My 5.0 HO engine will not warm up. It shows right at the first tick mark at the "c" on the temp gauge and the heater puts out no heat. I replaced the thermostat so it shouldn't be that. I am running a manual aftermarket fan without a fan clutch so it's going all the time, would that keep it that cold? I also have a new radiator cap on it, I think 15 or 16lbs. What could be causing this? Thanks, Jason.
Your fan could be part of the problem. Put a clutch back on it and see what happens then.
The fan shouldn't prevent the engine from warming up because the thermostat should keep the coolant in the engine and out of the rad until it warms up. My guess would be the new thermostat you installed is defective - I had that happen on my old Cherokee and the beater Dakota (which is still awaiting replacement)
Feel the top radaitor hose after the engine has run about five minutes, if it is getting warm the thermostat ain't holding the coolant in the block. Either its defective or the housing may be corroded and letting coolant bypass... Make sure you have a 195* stat as well, a 180* won't give a lot of heat in sub zero temps...
or the thermo is in backwards
classic I find this alot ussually with an overheating problem though...
Yeah the upper rad. hose does get warm right away so I guess the new one is deffective. The housing was in pretty good shape and the t-stat seating well. Why is this such a common problem? If it's a new part it should work right? where should I get a better one from? I can get this one replaced for free but I don't want to go through replacing it over and over.
The best thermostats are the OEM ones, avaliable only from Ford dealers. All aftermarket, especially the "fail safe" ones, are pr0ne to failing, in my experiance.
Exactly ;) The cheap aftermarket parts are, well, cheap. What do you expect for eight bucks?
OEM's are good. I've also had success with Mr. Gasket brand.
Yeah, but cheap to me usually means it won't last as long or won't perform as well. But not working right out of the box is a little much even for cheap. It should say on the box "may not work" or something so that you know. This time I will go for a brand name one or from ford. Thanks guys. Jason.
It does say that! Didn't you know thats what AutoZone means!
I actually got it from advance but basically the same thing I guess. I've been burned on cheap parts before, I think I have finally learned. I just figured something simple like a thermostat wouldn't be too bad, but I was wrong.
Yes, atleast go to napa. They sell Stant thermastats. Stant has been around forever. I think car quest has better parts as well.
I just picked up a Stant one from Advance for my Z-7 yesterday. I installed a new one a couple weeks ago and have had the same problem...it would not heat up, and it has that stupid fixed fan on it too.
I got heat today, but after X-mas that fan is going away for an electric one. It just needs to be thin as the I-6 takes up a bit of room in front.
FWIW, the Stant stat was listed as "Premium".