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Topic Review (Newest First)
12-25-2014 08:02 AM
VARIABLE9
Quote:
Originally Posted by USMC_SgtMaj View Post
Wow, I followed all the steps on this thread and solved my problem. First thing I did was run the defroster on "hot" then moved it to "cold" and yes, I had plenty of air on cold. So I figured I have an obstruction(s).

I removed the Battery, removed the ECM, removed the fan motor and there it was, years of leaves, cottonwood debris, etc. It was amazing how much debris was in there. I vacuumed and blew it all out.

It works great now...THIS FORUM ROCKS!!! Below pictures represents only half of what was up against the heater coils.

[IMG][/IMG]

[IMG][/IMG]
Similar issue on my 2000 but at same time I replaced the non-functioning resistor so all the heater settings would work. Heat is better, not 100% - I suspect more investigation is necessary!
12-22-2014 04:16 PM
dj1michaels
2012 Wrangler does not blow hot air...

My Wrangler heats to luke warm and that's all. Found that the heater cores and radiators get plugged with sand out of the engine block. Totally plugs system so it won't get warm. Luckily, I found problem a few hundred miles before my warranty expired. Dealer at first tried to shine me on. I filed a complaint with Chrysler, NOW dealer is changing heater core out, and gave me a free rental. If I let my warranty expire, all I would have gotten was a bill....
12-09-2014 05:10 PM
Shark_13 Awesome, I want to do this one of these days....
12-09-2014 04:43 PM
USMC_SgtMaj Wow, I followed all the steps on this thread and solved my problem. First thing I did was run the defroster on "hot" then moved it to "cold" and yes, I had plenty of air on cold. So I figured I have an obstruction(s).

I removed the Battery, removed the ECM, removed the fan motor and there it was, years of leaves, cottonwood debris, etc. It was amazing how much debris was in there. I vacuumed and blew it all out.

It works great now...THIS FORUM ROCKS!!! Below pictures represents only half of what was up against the heater coils.

[IMG][/IMG]

[IMG][/IMG]
11-17-2012 08:24 PM
s14sh3r
Quote:
Originally Posted by erickpl View Post
You got pics of how you did all this? I have a 97 as well and while I'm getting hot air, I wouldn't mind taking a look at the blower motor and checking things out.
I didn't get any other pics, sorry. I wish I would have.

Quote:
Originally Posted by LiftedTj View Post
Im having trouble removing the hoses so i can flush the heater core. Is there are trick to it?
You need to be very careful so you don't damage the core. I used a pair of pliers and GENTLY twisted the hose where it goes over the pipe back and forth until it was free. Don't just crank on it.
11-17-2012 08:18 PM
LiftedTj Im having trouble removing the hoses so i can flush the heater core. Is there are trick to it?
11-16-2012 11:02 AM
erickpl
Quote:
Originally Posted by s14sh3r View Post
Mine's an early 97. It was easy to get out. I had to remove the battery and PCM and remove 3 bolts from the blower.

humpaco, I'd just have to look and see how the later model TJ's are set up. As it was, I could see part of the core. A small inspection mirror and a flashlight let me see all of it.
You got pics of how you did all this? I have a 97 as well and while I'm getting hot air, I wouldn't mind taking a look at the blower motor and checking things out.
11-16-2012 10:00 AM
jeepsrgreat Thanks for everyone's help and ideas. I did get the flush done, but not the inspection. I air seemed like it has worked it's way out of the system.
The heat is so hot now, it's uncomfortable to have my foot on the gas with the fan on full.
New concern now is that the cable to the blend door seems to be no longer connected to the slide control. At least I can reach the door leaver from the driver's seat.
11-16-2012 09:46 AM
s14sh3r
Quote:
Originally Posted by wmdavis007 View Post
Mine is a 97 (it's the same as yours), once the blower is out don't look straight in...look from the side, toward your drivers side and you will see it. A flashlight will help too.
I just thought of something, too. Raise your hood all the way back against the windshield. If you're using the prop rod, you might not be able to get in there to look.
11-16-2012 06:26 AM
wmdavis007
Quote:
Originally Posted by jeepsrgreat View Post
I didn't see my core when I pulled the blower. Wish I could. Mine I a 98....how do I see my core, or do I have to pull it from inside.
Mine is a 97 (it's the same as yours), once the blower is out don't look straight in...look from the side, toward your drivers side and you will see it. A flashlight will help too.
11-15-2012 07:58 PM
scott howard 1-I would buy a preston flush kit and flush out your system. 2- move the temp control from cold to hot with your hand on the air box and see if you can feel the blend door opening and shutting good.
11-13-2012 04:45 PM
Diverdown87 I didn't see where anyone had posted this in here but be careful using CLR. The bottle has a warning on it that it should not be used on aluminum....I pulled this of their web page:CLR Frequently Asked Questions

