Temp gauge not working Chevy C15

[Frank v R]

send me a photo of the gauge , I may have a NOS one,

[Phil Waterman]

Hi Terry

Recheck the ground from instrument to body and engine to body. I've had problems where the gauge worked on the test stand and didn't in the truck, what it tracked out to was new paint on chassis and body made for a poor ground continuity, strangely the engine would crank. I've added an extra braided ground strap from engine to frame bolt that the battery connects to.

As a check how about a clip lead from the base of the sender to the instrument panel back.

Cheers Phil

[cletrac (RIP)]

All my Chevs use the bourdin tube gauge with the bulb on the end of the tube.

[TCLARK]

Originally Posted by cletrac

All my Chevs use the bourdin tube gauge with the bulb on the end of the tube.

Maybe my dash is a civilian??

[Grant Bowker]

I have definitely seen Bourdon tube temperature gauges in civilian Chevrolets. I had always though it was a function of model year. Pre-war and wartime mechanical gauges and changing to electrical about the time they went to 12V, about 1955 (but not sure the two changes are linked).

[TCLARK]

I am having trouble finding a sending unit for a early forties
gm truck.
Maybe my electric gauge is later manufacture altough it
does fit in the 1939-1946 gauge unit.
Terry

[Bruce Parker (RIP)]

Originally Posted by TCLARK

I am having trouble finding a sending unit for a early forties
gm truck.
Maybe my electric gauge is later manufacture altough it
does fit in the 1939-1946 gauge unit.
Terry

I'm also having trouble finding a GM/Chev electric temp sending unit, though in my case it's for a 12V system. I have tried a number of units for the block that look right and are NOS but don't work. My best guess is that they are designed for a dash warning lamp that is either 'off' or 'on' based on a predetermined temperature. What I need as a variable sending unit to read on the gauge. Any ideas?

[TCLARK]

Thanks Phil
I checked and cleaned that all good, the problem points
to the gauge, or mixed up wires to the gauge. I took pics of
the back of the dash before I took it apart and it was wired as I have
done, but it was not original wiring.

Frank, I dont know if the gauge will separate from the housing
probably should.

Cheers
Terry

[Frank v R]

yes the whole thing comes apart, I'll check and see what i have

[TCLARK]

I took the whole gauge right out and found an open between
a wire post and the inside frame, I scratched it up and used flux and a skinny
soldering gun and was able to lay some solder on the connection.
I reassembled and tested and now it deflects to full hot when I
ground the sender wire. Now to see what will happen when I get
the engine operating temp!

Thanks Phil and Frank I will see tommorrow if I can warm the engine
right up and get a reading. All 4 original gauges will be working then!
Cheers
Terry

PS Phil do you know how the wiper vacuum hose is plumbed thru the dash??

[Frank v R]

I checked stock and I do not have any temp gauges but I do have fuel and oil and speedos all NOS

[TCLARK]

Awesome Frank, that is so good to know, after I get the wipers up and running
I am tackling the speedo.
Do you happen to have a speedo cable or know where to get one.
I really need the outer part and I can probably put a new cable
inside!
Cheers
Terry