ZXR250 C Cooling/Radiator Question

[RSrider]

Hey Guys,

Have a few questions. Ever since I bought my 1993 ZXR250 the temperature gauge hasnt really worked as I thought it should.

Basically no matter what the air temp outside or how hard I run the thing it never really gets hotter than just below a 1/4 on the temp gauge (most of the time it barely gets above the very first line). I have noticed that there is a little switch/sensor?? that is threaded into the radiator on the left hand side (you can see it through one of the fairing holes) and it has two gold pins coming out of it which point towards the back of the back. This isnt connected. Could this be my problem, someone told me this was just the fan switch. I have taken the fairing off and I cant see any spare wiring/plug to connect to it, but it clearly should be?

The other thing is that recently I have noticed small amounts of coolant coming from the release hose of the overflow bottle attached to the right rear fairing. What does this mean and is it normal?

Here is a photo of the part I am talking about:

http://images.trademe.co.nz/photoserver/47/71555547_full.jpg

Help appreciated.

Thanks

[Max Preload]

Yes. That (http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Motorbikes/Sports/photos/a-164751737/p-68575442.htm) is the fan switch.

Is there no fan fitted to the bike?

As for the position on the gauge - it doesn't mean a great deal. But I would suspect that there's no thermostat fitted if you spend time in traffic and it doesn't overheat.

No - it's not normal to get coolant flowing out of the reservoir. It's either overfull or there is a problem that needs addressing.

[crashalots]

Hi there, just noticed your thread although its a bit old now I wonder if you have fixed your problem? I also have similar problems with my ZXR250C associated to the thing taking so damn long to heat up! So I've ordered a new thermostat ex-Japan which will be here in a few days. Watch this space...

As for your radiator having no wiring on it, it really should be there somewhere! Best thing is to take off the tank and have a look in where the main loom splits off. There should be a spare plug there somewhere. :sherlock:... :scratch:
If you have water spitting out of your overflow it will be 1 of 2 things.
1) Your radiator and overflow were too full (short term problem)
2) This is the point where the cooling fan is meant to kick in, but it's not wired up! :clap:

Alternatively, something that I have seen before is that people get sick of the fan/thermostat circuit being so unreliable (and they're too cheap arse to take it to the shop) and they just short the wires so the fan runs continuously, this would explain your low temp indication, but not your coolant overflow. :niceone:

[Max Preload]

2) This is the point where the cooling fan is meant to kick in, but it's not wired up! :clap:

The should fan kick in long before it starts boiling and pushing coolant out the overflow from the reservoir.

[RSrider]

Hey mate,

Yup problem sorted. The wiring was stuck up under tha tank as you say, so i've reconnected it and the fans work sweet. As for the temp problem, no it hasnt rectified this.

However, after speaking to a friend how has 3 ZXR250 c's and races them as well, he says that none of his ever really get above the first or second red line on the temp gauge, more than often it is sitting just above the blue 'cold' mark. Apparently the cooling systems on these bikes are over-efficient for the size of the motor etc.

My temp gauge definitely works, it just doesnt really get as hot as I would have thought it should. I.E in a car it sits in the centre between cold and hot. Send me a PM when you've had your thermostat fitted and let me know if it fixes it.

Thanks

[PHATVW]

Hey RSrider, I've got the same problem too! Did you figure out the coolant problem?

Check my thread for more details: http://www.kiwibiker.co.nz/forums/showthread.php?t=83841

How many kms has your one done? Mine's done 23,000kms, due for a service soon :oi-grr: