Overheating issue no fan

[Bansh]

I have a 2005 Busa,
Only when I'm stuck in traffic I overheat. Usually when temps reach midway on the temp guage the fan kicks on.
The fan is not comming on and the temp goes through the roof!

I've put 12vdc to the fan and it works fine. I flushed the radiator system and replacd is new coolant. That seemed to work until yesterday; caught in traffic and overheated, again fan NOT on!

Any help would be greatly appreciated!

I am about to direct wire this fan so it's always on!

TIA

 

[dadofthree]

I no longer have the manuals for the Gen I, but from memory you might have a fuse or switch issue. From memory there's simple directions for troubleshooting this problem. Running the fan continously will cause problems with your battery and affect the performance of the bike because of motor temp issues. Regardless of those issues I would suggest you troubleshoot the system and get it working as designed.

Good Luck on the fix

 

[dadofthree]

Try this link :

https://www.hayabusa.org/forum/maintenance-do-yourself/24284-permanent-shop-manual-hosting.html

 

[DropBusa]

Far fetched, but check your head gasket.

 

[Bansh]

changed coolant, fuses are good. I think it might be a relay?
I tap on it fan comes on. Relay = $160.00! Is there an easier way to troubleshoot the relay?

 

[dadofthree]

changed coolant, fuses are good. I think it might be a relay?
I tap on it fan comes on. Relay = $160.00! Is there an easier way to troubleshoot the relay?

If you have the electrical schematic in the manual and a VOM just make sure the voltage is on the relay coil and that the voltage to the motor is there. It sounds like the relay. I've never looked at the relay, if there's a way of jumping it out just use a set of keys or needle nose pliers. But from reading your comment it's the relay. Tapping it shouldn't make it operate. If it plugs into a base make sure the relay is secure in the base.

 

[Commuta_Busa]

sounds like a problem with the actual fan. If you've got to tap it for it to work then it sounds like everything else in the system is fine but the fan itself.

 

[Bansh]

I tap on the relay and the fan comes on!
Quick note: battery tender has 12vdc on them. I hooked the tender directly to the fan and the fan works solid.

I'm not sure if it's the base, or the relay at this point?

 

[Schism]

i had this problem years ago on my 01' you have to sit on the bike with the cap off the radiator and sway left to right while running it for several minutes. the "burping" process is crucial when flushing the radiator. i went ahead and swapped out my thermostat which was around $20 and that cured all. the thermo. is located directly behind the motor under your front seat ,so to speak. you will see it when you prop the tank and it's about the size of a "golf ball". good luck!

 

[NCpanther01]

i had this problem years ago on my 01' you have to sit on the bike with the cap off the radiator and sway left to right while running it for several minutes. the "burping" process is crucial when flushing the radiator. i went ahead and swapped out my thermostat which was around $20 and that cured all. the thermo. is located directly behind the motor under your front seat ,so to speak. you will see it when you prop the tank and it's about the size of a "golf ball". good luck!

+1 Burp the system first...JM2C

 

[Bansh]

Just bought some "Engine Ice" off to flush the system and Burp that bad boy!

Thanks for the info!

 

[Mr Bogus]

if "tapping" the relay makes it start, then all the coolant and burping in the world is a waste of time.. pull the relay and make sure there is not a bunch of corrosion on the legs of the relay..

also, make sure that the fan temp sensor is connected and working correctly.. (jump the wires) if the sensor is bad, it could be providing a faulty ground circuit and when you whack the relay, it gives it just enough help to work (weak magnetic field to pull contact spring down) could also be a bad ground or low voltage to the trigger circuit.. a voltmeter is needed here..

 

[Bansh]

When I poped the radiator cap I was about an inch low on coolant! The top of the radiator was burned coolant!
Flushed system, added "Engine ice" burped system as stated in manual. Fan came on @ midpoint like it use to. Let bike cool down(hour). added even more ICE to the radiator. Temp never get above mid point! Fan cycles on & off like clock work!

Rode around block (shake things up), let cool another hour. Radiator is full, no air!

I think she's fixed!

Thanks for all your help!

 

[motomc1]

Congrats. I can't wait to get mine up and running. i had to buy another fan myself.