What will CLR do to copper or aluminum?
CLR will take the finish off of aluminum and copper.

Can I use CLR to clean out my radiator?
No, CLR should not be used on a car radiator for two reasons. First, CLR may not be compatible with the internal metals of the radiator. Second, it could have adverse effects if the CLR is not rinsed out completely.

I did see where someone else had used it on their heater core but said they only let it sit in there for a few minutes IIRC 10 minutes at most and "had no issues yet".

*I just flushed my heater core out after having driven around for a year with it bypassed. Hooked a hose to the upper HC line and flushed it out then hooked it to bottom line and did it again. Repeted process once more each way and then put new heater lines on. Ran up to optemp, topped off rad and "tested" at idle both heater and defrost. Defrost blew way hotter than before I bypassed. Heater I haven't ben able to really test..Was 65* this morning.*
11-12-2012 08:53 PM
homerj FWIW. i flushed the core with water and compressed air and i got the warm air hot.
11-12-2012 04:37 PM
jeepsrgreat
Quote:
Originally Posted by s14sh3r

If your blower removes from behind the battery like mine did, look inside the hole and to the right and you'll see the core. I had to use a small mirror and a flashlight to be able to see all of it. To get in there, I put a piece of small fuel line over the nozzle of my blower and it worked great.
Thanks

I'll have to do it again on a warmer day. It's minus 25 C here. I already have it all put back together. I did get a flush done though. Now it seems like there is some air trapped in the inlet hose.....sigh
11-12-2012 03:35 PM
s14sh3r
Quote:
Originally Posted by jeepsrgreat View Post
I didn't see my core when I pulled the blower. Wish I could. Mine I a 98....how do I see my core, or do I have to pull it from inside.
If your blower removes from behind the battery like mine did, look inside the hole and to the right and you'll see the core. I had to use a small mirror and a flashlight to be able to see all of it. To get in there, I put a piece of small fuel line over the nozzle of my blower and it worked great.

11-12-2012 01:55 PM
Stout6
Quote:
Originally Posted by wmdavis007 View Post

No removal needed to flush your heater core, just locate your two heater hoses...the one going into the top of the motor (into the thermostat housing) is the inlet. Then disconnect both hoses from the front of the motor, not at the firewall. You want the water to go into the outlet heater hose so it will come out of the inlet, it will back-flush the core. Hope that's not too confusing. I would turn the water off and on a few times the dislodge any debris. When your done just hook them back up...after your motors run up to 200-210* let it cool down and top off the radiator with more antifreeze. Simple as that.
But...it could also be your blend door in your heater box, Jeep's have a weak blend door that can wear out over time. You can look up the fix on Google by typing Heater Treater Jeep. It's a metal door not the flimsy plastic one that ours comes with. Hope this helps.
That helps a lot. Never messed with it before. I'll give it a shot this after noon. Also, I've noticed most everyone says they're jeep floats in the 200-210 range. Mine has never broken 195. Could that have anything to do with it?
11-12-2012 12:15 PM
jeepsrgreat Going to try the flush now, but the garden hose is frozen. Minus 25 C is not the preferred temp to fix the heater. The hose is having a hot bath in the tub now.
11-12-2012 12:11 PM
jeepsrgreat
Quote:
Originally Posted by s14sh3r
Well, here's what I found when I pulled the blower motor:

