1994 F350 that won't warm up

If its a gasoline engine, thats sounds about right..

I would use a minimum 185*F thermostat... If you can, get a 195*F therm...

Ford Tech

Thanks for the reply.

I've done even more research and I found that the temp gauge sitting around 1/3 could be normal. What does make me think there is no thermostat is the fact that it takes a long time for there to be heat and the heat isn't that hot. Could this be normal? How hard is it to change the thermostat?

And yes it is a gas engine.

well your first clue should have been that you bought it from the NAVY, DUH........ anything after that is just on YOU, DUH........ever thought of buying a book on the truck, DUH.......

And what exactly is wrong with Navy vehicles? You got on the wrong boat here mister. I am a Navy VET... They dont do anything to their engines that you wouldnt do to yours. They have factory trained techs working on these trucks, just like the dealers..

Ford Tech

With that vintage, the guage will go somewhere around the "O" with a 197 deg stat. If you replace the stat, it will go a bit higher on the first few warmup cycles, but will settle in where it was in most case I've seen. If it has the HD cooling which is spec'd on almost every gov't vehicle, it has a higher capacity cooling system requiring a bit longer to get fully warmed up. Unlike the older cooling systems, these have a bypass directly to the radiator instead of internal recirculation like many older systems. This tends to slow warmup along with a couple of benefits like de-aereating the coolant and warming the throttle body to prevent icing. If a slow heater is the problem, it may need a good flushing to clean a partially blocked heater core. They can be a bit sentitive to scum and scaling.

Lugnut