running hot or ?

[rdssdi]

My +2 continues to "run hot". To be more accurate, the gauge indicates a temperature range from 90 deg C to 115 dec C. It appears that the gauge may be inaccurate as I assume somewhere within that temperature range I would be seeing some signs of overheating. In fact I have had a gauge reading in excess of 100 deg C and the fan sensor has not turned the fan on which is set to go on at 200 deg F (92 deg C approx.).

The gauge is getting 10 volts, the temp sender and gauge are new. The gauge should be at mid scale with 67 ohms. I used resistors to get that value and the gauge went to mid scale. Either the gauge is wrong or the car is running hot.

The gauge reads 50 - 90 - 140 deg C. I have a new sender which is a replacement for the original Smiths.

Any suggestions?

I have attached a photo of the car. I have since added two Talbot mirrors on the doors.
Bob

[john.p.clegg]

Bob

You've tested the gauge by using resistors,with a good 10v supply and it's correct,your fan ( 92 ) doesn't cut in which seems to say that the engine is not running hot,so that leaves the sender which seems not to match the gauge or is faulty...The sure way to find out is to fix a central heating thermometer to the thermostat housing and note the real temperature...you could then try adding resistors in-line with the sender till they match?

John

[rdssdi]

It is my understanding that the boiling point of water goes up 4 degrees (F) with each pound of pressure. Therefore with a 10 pound radiator cap I can expect 40 deg F increase in boiling point. As this is for water, the addition of antifreeze should increase that boiling point. So if my car is indeed running as high as 115 deg C (239 F) it is near boiling over but not hot enough to boil. i.e. boiling point water 212 deg F plus 40 deg F.

The remaining unknown is the custom alloy radiator that I purchased from Mac's Radiator. As the electric fan air flow seems to "bounce off" the radiator face is the fin spacing too tight?

Bob