Help with heater core replacement on 2004 TJ

[MattFogel]

Hello,

I have recently started my heatercore replacement in my 2004 TJ. I am following instructions posted at: https://wranglertjforum.com/threads/how-to-replace-the-heater-core-on-a-jeep-wrangler-tj.471/ .

I am on step #19. "In the middle, just above the cylinder head. Note that this one holds the cowl plenum drain tube. The nut holding the drain tube must be removed, the cowl plenum drain removed, and then there is another nut underneath. "

I removed the 7/16 nut on top of the cowl plenum drain. but the instructions say there is another nut under the the cowl. I cannot figure out how to get the drain cowl off to get to the bolt. There is not enough room between the engine and the firewall of the jeep for me to pull it off.

Is there some kind of trick?

I can upload a video or pictures of what I am talking about.

Thanks in advance!
Matt

 

[Chris]

I've never done a heater core myself, but maybe @05pf13 or @yelloTJ will chime in.

 

[MountaineerTom]

Once the 1st nut is removed that holds the plenum in place, you should be able to wiggle it warping enough to unsnap it from the bottom of the cowl.

 

[MountaineerTom]

This is all there is to it. The tabs on top snap into the bottom of the plenum and have a foam seal between to two.

 

[MountaineerTom]

I just thought about this. Do you have a Motor Mount Lift? If so, I’m wondering if the tilt of the motor is making to space back there tighter.

I’ve never seen a Jeep with a MML with my own eye, so that may not be a problem. Maybe some others that have a MML can comment on that.

 

[MaloStapalo]

I just thought about this. Do you have a Motor Mount Lift? If so, I’m wondering if the tilt of the motor is making to space back there tighter.

I’ve never seen a Jeep with a MML with my own eye, so that may not be a problem. Maybe some others that have a MML can comment on that.

No MML on his jeep but good idea.

 

[MattFogel]

Correct me if I'm wrong. But I don't know if there is enough room to slide the cowl off the bolt that is coming out of the firewall. I have less than an inch.

I don't believe the jeep has a motor mount lift. Unless the first owner did it for some reason. I have honestly never thought to look.

Thanks for the help.

I will give it another try. I just don't want to break the cowl.

 

[MountaineerTom]

I didn't have a lot of room in there when I did mine, but I don't remember it being to tight that I couldn't get it off.

I used a bungee cord as a 3rd hand to help hold the wiring harness back when I has removing and installing the nuts. Maybe that will help give you a little room.

 

[MattFogel]

I didn't have a lot of room in there when I did mine, but I don't remember it being to tight that I couldn't get it off.

I used a bungee cord as a 3rd hand to help hold the wiring harness back when I has removing and installing the nuts. Maybe that will help give you a little room.

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Thank you!!! i got it.

 

[MattFogel]

So I got the hvac unit out... but i ran into another problem. I am not sure what this mechanism is called. but looks like a plunger directing heating/cooling. its hooked to both sides of the housing. i cant unhook the lever from the metal arm.

any advice?

 

[MattFogel]

I didn't have a lot of room in there when I did mine, but I don't remember it being to tight that I couldn't get it off.

I used a bungee cord as a 3rd hand to help hold the wiring harness back when I has removing and installing the nuts. Maybe that will help give you a little room.

View attachment 87967

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Thank you!

 

[MattFogel]

Okay thanks guys. I got everything apart. Theres a lot of hidden components. thanks for the help!. my friend, ryan has been telling me to "go to the experts". if nothing else it helps to take a break and talk to someone.

I think I got it from here.

 

[JMT]

Okay thanks guys. I got everything apart. Theres a lot of hidden components. thanks for the help!. my friend, ryan has been telling me to "go to the experts". if nothing else it helps to take a break and talk to someone.

I think I got it from here.

Nice work man. And good technique, step away, take a breather. Impressive.

 

[MattFogel]

One last question... Should I replace my blower fan for 150.00? the fan seems strong. but i would hate to have to pull this out again. whats the life expectancy on these fans?

 

[JMT]

Don’t know about the fan, but most replace the AC evap when they are in there. I haven’t got up the nerve to go in and replace mine yet. You got guys man. How would you rate the difficulty on a scale of 1-10?

 

[dbbd1]

On my 06, the blower motor just drops out of the bottom of the assembly. Move a little clip out of the way and give it like a 1/8 twist. If yours is the same, I'd wait until it goes out.

That's while it's still in the jeep.

 

[MattFogel]

On my 06, the blower motor just drops out of the bottom of the assembly. Move a little clip out of the way and give it like a 1/8 twist. If yours is the same, I'd wait until it goes out.

That's while it's still in the jeep.

Youre right to can pull this out from the passenger front.

 

[MaloStapalo]

Don’t know about the fan, but most replace the AC evap when they are in there. I haven’t got up the nerve to go in and replace mine yet. You got guys man. How would you rate the difficulty on a scale of 1-10?

Is your core leaking also?

 

[MattFogel]

Don’t know about the fan, but most replace the AC evap when they are in there. I haven’t got up the nerve to go in and replace mine yet. You got guys man. How would you rate the difficulty on a scale of 1-10?

So even tho my ac evap looks solid i should replace it?

 

[MattFogel]

Is your core leaking also?

yeahhh that's what made me start this repair. heater core was leaking and evaporating into the cab...