heat gauge or temp sending units

F

ford1953

Junior Member
having trouble with my v8 flathead, temp gauge shows in the middle when you turn in key and stays there. after about 20 min it starts to climb all the way to hot. any ideas on what problem could be.?
 
Sonds like it is not grounded properly. Is there thredd sealer or Teflon tape on the threads? The unit must have a good clean ground in the head to work properly.
 
TJ said:
Sonds like it is not grounded properly. Is there thredd sealer or Teflon tape on the threads? The unit must have a good clean ground in the head to work properly.
Click to expand...

I think he is talking about the gauge, not the sending unit?

Or am I "cornfused"?
 
it just started doing this last week, i checked sending unit both are teflon coated on threads, don't know how to ck guage out
 
ford1953 said:
having trouble with my v8 flathead, temp gauge shows in the middle when you turn in key and stays there. after about 20 min it starts to climb all the way to hot. any ideas on what problem could be.?
Click to expand...
the gauge should go to "Cold" if the key switch is turned on and the engine is cold. disconnect the wire from the main harness at the two pole sender and ground it. Briefly turn on the ignition switch. If the gauge moves to the cold position the gauge is good. Do not leave the ignition switch on. If the gauge looks to be OK remove the other lead from the two pole sensor and connect the two wires together. This will bypass the two pole sensor. Turn the ignition switch on and observe that the gauge moves to cold. If you still see the the gauge start at mid scale then drift to Hot the single pole sensor is bad or not grounded. If teflon tape or pipe sealer was used on the sensor that may cause a bad ground. The body of the sender provides the ground path. Metal to metal is required.
 
You must log in or register to reply here.
Back
Top