1972 240z Temperature rising on idle while traffic and stop lights

[jalexquijano]

I am really worried about the Reading on my temperature gauge as it is raising to 3/4 while on idle during this last weekend. The weather on Saturday was 32°C and lot of heat from the pavement. I am driving the car with no thermostat on and it should lower the needle to 1/2. I tried spinning the fan clutch and it does move at least 1/4 of the complete spin. Will i risk the engine at this Reading or could the gauge be damaged? The car has Brand new 5 quarters of oil and new oil filter and it reads what you see here! Once the car starts moving away from traffic the temperature lowers to half!

[Dreco]

you should use a thermostat to restrict the flow. Do you have a fan shroud?

[jalexquijano]

No fan shroud! My father had a Daihatsu Charade which had one carburetor and removed the thermostat. The car never overheated. Could the Gauge be damaged? Is the Reading of the oil ok?

[olzed]

32C is a pretty hot day.

My 72 does exactly the same during the hot summer months, but in winter it is OK. Try not to idle in traffic.

I fitted an electric fan to mine in front of the radiator, which has helped somewhat. I flick it on when sitting in traffic.

Edited April 1, 2014 by olzed

[Stanley]

With the engine running and still cool you can take the radiator cap off and check if the coolant is swirling around in there. With no thermostat it should be some real rapids.

Otherwise, maybe water pump problem or partially plugged radiator. Also test the fan clutch, if you didn't do that already.

If you drive in a lower gear in slow traffic it will keep the fan speed up.

[Dreco]

No fan shroud! My father had a Daihatsu Charade which had one carburetor and removed the thermostat. The car never overheated. Could the Gauge be damaged? Is the Reading of the oil ok?

a fan shroud will help the fan pull air through the radiator when sitting. Does it run cooler after you start going (does the gauge move back down)? without a thermostat, your car will (should) take too long to get to operating temp. I live in the texas heat and ran a 160 degree thermostat with a 4 row radiator and fan shroud.. never had a problem..