin .... just remember to flip it on befor u get stuck in trafficc and u should be good to go
 

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Linkmeister Supreme
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The first thing I would do is tap the heat sensor switch a few times with a screwdriver handle, or the like. The switch is down on the lower left side of the radiator, with a wire connector attached. Then tap the junction box, where the fuses are, with the screwdriver. Apparently there is a relay inside the JB that can stick, and may just need to be jarred a few times to unstick the contacts.

This is from the verses:
Radiator/Cooling Fan not shutting off

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Quote:
Q: Has anyone else come across the radiator fan NOT shutting off? On Tuesday I went out in the morning to ride and my battery was wasted.
What I noticed though was the radiator fan was still running. Usually
it runs after I shut the bike off but will usually stop running after
a few seconds. The problem now is it won't stop running so I had to
unplug its power source. I am now plugging it in when I go out to
ride but disconnecting it when I get to where I'm going.

Anyone got any idea what that might be or anyone come across this
issue? Bad thermostat?

By the way, the bike is not overheating and no overflowing of any
fluids; all coolant levels are ok.


A: I just had the same problem on my 95 750 i took mine to toe kawasaki shop the checked it out a the circuit box was bad. they fixed it it works fine now. Bill

A: Hey, had this very same problem... first problem I had with my VN750. On mine, it was a fan control relay sticking. sometimes in an old relay, or one that hasn't come on in a long time, when it DOES turn on after so long... it sticks in the "on" position. next time it does it, or if it does it next time you start it up, take the seat off and look on back of the battery box for the junction box. I give it a whack with my leatherman, and voila, the relay tripped back the other way. I had to do that a few times... now and then for a week or two, after I bought my bike, then it quit doing it.
After the relay had tripped back and for several times it probably cleaned itself off. note: The bike had been stored for the winter just previous to me buying it, hence the long time without the relay being tripped. Other times the contacts inside the relay just plain arc for whatever reason, andthe same rules apply... whack it now and then and it might straighten up, or if it doesn't you at least know how to shut it off til you can get a new junction box installed. Scott 1992 VN750 Sylvia


Quote:
Q: I have had a suspicion that my radiator cooling fan has not been coming on of late. Usually, I shut off my bike after a ride, and then back it into its parking space in front of my truck in the garage, but to test my suspicion, I left it running, knowing that normally the fan would come on before I got it parked. Sure enough, no fan.... so, I got out a screw driver and lightly tapped the housing around the fan a couple times... viola... the fan came on. Was it just stuck in a particular place in its rotation? Did I jiggle the sensor enough to make it work... this time? Is my problem solved? I guess I won't know that until my next ride, but any suggestions from anybody, or comparing notes from others who have experienced the same thing would be appreciated. Thanks, Jangles

A: I had this happen before.. Turned out it was a crudded up connector. We pulled it apart, cleaned it up and repacked with dielectric grease and it has been running fine every since. The connectors especially in the front of the bike seem to pick up a lot of road grime even if they are tucked back. Ended up being a cheaper fix then replacing the fan and sensors *S* There is a way to check the fan by jumping it but not sure of the exacts.. hopefully someone else will fill in that part.

A: you say the fan housing, I would dare suspect the motor itself having a bad brush, or a stuck one. tapping it may have jarred it loose. having same trouble with wife's starter motor, cleaned the brush holders and hoping for the best. would get another starter, but they are quite hard to come by used and cheap, so far still looking. not sure how hard it is to get fan motor apart....other idea is did you jiggle the sensor wire a little and it was just a dirty contact? also check the connector the fan operates by also. testing the fan: can be tested for brush problems by removing it and connecting it to a low voltage source, like 6 volts. momentarily run motor to make sure it will not be dangerous to hold the blades (not running too strong) grab blades firmly, or use a pencil or something to hold them with. apply low voltage, walk blades around...if it finds a spot where it isn't pulling your hand, you have a bad motor. don't keep motor in same place over a second or two, or it may over-heat. Thanks, just my 2 cents....... Beavis
 

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Discussion Starter #7
Thanks to all who replied. How do you disconnect the fan. Is there a switch or connection that can be disconnected so the fan is shut down
 

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Linkmeister Supreme
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Yes, just pull the wire off the heat sensor switch down on the rad.
 

