Coolant temperature sensor.

[Andy]

Gidday people. I need to check out my coolant sensor but can I see ? NO I CAN'T. I believe it's at the front left of the head but ??? The fan works under test but the coolant will boil without the fan firing up.Any info or accurate location pointers would be great. Thanks Andy.

 

[warp9.9]

Right by the thermostat housing int he front left of the motor like you suspected. As you look at the thermostat housing it is at about the 6 O'clock position. I am not sure why your boiling over but maybe you just changed the coolant and need to bleed the air out of the block. There is a bleeder bolt at about 12 O'clock on top of the thermostat housing. If the Head casting is good. if not like my 06 there is a pretty bolt holding/plugging nothing on my Head

 

[Andy]

Thanks living legend I'll have another look tonight armed with that info. Tried the 12 minute tune and the tank just overflowed before the fan came on. Tested the fan with tune ecu and it was good. Put it down to either the sender or the fan temp being too high somehow. The tune ecu phone app doesn't access the setting or adjustment it seems. Have changed the coolant and thought I'd bled it properly. Cheers for that.

 

[warp9.9]

Thanks living legend I'll have another look tonight armed with that info. Tried the 12 minute tune and the tank just overflowed before the fan came on. Tested the fan with tune ecu and it was good. Put it down to either the sender or the fan temp being too high somehow. The tune ecu phone app doesn't access the setting or adjustment it seems. Have changed the coolant and thought I'd bled it properly. Cheers for that.

It could just be a bad radiator cap. If it won't hold the pressure the coolant will boil at a lower temperature pushing into the overflow.

 

[Andy]

It could just be a bad radiator cap. If it won't hold the pressure the coolant will boil at a lower temperature pushing into the overflow.

Wondering if the cap off my yamaha will fit as a test. How different can they be :-D Try later.

 

[keno351]

could be a stuffed thermostat

 

[warp9.9]

I would have the radiator cap checked first. Just a observation from what I have noticed over the years on theses sites and I do not remember running into a stuff thermostat yet. I thought my 06 had one but after the wrestling match to change it without pulling the oil tank or any other major component (which it can be done) I found out my cap was crap.

The good thing is either one is not expensive!!!!!!!!!!!!!

 

[Andy]

I would have the radiator cap checked first. Just a observation from what I have noticed over the years on theses sites and I do not remember running into a stuff thermostat yet. I thought my 06 had one but after the wrestling match to change it without pulling the oil tank or any other major component (which it can be done) I found out my cap was crap.

The good thing is either one is not expensive!!!!!!!!!!!!!

I'm gunna grab one tomorrow if there's one in stock. Not sure how to test the existing cap. Does seem to b an issue. It's an '06 with only 50,000 km but nothin lasts forever :-D

 

[warp9.9]

I'm gunna grab one tomorrow if there's one in stock. Not sure how to test the existing cap. Does seem to b an issue. It's an '06 with only 50,000 km but nothin lasts forever :-D

I have seen guys who thought theirs was bad and it turned out not to have the lock screw in the cap. It vibrated enough to rotate and release itself some once tightened it up it went away. Check your to see if it has the lock screw on it. A pressure test would probably have to be done at a radiator shop due to the various sizes of caps now days.

here is a shot of the tester on a cap and the system. Same theory if you just have a radiator with a cap on it when testing the system.

 

[TURBO200R4]

a thermal gun works great when diagnosing these kind of problems.
you can put the laser on any area of the eng or rad to get the temp.
also if you have to much water in the over flow tank it will come out when it gets hot.