PROBLEM Need Some help.
I have a Stewart Warner mechanical gauge temp gauge. This truck has a new radiator, new water pump, new fan clutch, new timing chain,& new hoses. I have never had a heating problem in the past. I had a thermostat stick on me this last May. The temp never got above 240 degrees and only for a very short time a few seconds. So when I got to Kingman AZ. I bought aa AutoZone fail-safe 180 degree thermostat. Installed it and it worked fine for 3 months. when I came back north. and the weather cooled off I realized the thermostat was stuck open and I wasn't getting water temp over 150 degrees. So I went to CarQuest bought a 180 degree thermo. installed it and it would run to 180 at idle when I would drive it it would go from 180 to 200 for awhile then jump to 240 and cool right back to 200 degrees. I drove it 40 miles with no better results. So this AM I installed a used 180 CarQuest themo I had and it would run a steady 200 degrees drove it 50 miles and no problem. I bought 2 more new thermostats on Carquest one Napa both top of their lines. installed the Napa and it started doing what the first one did. I did pull it before it cooled and it was wide open. I installed the new CarQuest and again after a 50 mile drive the temp was all over the place.
Does anyone have any ideas. ALL I CAN FIGURE ARE BAD THERMOSTATS, I had them before but THIS MANY. I have heated water on the stove and only the Napa would open at 190 degrees. The rest at 200 degrees. would be closed by 180 degrees.
I'm fresh out of thought PLEASE SOMEONE throw something out. PLEASE.
This AM I put in another thermostat from NAPA. Loosened the gauge bulb and bleed any air out. Took it out and it ran 190-205 steady no fast fluctuations no going over 205. Ran 195-200 real steady @ 55-65 MPH. Ran it about 10 miles and seems fine. Again thanks for your responses. This was about to drive me NUTS and I'm already alittle off center anyway. Being and old mechanic it really just left me scratching my head.



