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heater not working

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Old Nov 24, 2013 | 08:32 AM
  #1  
McGuinness's Avatar
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From: Waynesville, NC
Year: 1999
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Engine: 4.0 L I6 H.O. (242 CID)
Default heater not working

Hello I recently bought a 88 comanche where the owner before to previous owner put a 98 Cherokee motor in it and it doesn't have hot air the line to the compressor aren't there but I'm getting a/c and Idk what I'm missing exactly help would be greatly appreciated
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Old Nov 24, 2013 | 11:24 AM
  #2  
Just Another XJ from AK's Avatar
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Year: 1988
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Engine: 4.0L In Line 6
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I'm going to take a stab at this while you sober up.
I am going to make the assumption that it still has the open loop cooling system. And not knowing what is (or isn't) there, I will start at the coolant bottle.
There should be a "T" on each of the lines just before the coolant bottle. If there isn't, you will need them. From each "T", you will need to run a hose to the two tubes from the heater core.
Before you do, you should check your heater core to make sure it isn't clogged or even worse, leaking.
A picture would greatly help.
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Old Nov 24, 2013 | 11:27 AM
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Year: 1997 (RHD)
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Originally Posted by McGuinness
Hello I recently bought a 88 comanche where the owner before to previous owner put a 98 Cherokee motor in it and it doesn't have hot air the line to the compressor aren't there but I'm getting a/c and Idk what I'm missing exactly help would be greatly appreciated
What?
You have no lines to the compressor but you're getting A/C, as in your A/C is working??

Is the blower motor working? Do your heater hoses both get hot when engine warm?
No hot air could be heater core needing a (back)flush.
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Old Nov 24, 2013 | 11:46 AM
  #4  
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Originally Posted by Roler

What?
You have no lines to the compressor but you're getting A/C, as in your A/C is working??

Is the blower motor working? Do your heater hoses both get hot when engine warm?
No hot air could be heater core needing a (back)flush.
Yes there are no lines going to the compressor but I'm getting a/c on vent, max, defroster every setting with the fan turned to max but no heat I've let it sit for 30 minutes a.d still no heat and Idk WTF the guy who put it in did but where the heater core sticks out of the firewall he put silicon all over it and a white rubberish tube coming out with a rubber elbow on the end connected to nothing.. so.. I'm confused...
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Old Nov 24, 2013 | 11:48 AM
  #5  
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I get off work at 2:30 ill post pictures
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Old Nov 24, 2013 | 11:55 AM
  #6  
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am curious about that construction....but it sounds like your heater core isn't even connected to something. Do you even have heater hoses running alongside the valve cover?
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Old Nov 25, 2013 | 09:58 AM
  #7  
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From: Waynesville, NC
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Sorry about yesyerdays turns out I had a lot to Do after work but here's the pics

heater not working-forumrunner_20131125_105542.jpg



heater not working-forumrunner_20131125_105622.jpg



heater not working-forumrunner_20131125_105645.jpg
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Old Nov 25, 2013 | 11:00 AM
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Pic 3 looks like the vacuum lines. They control your vents. Start from the vacuum bottle behind the passenger side front bumper. The line should go to a tee before it enters the firewall. The line then continues to a vacuum fitting at the rear top of the intake manifold. It looks like your heater hoses are all hooked up.
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Old Nov 26, 2013 | 10:24 AM
  #9  
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Seeing that your heater hoses directly connected, I'd back flush the heater core and check the air blend door for operation. You may want to check your thermostat to make sure it isn't stuck open like mine was.
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Old Nov 26, 2013 | 08:28 PM
  #10  
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Originally Posted by Just Another XJ from AK
Seeing that your heater hoses directly connected, I'd back flush the heater core and check the air blend door for operation. You may want to check your thermostat to make sure it isn't stuck open like mine was.
I was wonderibg how you woild tell if its open I just got my jeep a month ago and going through winter with out heat is killing me
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Old Nov 27, 2013 | 05:00 PM
  #11  
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I used an infra red thermometer on the engine after driving it on the highway for a while. The block was only 100° and the hoses at the heater were only 60°. Granted it was only -20° at the time.
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Old Nov 28, 2013 | 06:46 AM
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Originally Posted by Just Another XJ from AK
I used an infra red thermometer on the engine after driving it on the highway for a while. The block was only 100° and the hoses at the heater were only 60°. Granted it was only -20° at the time.
Crappy thermostat.
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