Here's after I blew it out best I could:

I haven't put it back together yet and there are some other things I need to do before I can run the heater to see if it's improved, but I'm betting there's an improvement because a good 25% of the core wasn't allowing airflow through it. I'll post results later.
I didn't see my core when I pulled the blower. Wish I could. Mine I a 98....how do I see my core, or do I have to pull it from inside.
11-12-2012 07:25 AM
wmdavis007
Quote:
Originally Posted by Stout6
I am having the exact same issue. Just warm air. I'm willing to bet the heater core is clogged. I have an '03. Can ya'll give me some tips on removal. I'm mechanically inclined but have never worked on the heating system of any car. Any pointers would be greatly appreciated. Thanks.
No removal needed to flush your heater core, just locate your two heater hoses...the one going into the top of the motor (into the thermostat housing) is the inlet. Then disconnect both hoses from the front of the motor, not at the firewall. You want the water to go into the outlet heater hose so it will come out of the inlet, it will back-flush the core. Hope that's not too confusing. I would turn the water off and on a few times the dislodge any debris. When your done just hook them back up...after your motors run up to 200-210* let it cool down and top off the radiator with more antifreeze. Simple as that.
But...it could also be your blend door in your heater box, Jeep's have a weak blend door that can wear out over time. You can look up the fix on Google by typing Heater Treater Jeep. It's a metal door not the flimsy plastic one that ours comes with. Hope this helps.
11-11-2012 08:56 AM
Stout6 I am having the exact same issue. Just warm air. I'm willing to bet the heater core is clogged. I have an '03. Can ya'll give me some tips on removal. I'm mechanically inclined but have never worked on the heating system of any car. Any pointers would be greatly appreciated. Thanks.
11-11-2012 08:07 AM
humpaco Heat at last, heat at last.

My issue was not that the core was blocked but rather that the blend door was leaking and not seating properly. To refresh my symptoms: I was getting hot air out of the vent with the fan off and on low but the higher I turned the blower motor, the cooler the air would get.

I bought the aftermarket door from Heater Treater. I didn't have the time to do it so I took it a local radiator shop recommended by the HT website. I am glad I did because it didn't fit perfectly and he had to modify a part a bit to make it fit. He showed me pictures and I would have struggled to do that. He also flushed the core with a combination of water and air. I think the air make a difference because the 3 times I flushed it with just water, I got nothing but clean, clear water out. He said before the flush he was getting 110 degrees out of the vents. After flush with air and water; 135 degrees.

Flush made a difference but my real issue was a not-properly seated blend door.
11-10-2012 07:40 PM
wmdavis007
Quote:
Originally Posted by powellst View Post
I did the simple heater core flush with a garden hose today, and am AMAZED at the difference in heat. It was barely warm at high, and now it will literally roast you. !
Last night I used a Prestone Flush n' Fill kit and some Super Flush on the whole system. Flushed with plain water, then drained, poured in the Super Flush and topped with water then flushed that out after running for 10-15 mins then re-flushed with water. Then I back flushed the heater core with plain water and a garden hose....then with a portable air tank (would refill with water once it blew out, did that 3 times). Wow the junk that came out was nasty...very rusty. Then I replaced the upper and lower radiator hoses (I replaced the thermostat earlier this week). I also added some NAPA Radiator Anti-Rust to help with my rust problem.
I have HEAT now!!! I had to cut the heat off halfway to work tonight, usually it doesn't even get warm until I'm halfway.
11-06-2012 03:32 PM
powellst
Quote:
Originally Posted by wmdavis007 View Post
I just did this tonight, mine is a 97 as well and it is VERY easy to get to. The hardest part is taking the battery out. I'm not sure if this will help my heat because my heater core wasn't very dirty...but I still blew it out with an air hose. Think my heat is poor because the heater core is blocked up with scale and rust. I just replaced my thermostat yesterday and my antifreeze was rusty brown. I'm going to get some radiator flush and flush my whole system then just the heater core. Hoping to get some good heat this winter, I dealt with lukewarm heat the whole cold season last year.
But this is very easy to try for those of you with poor heat.
I did the simple heater core flush with a garden hose today, and am AMAZED at the difference in heat. It was barely warm at high, and now it will literally roast you. !
11-06-2012 03:10 AM
wmdavis007
Quote:
Originally Posted by s14sh3r View Post
Mine's an early 97. It was easy to get out. I had to remove the battery and PCM and remove 3 bolts from the blower.
I just did this tonight, mine is a 97 as well and it is VERY easy to get to. The hardest part is taking the battery out. I'm not sure if this will help my heat because my heater core wasn't very dirty...but I still blew it out with an air hose. Think my heat is poor because the heater core is blocked up with scale and rust. I just replaced my thermostat yesterday and my antifreeze was rusty brown. I'm going to get some radiator flush and flush my whole system then just the heater core. Hoping to get some good heat this winter, I dealt with lukewarm heat the whole cold season last year.
But this is very easy to try for those of you with poor heat.
11-04-2012 10:10 PM
humpaco s14sh3r, I'll bet with all of that dust and gunk you got off your core that solves your problem. Great pics.

