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I NEED HEAT, I"M FREEZING!!

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Jeepinparrothead

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Discussion starter · #1 ·
Ok, here is the deal. I have replaced; water pump, radiator, thermostat, hoses,and the entire climate control unit behind dash. Guess what, I don't have heat. I can't figure it out for the life of me. I put the heat on high, and while I am driving the heat will be, oh say, kinda warm. It never gets hot, EVER! This is with it all the way on hi heat. Now just to cover the newbie stuff, the thermostat that I replaced it with was OE and it goes with the long side, if you know what a thermostat looks like, down in the motor. I am pretty sure that is right. I have replaced it three times in this Jeep. Anyway, if that is right I have no idea what in the world can be wrong. FYI, I check the upper rad hose after a short drive from installing the newest thermostat, and it had no pressure in it. That is not normally to my knowledge. Please help the girlfriend is having a fit. Oh yeah and to top it all off, my rear defrost stopped working, now I have to figure that out.

5.2 motor. HD rad, Mopar water pump and everything. Any help would be appreciated.
 
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#2 ·
Have you tried backwashing the coolant through the heater core yet?
 
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#4 ·
What do you need heat for in AL?

Is the engine getting up to temperature? A quick look at the FSM shows you have the thermostat installed the proper direction, did you get it from the dealer or somewhere else?
 
Discussion starter · #5 ·
Box store, I knew I would get the why do you need it in Alabama thing. Well, to you 32 might not be too cold but down here, we close down town. That is frigid. I am glad that I put it in right!! :pant: I have put so many thermostats it is not funny. It is the OE temp though.
 
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#6 ·
disconnect the heater core outlet hose and stick a water hose in the end of it and turn the water on. itll leak coolant all over so... make sure you are over a storm drain that leads to the ocean... j/k...
 
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#7 ·
And if that works good try taking the thermostat out and checking it..

Put a pot of water on the stove and get it to a slight boil.. Drop the thermostat in , It should open then pull it out.. (Not with your hands..) and set it in the sink or something.. It should close pretty quick..

That means its not the thermostat... It could be bad.. Or maybe your engine is just not getting up to temp.. If you have an electric fan .Turn it off and see if temp climbs..

If all else fails .. You can try the old hillbilly stand by....

Cardboard in front of the radiator...
When I lived in Michigan my 4 banger Nissan was so cold it would blow icicles out of the vents .. Then I put the cardboard in and all of a sudden the heat worked... :thumbsup: Sounds dumb but the air and the outside temp where so cold that it kept the truck from getting up to temp..
the cardboard stopped air from blowing across the radiator and it would run up to normal temp...


Note: IF you do this and you over heat .... I take no responibility.. :lol:
It is surely not cold enough in AL for this.. I am just throwing it out there..

Does sound like either your heater core is clogged or your thermostat is not opening..

Good luck.. :thumbsup:
 
Discussion starter · #8 ·
Thanks swamp the cardboard thing is interesting to say the least. I have never heard of that. Now back to the backwashing, just disconnect the outlet and put a hose in? Where in the world is the water going to go? Do you mean disconnect all of the Heater core hoses and run water through it?
 
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#9 ·
Figure out which way water and coolant is supposed to flow through the heater core and then force water through it the other way. Any crap that got stuck in it will get flushed out the inlet.

Make sure the t-stat is working, check all hoses are heated up as well. Make sure the engine comes up to temp. Check for obstructions in the t-stat housing. Make sure that your heater hoses have not collapsed internally.

Is it possible that you are actually having problems with the climate control knobs and you are not fully switching over to heat?

Cardboard in front of the radiator is used to block off part of the radiator and force the rest of the radiator to make more heat. If the engine is coming up to the t-stat temp value then don't use the cardboard.
 
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Discussion starter · #10 ·
here is the update. I just got it up to operating temp and check for cold and hot hoses. The inlet to the heater core is hot, the outlet is cold, alas a stopped up heater core. I am going to try and backflush it and see if that helps. I wonder how much a new heater core cost since this might not work. I appreciate it guys. I will trying the backflush tomorrow and I will update again.
 
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#12 ·
Swamp Boy said:
Bulldog.. I knew a yankee would know about the cardboard..
Click to expand...
Yep it works well too.

Jeepinparrothead,

The heater core is cheap, getting to it sucks. The dash has to come apart. If you decide to replace it yourself you will have to disco the A/C system. Make sure to wrap exposed lines to prevent contamination infiltration. My HVAC friends recommend to wrap with paper towel and then wrap with black electrical tape. This will seal out contamination and significantly decrease moisture infiltration.

Once you have it all back together, pay to have the A/C system evacuated under a vacuum to remove moisture and contaminants. Moisture will mix with the oil and produce acid that will eventually eat your A/C components.

You should be able to get by by flushing the system for now. Just prepare for a mess.
 
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Discussion starter · #13 ·
Yeah I am not sure that the heater core is the problem. Now the climate control doors that I replace about 10 months ago don't work anymore. So, my mechanic doesn't do the doors, I don't take apart the dash. I hate to say it but my time is worth more than that. So, it is going to the dealer and they can figure it out. I don't have time to mess with it right now (it's tax season). Some guy rear ended me while I was in Birmingham so his insurence is going to give me a car and my body shop guy said that he will tell them that it is going to take awhile to fix the Jeep so that I can have the rental while it is at the dealer and at the body shop. Can't beat that with a stick. :thumbsup: But if you have anymore ideas please let me know, I hate sending it to the dealer but right now I can't waste my time throwing things at it and it not work. So if you have anymore ideas please let me know. I won't be checking the board very much for the next little bit so if you could just call if you know exaclty what the problem is and it is simple to fix. I would appreciate it. 256-759-9683
 
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#14 ·
have you tried pulling error codes from the ATC system? If there is a problem with the doors it should be be able to pinpoint it for you.

The procedure is something like hold both the recirc/AC buttons down whilst turning the temp knob one click, should display 00, release buttons, then press either the recirc/ac buttons to get the codes.
 
Discussion starter · #15 ·
when I first crank the Jeep it will display a Er on the display I didn't know you could check them I will try it.
 
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Discussion starter · #20 ·
Update: I have had it to my mechanic and they don't have a clue. I know I said I was taking it to Jeep but I was trying to same some money. Ok. This is the second one of my normal mechanics that have said they don't know. Now what is happeing is that the upper rad hose will collapse frequently. But I do not overheat or anything. I get ok heat but not great. I am at a complete loss. For replacing everything, I thought I would have a good cooling system. I do have a small crack in my timing case cover that leaks rad fluid but it is not too bad. What will cause my upper hose to collapse like that??? Do you still think it is the heater core. I don't know. I have been advised by several people that blowing out the core with water or air is not a good thing. So I hate to take it to chrysler and them rape me......oh well
 
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Jeepinparrothead
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