69 Roadrunner ...Temp Gauge Not Working

[needacheaperhob]

Hi all....hopefully someone has an idea of what the issue may be?

My 69 Roadrunner (383 4 spd) temp gauge isn't working, it doesn't move at all.
When Ibturn on the heat, I get BARELY luke warm air out of the vents. It's almost difficult to tell if there's any warmth at all in the air coming out.

All the other gauges work and the coolant is fine. I'm up north and was just giving it a 15 mins warm up while in storage and this is when I noticed the gauge issue.

Could this be a faulty thermostat?

Any ideas on why the gauge doesn't move at all and isn't blowing waem air?


Thank you.

 

[pnora]

Unplug the sending unit. Ground the wire with a jumper to a clean ground. Turn the key on the gauge should go all the way to hot. If it does the gauge and wiring are OK. Even on a fully warmed up engine the gauge should move to the very cold side. If it does not I suspect a sender is bad. However with the low heat I would install a quality thermostat and see then what the gauge does. Cold ambient temps and 15 minutes may not be enough time to warm up. What was it doing before going in storage?

 

[68BabyBlue]

Unplug the sending unit. Ground the wire with a jumper to a clean ground. Turn the key on the gauge should go all the way to hot. If it does the gauge and wiring are OK. Even on a fully warmed up engine the gauge should move to the very cold side. If it does not I suspect a sender is bad. However with the low heat I would install a quality thermostat and see then what the gauge does. Cold ambient temps and 15 minutes may not be enough time to warm up. What was it doing before going in storage?

I went through this with one of my cars. No gauge reading with what appeared to be a new sending unit. I did the ground test, and the gauge and wiring were functional. Put in a new sending unit, which resulted in the gauge moving about a sixteenth of an inch when the car was fully warmed up. Sure can't assume proper function with reproduction parts. Baby Blue had the original factory stuff in place, and it still worked perfectly after five decades. I did need to clean the connections once in a while. I had the heating problem with my '62 Imperial years ago, after I had the engine rebuilt. The shop hooked the heater hoses up backwards.

 

[Longknife]

When you ground that wire and turn on the key shut it off as soon as it reached hot or you will burn up the gauge.

 

[Demonic]

Could this be a faulty thermostat?

Could be stuck open. Find A buddy with a test thermometer or even an IR temp gun, top of rad will tell you something after 30 min run time.

 

[Bird 426]

Car that I bought warmed up alright, Heater motor didn't seem to work. Box was kinda full of mouse insulation.