[flyrod3435]

I am having a some strange issues going on with my temp gage, With the engine running the temp gage slowly rises until its pegged. i have replaced the thermostate, and had the radiator recored. I ran the car today and placed a thermometer in the radiator neck to check the temp and watch for water movement. However i saw no water moving and the temp in the radiator neck never went over 160 even though i ran the motor for a good 20 minutes, the temp light never came on. I have not replaced the sending unit or replaced the water pump yet. could there be an obstruction in the heater core that would prevent water flow?
Thanks in advance for any ideas.

 

[Saar]

The heater core is not the only coolant pass.
There is one more "trail" for the coolant - at least in my 1988 one.
Anyway, if the coolant does not flow there may be few reasons:
1. Is there enough coolant?
2. t-stat is stuck.
3. water pump is too worn.
4. Radiator is stuck - no coolant passing.
5. too much air in the system - but I'm pretty sure that is not the issue here.

Since you measured the temp in the radiator and it was hot, I guess there is some flow that you didn't notice (other wise, it shouldn't be hot...).

You may check the sending unit and I would check the water pump too.
Saar.

 

[69alfa]

First thing to do would be test the sender and gauge .

Extend two wires from the sender one ground ,one gauge so you can get the sender into a pot of boiling water.Gauge should read 212 deg or close to it .

You could try to test the high temp sender also but it may be hard to get it up to the required temp .

You can ground the sender to test the light .


A non contact thermometer would be a great investment .
You will be able to "see" where the heat is getting to.

Infrared Thermometers

Also loads of fun if you have a cat . Ours will chase the laser for hours.

One note they do not work well on shiny surfaces . Put a piece of black tape on any shiny areas and you will get better readings.