Originally posted by apachebob:
1958 1/2 ton with new 160 thermostat, new sending unit in intake manifold. Needle starts out at the bottom with the truck cold. after a couple minutes starts to climb but goes all the way to the top before the thermostat opens. Is there a way to adjust the temp gauge? There is a little metal tab on the internal workings which looks like it might be adjustable. in or out? how much? any ideas before I wing it?
It could be several things. Start by pulling the thermostat, and putting in a pan of water on the stove, along with a thermometer. Heat the water, observe. It's surprising how many thermonstats don't behave as you'd expect. ;-)
Second, I alway drill a ~1/8" hole in the thermostat flange, in such a way as to allow water (and air) to 'leak' by. This solves trapped air problem.
Do those, see if the problem goes away. Remember rule 1: trust your gauges. If the gauge says the motor is hot, maybe it's really hot..... 8-)
Cheers!
George
