Temp Sending Unit Sealer ?

[440sixpack]

My temp gauge worked before I rebuilt my engine, ever since it hasn't. I grounded the wire out and the gauge climbs right up.

I reused the sending unit so the only thing that's changed is I wrapped it in Teflon tape before I reinstalled it.   could this be my problem ?   I'm going to put a new sending unit it in but if the Teflon is the problem I don't want to drain it and do it again.   if so what should I use in it's place ?

[Joe-JDC]

Try to wrap the Teflon tape on just the first three or four threads, and tighten until the unwrapped threads make contact with the manifold.  You can narrow the Teflon tape by stretching it over the threads and it will not cover the whole width.  Use a deep socket to tighten the sender, not a wrench.  Joe-JDC

[C6AE]

Try grounding the wire to the housing of the sending unit.

edit; I should add that this is just a quick way to "test" whether or not the sender itself is grounded!

[C8OZ]

Have always used the Motorcraft liquid/gel teflon thread sealer in a tube and don't recall ever having a contact issue.

[Rory428]

I use a bit of the white Teflon paste on the threads. Being a pipe thread, technically no sealer should be required anyhow. I use it so the threads won`t stick or gall up if I ever need to remove it at a later date.

[BigBlueIron]

Brass into cast iron no sealer is required and usually don't need any with aluminum either. If you do the previous advice giving is spot on. 

[67428GT500]

I use tape every time and I've never had one not function. I wouldn't do it without sealer, especially with dissimilar metals. Squeeze the connector a little bit to make sure the connection is conductive. If it's not, go to NAPA and spend the 7.00 and replace it.

                                                                                                                  -Keith