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You can also pull the wires off the fan motor itself.
I was wrong about the price of the fan. 59502 fan assembly-$460.57. Talk about a rip off. I believe this is the same fan that the first generation KLR650 used, and back when I had one of those, and belonged to a KLR650 forum, someone had figured out a much cheaper way of replacing it. You can't just use any 12V fan, the factory fan spins at about 50,000 RPM, way faster than any ordinary fan would. Jerry.
 

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Simple Solutions
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You can also pull the wires off the fan motor itself.
I was wrong about the price of the fan. 59502 fan assembly-$460.57. Talk about a rip off. I believe this is the same fan that the first generation KLR650 used, and back when I had one of those, and belonged to a KLR650 forum, someone had figured out a much cheaper way of replacing it. You can't just use any 12V fan, the factory fan spins at about 50,000 RPM, way faster than any ordinary fan would. Jerry.
12v fans can be purchaed at many rps there is only so much draw that could be pulled through those little wires ...

when fan shopping i wouldnt go pic up a model car motor but most interior and exterior car motors will spin at a high enough rpms for there designs are for the same purposes move a large volume of air ...
 

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My Clymer manual does not list the normal amp draw of the fan motor, but I would suspect it is quite high for the size of the motor. Kind of like a starter motor, the fan motor is not designed to run all the time, it would probably burn up, or would burn up the relay in the junction box. I was thinking about just hooking it to a manual switch, so I could run it more in stop and go traffic, but decided against it for that reason. Jerry.
 

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My electric fan will not turn off - had to disconnect the battery. Can any one help with what could be wrong
I reckon it's the coolant temp switch on the lower left side of the rad. When I bought 'Sweep' last year the switch on mine was broken and the PO had wired a switch into it so that he could turn it off & on manually. OK if you keep your eye on the temp gauge and/or remember to turn it off!

If you pull the wire off the switch and it stops, there's your fault. Just get another one. The switch is common to a lot of other bikes, I got mine from Ebay US, shipped over here for $25.00.
 

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Linkmeister Supreme
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Glad to hear the quick, no cost fix worked. I hope it keeps on working too.
 

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Linkmeister Supreme
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I reckon it's the coolant temp switch on the lower left side of the rad. When I bought 'Sweep' last year the switch on mine was broken and the PO had wired a switch into it so that he could turn it off & on manually. OK if you keep your eye on the temp gauge and/or remember to turn it off!

If you pull the wire off the switch and it stops, there's your fault. Just get another one. The switch is common to a lot of other bikes, I got mine from Ebay US, shipped over here for $25.00.
Martin, I think you have over simplified the diagnosis. If you pull the wire off the sensor switch, or a manual switch for that matter, good or faulty, the fan WILL stop.

You can eliminate the fan motor as faulty in a case where it doesn`t run, by applying 12 volts to it with a jumper wire. If it works then the problem is a faulty switch or wire or connector.

The only sure way to know the switch is at fault is to test it for continuity, or tap it, and the relay, as Revelation did, and as a result the fan motor shut off.
 

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Linkmeister Supreme
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You can also pull the wires off the fan motor itself.
I was wrong about the price of the fan. 59502 fan assembly-$460.57. Talk about a rip off. I believe this is the same fan that the first generation KLR650 used, and back when I had one of those, and belonged to a KLR650 forum, someone had figured out a much cheaper way of replacing it. You can't just use any 12V fan, the factory fan spins at about 50,000 RPM, way faster than any ordinary fan would. Jerry.
Jerry is that number 50,000 RPM correct, or a typo? 5,000 RPM seems reasonable, but 50K RPM just seems over the top to me. :wow:
 

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Martin, I think you have over simplified the diagnosis. If you pull the wire off the sensor switch, or a manual switch for that matter, good or faulty, the fan WILL stop.

You can eliminate the fan motor as faulty in a case where it doesn`t run, by applying 12 volts to it with a jumper wire. If it works then the problem is a faulty switch or wire or connector.

The only sure way to know the switch is at fault is to test it for continuity, or tap it, and the relay, as Revelation did, and as a result the fan motor shut off.
Gordon, I am an inherently simple person!!!
 

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Actually, the closest I can come based on what information I can find, it should be closer to 35,000 RPM. That little fan moves a lot of air for it's size. Jerry.
 
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