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-   -   No heat...? (http://www.wranglerforum.com/f282/no-heat-76269.html)

Mikekaz1 01-17-2011 03:12 PM

No heat...?
 
Hey I have a 2000 4.0. And my heat is next to gone. I did a flush and fill on the antifreeze. But that didn't help. Does anybody have any idea how to fix?

neverfastenough1 01-17-2011 03:22 PM

Since you are messing with the antifreeze, I am guessing your engine temp isn't rising? Antifreeze has nothing to do with the cabin heater. Unless you just thought the core was clogged and were trying to flush it out?

jasonwrangler 01-17-2011 03:28 PM

first, 1997+ uses a electric blend door. and some times the switch or the motor might go bad resulting the blend door stuck at cold position when the knob is turned to hot.
to test that, open your hood and feel both in and out pipes on the heater core make sure the heater core is heating up.
if you feel one pipe is hot and the other is just warm, that tells you the heater core is clogged up and needs flushing using a water hose running low pressure water through it to flush out the gunks. back flushing usually gets the stuff out better but try both.

Mikekaz1 01-17-2011 03:29 PM

Quote:

Originally Posted by neverfastenough1
Since you are messing with the antifreeze, I am guessing your engine temp isn't rising? Antifreeze has nothing to do with the cabin heater. Unless you just thought the core was clogged and were trying to flush it out?

Yeah my temp gauge is perfect. And I did the flush kit for that reason exactly but still have problems with cabin heat. I'm just wondering if anyone knows some secret I don't know or if I just have to suck it up and get a whole new heater core

sevenservices 01-17-2011 03:32 PM

Double check all your relays and fuses as well... just to eliminate them as a possible cause.

perkalator 01-17-2011 03:38 PM

My 2000 tj had the exact same issue. The blend door was not going into the correct position. This was due to the back of the heater controls the connector for the dampner controls had melted and shorted.

98tj25l 01-17-2011 03:40 PM

Quote:

Originally Posted by jasonwrangler (Post 995586)
first, 1997+ uses a electric blend door. and some times the switch or the motor might go bad resulting the blend door stuck at cold position when the knob is turned to hot.
to test that, open your hood and feel both in and out pipes on the heater core make sure the heater core is heating up.
if you feel one pipe is hot and the other is just warm, that tells you the heater core is clogged up and needs flushing using a water hose running low pressure water through it to flush out the gunks. back flushing usually gets the stuff out better but try both.

Couldn't have said it better myself! However, I have a 98 that's still the cable driven blend door. I'm just not sure when they stopped using those.

Also to test the blend door you can usually hear it moving as you turn your temp dial.

jasonwrangler 01-17-2011 03:57 PM

Quote:

Originally Posted by 98tj25l (Post 995626)
Couldn't have said it better myself! However, I have a 98 that's still the cable driven blend door. I'm just not sure when they stopped using those.

Also to test the blend door you can usually hear it moving as you turn your temp dial.

I thought they changed it in 98. great information there.

neverfastenough1 01-17-2011 04:14 PM

Blend door is common problem in Jeeps.

neverfastenough1 01-17-2011 04:28 PM

You can see the blend door actuator under the passenger sider of the dash. Turn the key to the on position and rotate the temp knob. You should be able to see the shaft on the top of the control turning. If it doesn't turn, drop the control out and open it up. Look for corrosion and water. See if the shaft is frozen. Try to clean it with some contact cleaner and put some grease back on the gears. try to turn it again to break it free. If you get it to turn, hook it back to the wire and see if it works. Its like 150 or so for a new control.

Wesboy 01-18-2011 02:47 AM

Just to clarify, did you flush the heater box? I had crystal clear coolant in the radiator but heaps of brown junk came out of the heater box. Could not believe what came out. The difference in heating was amazing.

Mikekaz1 01-18-2011 08:21 AM

Quote:

Originally Posted by Wes Hughes
Just to clarify, did you flush the heater box? I had crystal clear coolant in the radiator but heaps of brown junk came out of the heater box. Could not believe what came out. The difference in heating was amazing.

Uhh I think I did? I spliced in the hose fitting for the flush and fill right into what I believe is the return from the heater core.

Mikekaz1 01-18-2011 08:22 AM

Quote:

Originally Posted by neverfastenough1
You can see the blend door actuator under the passenger sider of the dash. Turn the key to the on position and rotate the temp knob. You should be able to see the shaft on the top of the control turning. If it doesn't turn, drop the control out and open it up. Look for corrosion and water. See if the shaft is frozen. Try to clean it with some contact cleaner and put some grease back on the gears. try to turn it again to break it free. If you get it to turn, hook it back to the wire and see if it works. Its like 150 or so for a new control.

Ok. Cool, thanks alot I will def look into that one.

Mikekaz1 01-21-2011 09:39 AM

Uh so you can hear the actuator working. And the fan works. But I did notice only one of the hoses going into the core was hot, I did a flush kit before when I first got it. Does anyone know a more direct way of flushing the core out and not just te radiator?

Peepers 01-21-2011 10:03 AM

Quote:

Originally Posted by jasonwrangler (Post 995586)
first, 1997+ uses a electric blend door. and some times the switch or the motor might go bad resulting the blend door stuck at cold position when the knob is turned to hot.

If you have a dail and two sliders you have a mechanical blend door. 3 dials and it is electrical.

brandonchino 01-21-2011 01:17 PM

I had the same problem, which I fixed by flushing the heater core and coolant system. To backflush the heater core I shot a garden hose through it the opposite direction. I believe it was in the lower hose and out the upper. Ultimately, I had to do that a bunch of times over several days and even used an air compressor to totally free it up. Just be careful not to give it too much pressure. Towards the end, I actually wound up flushing both directions. After I started getting better heat, I flushed the coolant system entirely. Hope this helps.

Mikekaz1 01-21-2011 03:50 PM

Quote:

Originally Posted by brandonchino
I had the same problem, which I fixed by flushing the heater core and coolant system. To backflush the heater core I shot a garden hose through it the opposite direction. I believe it was in the lower hose and out the upper. Ultimately, I had to do that a bunch of times over several days and even used an air compressor to totally free it up. Just be careful not to give it too much pressure. Towards the end, I actually wound up flushing both directions. After I started getting better heat, I flushed the coolant system entirely. Hope this helps.

Cool thanks man I'll do that

Steves98TJ 02-13-2011 01:27 PM

Had a similar problem. Followed the advice of a poster and flushed out the heater core only. There are two lines to the heater. One goes into the thermostat housing, the other into water pump(2.5L). I had a garden hose repair female end from Home depot I bought for like $1. It fit perfectly into the hose that goes into the thermostat housing. Attach garden hose the fitting. Remove the other hose that goes to water pump. Turn garden hose and full blast and watch that brown crap puke out of the core. I let it run for a good 10 minutes until it was perfectly clear. At first only a little sludge came out but eventually the water flowed unrestricted.
I reconnected lines and filled radiator with clean fluid. Voila heat!
I went ahead and flushed the whole coolant system while I was at it. Easy to do. If you dont have the plastic female end, I suppose you could hold the garden hose to the heater hose with your hand. It will still have plenty of pressure to clean the core.


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