The dreaded "No Heat"

[ltd02]

I recently went theough hell with my coling system also. Put in 2 different thermostats. Ii did the boiling water test on the 2nd one 1st to make sure it was operating. My cooling system would absolutely not circulate on its own after a flush no matter how i tried to bleed it. I ended up removing the upper hose and filling the block up with coolant through a funnel as well as the radiator. Then did the bleeding process. Thats what worked for me.

At this point I'd probably give this a try.

 

[LibertyTC]

I have gone over all like some 5 times, both hot and cold. New info just discovered. May or may not be related. Recently, the check engine light has been coming on. My bro had a program and was able to get the code. Looked it up just now and its, Engine cold too long! Weird.

I totally missed this. The engine is taking too long to warm up code.
Many have had other Thermostat brands, out of box fail to the open position, or worse closed to over heat.
There is only 1 best recommended thermostat to be using= Mopar 6817 4083 AA
51450[/ATTACH]"]

You must be registered for see images attach

Here is install info:
51452[/ATTACH]"]

You must be registered for see images attach

 

[ltd02]

(yeahthat)

Like Belvedere said before.

That doesn't mean that it opens at the proper temp. If it opens too soon, there won't be much heat. If I was going to all that work, it sure would have gotten a new OEM 'stat.

That said, I agree with the guy who said it sounds like air in the system.

Or... could be a bit of both?

 

[belvedere]

Or... could be a bit of both?

It sure sounds that way. I'm sure that if he installs a new OEM 'stat, and bleeds the system well, the problem will be solved.

 

[LibertyMan02]

I'm thinking so. A bit more ground made. Found a ever so slight bleed on the thermo housing where the rad hose is. A very small seep from that hose. Another thing is, the sloshing noise under the dash has a relation to the heat output. Was testing some things and out of the blue got some ok, but not great, heat out the vents. Today, I was sitting in the jeep on lunch break. Was working throttle building engine heat when the sloshing stopped and the heat started to really blow. Still, it wasn't great. I'm thinking air. I don't have the Allen wrench to turn the bleed screw so, I 'm out of luck there. I'm pretty sure I saw Mopar on the thermo when I pulled it, but I'll replace it when I flush the system.

 

[WestlakeOH]

I am puzzled to my no heat issue too. my 03 KJ was blowing lukewarm air. I backflushed the heater core twice and was able to get a little heat for a short period and then it went back to barely warm. the vehicle was not overheating or had any leaks so I assumed the no-heat issue was water pump or thermostat related. So I went ahead and pulled the dash back and replaced the heater core and actuator (since I had the dashed pulled). beside a little corrosion at the very bottom, the old core looked good. After reinstalling everything, i ran the engine to temp and the heat is still luke warm to cool.

I am not sure where to look next...could this be a water pump or thermostat issue?

 

[tommudd]

I am puzzled to my no heat issue too. my 03 KJ was blowing lukewarm air. I backflushed the heater core twice and was able to get a little heat for a short period and then it went back to barely warm. the vehicle was not overheating or had any leaks so I assumed the no-heat issue was water pump or thermostat related. So I went ahead and pulled the dash back and replaced the heater core and actuator (since I had the dashed pulled). beside a little corrosion at the very bottom, the old core looked good. After reinstalling everything, i ran the engine to temp and the heat is still luke warm to cool.

I am not sure where to look next...could this be a water pump or thermostat issue?

One of the first things I would of done was the thermostat

 

[CzarKJ]

I am puzzled to my no heat issue too. my 03 KJ was blowing lukewarm air. I backflushed the heater core twice and was able to get a little heat for a short period and then it went back to barely warm. the vehicle was not overheating or had any leaks so I assumed the no-heat issue was water pump or thermostat related. So I went ahead and pulled the dash back and replaced the heater core and actuator (since I had the dashed pulled). beside a little corrosion at the very bottom, the old core looked good. After reinstalling everything, i ran the engine to temp and the heat is still luke warm to cool.

I am not sure where to look next...could this be a water pump or thermostat issue?

What temp is your upper hose vs your lower hose? T-stat is easy change.

 

[JasonJ]

Thermostat replacement for sure; and note that the bleeder hole must be positioned at the 12 o'clock (straight up) position.

Then air. Both of you guys with crap heat have air in the system for sure. If it isn't leaking, heater core and radiator not clogged, proper coolant, good t-stat, blend door not stuck, only thing left is pockets of air in the cooling system. It'll get trapped in the heater core quite often, as it is in one of the higher points of the cooling circuit.

Once air is in the heater core, there is not much actual heat for the blower fan to expel out the vents.

 

[profdlp]

WestlakeOH - sorry for the off-topic, but I am the same age as you and lived in Westlake for about a dozen years before taking a job down here in VA. I'm moving my fiance into an apartment in Westlake next week. I do have heat, though.

Anyway, once I'm back up there we will have to meet up. Maybe we can do some off-roading at Crocker Park.

 

[kage860]

Don't know if it was mentioned before but its also worth checking that the hoses going to the heater core aren't mixed up.