1950s 1954 Temperature Sending Unit

[Scott Halver]

Hello,
I have a '54 Cadillac with the temperature gauge going to 3/4 hot when driving in moderate weather, thermostat housing reads approx 171 degrees via a laser temp gun.  I purchased a "new" NOS sensor for '53-'55 to install.  I removed the old sensor and found it had a lot of sealant on the threads.  The old sensor is smaller in size and as such the new sensor is not going to thread into the smaller hole.  The engine serial number matches the '54 car but maybe I have an earlier intake manifold ?  Do I just clean-up the threads and put the old sensor back in with NO SEALER ?  The gauge does go from cold to 3/4 hot so the sensor is doing something and the guage is working.  The old sensor is not brass, possibly aluminum or steel, new sensor brass.  The wire from the firewall was cut and a different connection attached.  Thanks SHalver

[The Tassie Devil(le)]

G'day Scott,

You can get adaptors to fit the smaller senders in the large holes.

Plus, there should not be any sealant around the threads of any electric sender unit that uses the thread as a ground.

Yours could be minimally touching, but any touching should be a good ground.

Bruce.