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Discussion Starter · #1 ·
can anyone answer help me with my over heating problems
my bird doesn't have a fan switch that goes into the radiator
i have order up the temperature sensor that fits on the water pump (temp gauge has seen 124c) f1 light comes on
three pin plug on the sensor
does this control the fan temp as well as the displayed temp
 

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Yes it give you the temp reading and also ecm to turn the fan on.
What symptoms do you have for your temp going nuts?
Easyest ones are, Low coolant level in expansion tank, rad cap faulty, low coolant in rad, crap build up on coolant hose mounts causing a very very small sweeps, oh and stuck thermostat. I have put my own bypass switch in, just incase, and by doing this it doesnt effect normal operation of fan turning on temp, it just gives me peace of mind knowing I can if needed.
 

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Seems like almost all coolant is now premixed. This presents a small problem.

You drain the old fluid and then lets say, flush the system with distilled/deionized water to get all the old stuff out. Now time to refill, but as there is anywhere from a small fraction, to 50% (depending on vehicle) of undrainable water still in there, then your premix will be diluted. This will reduce boil over and freezing protection.
 

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Burn me at the stake lol, but I have never bothered flushing a coolant system, I just make sure I change it every time I buy a new bike to me and just change coolant every 2 years.
The only time my engines have been coolant free is on a rebuild.
Not had a problem.
That being said though if i bought one with pond water and algae in it, then yeah i would have to flush and clean, and also undo the cylinder coolant drain bolt to make sure.
 

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Yes it give you the temp reading and also ecm to turn the fan on.
What symptoms do you have for your temp going nuts?
Easyest ones are, Low coolant level in expansion tank, rad cap faulty, low coolant in rad, crap build up on coolant hose mounts causing a very very small sweeps, oh and stuck thermostat. I have put my own bypass switch in, just incase, and by doing this it doesnt effect normal operation of fan turning on temp, it just gives me peace of mind knowing I can if needed.
Ok, so why is your BB hitting 124C...?

If the thermostat is stuck closed you can verify by idling the bike up to temp from cold. As the temp gauge hits 84c it should drop back to 79c before heading up to 101c where the fan should start and bring the temp back down to 94c.

What does your FI Bird do when you let it idle up to temp! Does it just go from zero to 124c with no little back step at 84c (where the thermostat should open fully)?

Changing coolant is a simple job, but it can cause problems if not done correctly - air bubbles will cause overheating if not bled properly. Also, a lot of old coolant or flush water is trapped in the lower left of the rad below the hose from the coolant pump (I syphon that out). The cylinder head must be drained too.

It's a good idea to buy a new rad cap unless you replaced it recently.....the cheap car like ones work just as well as the 3x more expensive Honda caps (I have one on my 05).

Did you change the coolant prior to the overheating issue, or, what happened to the bird between running ok and overheating?

This info will help us to zero in on the problem.

;)
 
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Discussion Starter · #8 ·
This problem all started because the lower mount bracket became detached form the radiator ,2001 inj model

Ordered a Chinese copy rad
fitted the new radiator, took care in bleeding the system, used green anti-freeze, bike temp running high, took the radiator to local company to test water flow and core temp results, same amount of cores, but less efficient than stock
refitted radiator, same reading on temp gauge

ordered up a new temp sensor, plugged it in to my amazement 106c without fitting just plugged in
polished old sensor fitted it back on running temp on tick over is 107c max, fan kicks in at 104c but the cold side of the radiator is where the temp sensor was fitted on older models, regardless of the temp reading is ok to touch

The bike before all this, ticking over 104c with fan in and out, riding temp 86 c
my conclusion
radiator runs warmer than stock
wrong / faulty temp sensor
i have 100+ mile run to attend tonight, going to take a chance that everything regardless of temp reading
 

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Just make sure when you take out and put back the temp sensor in, you put some instant gasket on the threads, I made this mistake, even with a new crush washer after a good few miles the coolant was trying to ever so slightly leak up through the threads.
I changed my temp sensor rad cap and thermostat when I got mine, and also cleaned off where all the coolant hose attached, I think the PO of mine was chasing the slight weep before selling.
I also fitted a fan switch, just incase, but what I did find is after fitting a manual switch my rad fan is spot on coming on at 101c going off at 93c I think it was.
I think I must have helped earth it with fitting a switch.
 

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All I've done to my 98 in 45k miles (Knocking hard on wood) is Engine Ice in radiator and Mobil one synthetic every year in the fall. Pricey compared to most but been worth it so far. She runs hot as all confirm.
 
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