Join Date: Nov 2006
Location: San Antonio, Texas
Thermostat Acting Strange
My rebuilt 350 was running fine, normal temperature. The key accidentally was left on and the Pertronix and coil fried. I replaced them with the dual point setup and a Pertronix coil, 1.5 ohm.
When I finally got the dwell set and the car running again, the thing overheats while idling after about ten minutes. I took the 195 degree thermostat out and replaced it with a 180 degree new one. It still overheated so I tested the thermostat in some hot water and it opens properly, but when I put it back on the car, it does not open. There is pressure in the upper radiator hose, its it pretty hard. I believe the thermostat is not opening.
What could cause this?
BTW, it runs fine when you remove the thermostat. Does not get hot at all.
New 4 row radiator, new radiator cap, new hoses, new water pump.
Timing is set at 12 degrees and dwell is at about 33 degrees for the dual point distributor (Mallory).
68 Coupe, 350, M20 frame off restoration (a work in progress).