How long does the radiator fan stay on? - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 5 (permalink) Old 09-05-2011, 03:34 PM Thread Starter
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How long does the radiator fan stay on?

I just purchased an '86 Vulcan 750... love it!... but has a couple of issues. The fan is kicking on, and making a noise that sounds like an electrical 'buzzing', and keeps going for quite a while. I actually disconnected it to stop it so it wouldn't drain the battery. The temperature gauge does reflect the engine warming up but never gets close to the red zone. Does anyone know if the fan automatically starts up and runs for a certain period of time after the bike is turned off? Does anyone know how hot the engine is supposed to get? Has anyone had their fan make that sound (almost like a buzzing)? How do you fix that? Thank you! Todd
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post #2 of 5 (permalink) Old 09-05-2011, 03:46 PM
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Hi Todd. The fan and sensor are wired outside of the ignition switch so it's normal for the fan to stay on or even come on after you shut the engine off. How long depends on the temperature that the sensor is reading. Mine after a good ride on a hot day may stay on for up to a minute. If yours stays on longer you may need a new temp sensor. The noise could be as simple as a loose mount on the fan housing causing it to vibrate, or a chipped / broken fan blade throwing it out of balance.
As far as normal operating temp, most report the needle sitting just to the left of the thermometer symbol and at most slightly right if it. That's where my bike runs as well but in heavy traffic/hot weather it's gon to between the symbol and the red zone but not more than that. Hope this helps you .


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post #3 of 5 (permalink) Old 09-05-2011, 05:30 PM
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My bike on a hot day never runs hotter than half way on the temp scale. When I shut off the fan keeps or starts running for about 15 seconds. I don't recall it ever running much longer than that. I agree with Dave, it's either a loose mount or broken blade that's making the noise. My fan makes a low level hum sound.

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post #4 of 5 (permalink) Old 09-05-2011, 07:33 PM Thread Starter
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Thanks Dave! Appreciate it!
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post #5 of 5 (permalink) Old 09-05-2011, 07:34 PM Thread Starter
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Thank you!
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coolant , fan , radiator , sensor

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