I drive a 1978 F100 with a 302 and recently changed the thermostat to a 180; the old one would fluctuate between 1/3 and 2/3 of the bar. I plan to check the actual temperature with a thermocouple, but that'll be later. I currently run 10W40. The new thermostat runs at or below 1/3 of the bar.

The owner's manual states 10W30 oil should be used, but the previous owner had the engine rebuilt and recommended the higher viscosity, though I'm not sure how much he knew about it. I put 10W40 in before I saw the oil specification in the manual.

Because the engine runs cooler, should I move back down to 10W30 or will 10W40 work fine? No problems with oil pressure, but I'm concerned that not enough oil will get through at the lower temperature.

Thanks a bunch.

 

My older brother bought that thermostat online a while back. I just popped it in without thinking.

 

180 is too low for a 302, even though after a while it will reach temps, just takes a while. Does the temps go up when driving? Even though I do not really trust the in dash gauges, most temps I have seen usually run 1/2 to just a little above the mark. My Vic has a heating problem that I cannot figure out, but shortly, hopefully it will be over.

As for the oil, if I lived in a hot climate I would run the 10/40, but in a cold climate it would be 10/30. Much easier starting when the temps drop below 0.

 

Planning to replace it with a 195 degree Stant Superstat. Even at this point the temp sticks just below 1/2 of the gauge, not 1/3 like I said.

 

I would drill a 1/8 hole in it or remove the little ball if equipped and drill it out there. Doing that lets air out of the system a lot faster and will even give a little flow when filling it.

 

Some of the thermostats have a little valve pin that serves that purpose, but that's a great idea. It won't affect the bypass any because it's such a small hole.

How do you feel about aftermarket temperature gauges? Are they usually accurate, or am I better off using a type K thermocouple connected to a digital display?

Edit:

I taped a neodymium magnet onto my top coolant hose close to the radiator connection point; this should catch any metal shavings that happen to come off the pump.

 

A digital is better. I wish I had one, but with the problem I am having, one is on the list. I am dropping a lot of bucks into the front end and want to be sure. I just cannot figure this out though. I did not have this problem until the damn fan blade broke, I just wonder if that sensor that runs the speed is defective. I need to look in my junk and see if I kept the old shroud.

 

You read my mind. I have been looking at both Autometer and ISSPRO. ISSPRO does not list any digital gauges though.

 

I guess a 195 thermostat would be the norm?

 

The problem with a 192/1295 thermo is the engine compartment gets real hot in the summer and the crud that passes for gas vaporizes. 180 is a little cold but most engines will go passed that anyway in the summer unless you have some kick butt fans and radiator. I have electric fans with an adjustable thermostat and I run the 180 in summer and switch to the 192 in the summer.
The old Roberts/Shaw style therm is the best.

 

I'm just asking because I've got a 5.8 I installed in my 56 project.