Water temp gauge testing

[steelman]

I have the dash out of my 1978 280Z and am trying to make sure that everything is working properly. The car is a 250 GTO replica with a small block Chevy engine. I have the proper sending unit (280Z) and the dash is a Ferrari look alike, so it is tough to get at the gauges.

Is there a procedure to verify that the gauge is working properly while it is out of the car?

Thanks,

Ralph

[jhm]

If you're able to hook the gauge to the sending unit, drop the sending unit in a pot of boiling water....the gauge should read 212 deg F. Obviously, this technique requires that the gauge and sending unit are properly powered and grounded (i.e., you'll probably have to rig temporary hot and grounding wires from the car to the gauge and sending unit in order to conduct this test).

 

You can do a variation of this test with a pot of water of various temperatures and a thermometer. This allows you to compare the thermometer's readings against those of your new gauge.

 

Be careful not to let the sending unit touch the pot itself....might result in a higher reading than the boiling water. Also, I'd be careful to keep the wires out of the boiling water...could lead to a short, and the insulation could somehow get damaged.

 

Hope this helps.

Edited February 11, 2010 by jhm
completeness

[sileightygx]

if the gauge is already out of the car, you can also just hook it up directly to the sending unit on the engine. while its running you can just verify if it works or not. boiling water in a pot with a sending unit is also smart because you can verify if the gauge is reading somewhat accurately.

[steelman]

Thanks Guys.

Ralph