Still trying to figure out why my air gets cooler the higher I turn up the fan. With the fan off I get good hot air out of the vents.

I'll try the CLR this week. I think i covered all the other bases.
11-04-2012 07:59 PM
s14sh3r
Quote:
Originally Posted by 572 View Post
s14sh3r...What year is your Jeep?

I was just wondering if you had to remove your blower motor from under the hood (behind the battery) or from inside the Jeep? I think they changed where you access the blower motor sometime around 01 or 02.

I think I may need to clean my heater core like you did and it looks like you had decent access to the heater core.
Mine's an early 97. It was easy to get out. I had to remove the battery and PCM and remove 3 bolts from the blower.

humpaco, I'd just have to look and see how the later model TJ's are set up. As it was, I could see part of the core. A small inspection mirror and a flashlight let me see all of it.
11-04-2012 07:46 PM
humpaco
Quote:
Originally Posted by scott howard
A easy check to see if your heater core is stopped up with dirt on the outside and not letting the air flow thru it freely to transfer the heat to the ducts of the Jeep is to set it on defrost and temp on cold and feel how much air is flowing . Now switch it to Hot and see if it loses a lot of air flow( it will be a little less just because it has to blow thru the core but it should not be a lot less ) if so your core is clogged with dust and dirt and need cleaned .
The best way is to remove it but if you pull the blower motor and you have a air compressor and a nice long air gun you can sometimes blow it out.
Be careful and not bend the honeycomb closed.
Scott, I get the same airflow through the top vent on hot and cold so it doesn't sound like a clogged/blocked core. (right?)

Also, I removed the blower motor to see if i could gain any kind of access to the core to blow it out with compressed air. I have a 2002 so it is removed from under the dash rather than under the hood behind the battery. Couldn't see or feel the core so couldn't really do too much.

I'm out of ideas at this point. Any other suggestions?
11-04-2012 07:36 PM
humpaco Jerry, I I flushed through the firewall only. Good suggestion about the hoses. Will do that this week.
11-04-2012 06:26 PM
scott howard This preston flush kit works very well and cost only around 15 dollars.
And the preston radiator flush and cleaner chemical will remove an unbelievable
extra amount of rust and corrosion that a water back flush can not remove and it only cost 6 dollars.
I install these flush kits on all my Jeeps and do a back flush every 3 years.
The whole labor time to install kit and do a flush is 20 minutes.
If you do this and pull the blower motor and clean the outside of your heater core with compressed air you will have heat like when it was new.
11-04-2012 05:28 PM
572 s14sh3r...What year is your Jeep?

I was just wondering if you had to remove your blower motor from under the hood (behind the battery) or from inside the Jeep? I think they changed where you access the blower motor sometime around 01 or 02.

I think I may need to clean my heater core like you did and it looks like you had decent access to the heater core.
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