thermostat question

Have any of you guys put a 180 degree thermostat in your 5.9? I did this weekend and it seems im getting no heat

I run the 180 in all my dodge trucks with the exception of v10 simply because I have not needed to yet.

One question did your heat work prior to the install of this thermostat? If so I would bet the thermostat is stuck open for one reason or another. If not, then you cant blame the thermostat could very well be the heatercore.

I have a 180 t-stat and have no problem getting heat.

190/195 is the factory heat range. Coolant temp dropping by 10-15 degrees won't change heater operation much except in the dead winter where it will go from feeling very warm to moderately/luke warm. I'm talking 20 degrees and below.

If you had no heat prior to changing the thermostat then its not the thermostat, if you had heat before the thermostat, it may be the thermostat but its unlikely, crib deaths on anything other than bargain bin thermostats is pretty low.

Some things to try. Warm the truck up to operating temp by driving it or idling for 20 minutes. Feel the upper radiator hose, it should be pretty hot, just about 180 degrees. If not, rev the truck to a couple grand and see if it warms up. If it doesnt then feel the heater hose, it should be hot. If neither are hot then you're likely looking at a bad waterpump, to tell for sure feel the bypass hose which is behind the A/C compressor and between the intake and block, it should be hot.

If the rad hose is hot then you'll need to check the heater hoses. They should be firm not spongy, and both should be hot. One will be slightly hotter than the other. If one is hot and the other is cold, or both are cold/lukewarm then its highly probable that your heater core is plugged. Sometimes a borderline heater core can fail just by draining and refilling it. Don't bother trying to flush it, most of the time doing so, even gravity flushing, causes leaks and will just lead to replacement anyway, and coolant residue on your windows. That sucks to get off.

thanks guys and yes i did have heat before i changed the thermostat, and the water pump is brand new also .. i will check the heater core for leaks

Ok don't be insulted by this question, but did you make sure you installed the t-stat right side up? It wouldn't be the first time someone put it in upside down.
Just trying to help you.

its in there right i spent quite some time on it.. i actually replaced without taking the a/c compressor and alternator loose so it was kind of a booger fighting the housing out

also is there a good way to check the heater core for leaks? i know most times if its major it will cover the passenger floor board with antifreeze... and im not having that issue

BoDuke said:

also is there a good way to check the heater core for leaks? i know most times if its major it will cover the passenger floor board with antifreeze... and im not having that issue

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Turn the heat all the way up and switch to the face vents and turn the fan on the lowest or second lowest setting and ram your nose onto the vent. Does the air smell sweet? If yes, its leaking.

Other than that, no real way to tell if its leaking without pulling it. Have you felt the hoses for temperature yet? Thats really the first step as a leaking heater core will still heat the air a lot, it will just give your feel a bath too. A clogged heater core won't make much heat at all.