HVAC box refurb questions/advice

[A-man930]

I took this box apart two or three years ago and I'm now ready to begin clean up, repair, and reassembly.  Before I begin, has anyone on here gone through this process?  If so, is there any advice you could share?  I'm not even sure exactly what I'm asking for, but I have a bad habit of tearing deep into things just to later find out somebody has already figured out a better way to do something.  

 

I have a plan working to remake the large foam seals.  

 

[Limeyjeeper]

If you look at my build I do describe what material to use.

[eaglescout526]

I tore mine down to get it really cleaned out. Wish I had some insulation material to make heating and cooling a bit better. But too late now. 

[A-man930]

How did you clean it out?  Wire brush?  Soap and water?  Solvents?  The OE adhesive-backed stuff seems like it'll be a pain to remove.  

 

I notice the metal parts inside have a fair amount of surface rust going on... really tempting to get that all painted, but that would require drilling out rivets and generally talking it all further apart... How far did you take it?  

[eaglescout526]

Oh I more or less used a scrub brush and some soap on plastics that weren’t covered. The material for the doors and what not I left alone due to aging and disintegration of the material. Like I said. I cleaned it so it wouldn’t have any funny smells and not be dusty but didn’t get to do a restoration like I wanted to.
 

I took mine almost all the way down, if I could remove it without drilling something out to remove a part, it came off. Seems rust on the metal bits is going to be normal though.  

[ghetdjc320]

I power washed all the components on mine. A worthwhile upgrade (albeit, requiring some modification) is to fit the 97+ XJ plate and fin evaporator to delete the tube and fin factory unit. Goo gone will remove the old adhesive fairly well. Take your time to make sure all the clamshell housing is realigned properly and we’ll sealed or you’ll have air leaks. My AC was like a new car after all that work. Well worth the effort. I’ll be tackling this again soon on my new build. 

[MiNi Beast]

I took mine out and just left it out, best 15lbs weight savings ever. Who needs heat or a/c.? 

[A-man930]

4 hours ago, ghetdjc320 said:

A worthwhile upgrade (albeit, requiring some modification) is to fit the 97+ XJ plate and fin evaporator to delete the tube and fin factory unit. 

 

Well I already have a replacement evaporator in there that is different than the factory one... 

 

[Eagle]

2 hours ago, MiNi Beast said:

I took mine out and just left it out, best 15lbs weight savings ever. Who needs heat or a/c.? 

 

Especially in Minnesota in January ...

[75sv1]

I couldn't find Limey's Build Thread. The newer AC uses a filter in the tube to regulate the PAG oil. Not sure what A-man's evap is from or modified. here's alink for a possible upgrade. ??

Jeep Cherokee '97-'06 - HeaterTreater

[A-man930]

4 hours ago, 75sv1 said:

I couldn't find Limey's Build Thread. The newer AC uses a filter in the tube to regulate the PAG oil. Not sure what A-man's evap is from or modified. here's alink for a possible upgrade. ??

Jeep Cherokee '97-'06 - HeaterTreater

 

Can't speak for any other years, but my temp blend door is cable-actuated.  

 

My evaporator is a replacement I got from NAPA over 10 years ago.  At that time most all of their A/C parts were sourced from 4 seasons 

 

I did struggle to get acceptable performance from the A/C back in the day but I never was able to determine exactly why.  My biggest suspicion was a problem within the box because PLENTY of condensate would come out the drain but the discharge air was only so-so.  

[A-man930]

Here's Limey's posts about his box refurb:

 

 

[A-man930]

 

20 hours ago, ghetdjc320 said:

A worthwhile upgrade (albeit, requiring some modification) is to fit the 97+ XJ plate and fin evaporator to delete the tube and fin factory unit. 

4 hours ago, 75sv1 said:

The newer AC uses a filter in the tube to regulate the PAG oil.

 

Interestingly, the late-model XJ is an orifice tube system vs. the early one using an expansion valve; this is the "filter" 75sv1 mentioned and it changes the system fairly significantly.  

 

The late model is not only a plate/fin design, it also uses spring lock connections instead of tube nuts - this will make it impossible to attach my expansion valve... so is part of this "some modification" game converting to an orifice tube system entirely?? 

 

 

VS the early design:

 

 

[A-man930]

Wait a minute, NAPA shows the 91-96 XJ (also MJ 90-92) evaporator having the tube-nut fittings for an expansion valve and being plate/fin!  Also, 93+ will be optimized for R134a... perhaps that's my problem with the whole system in general.  

 

 

Also found this discussion helpful: https://www.naxja.org/forum/showthread.php?t=1122182

 

This vendor might be useful as well: https://jeepair.com/

[scguy]

I used 94 XJ (or 93+) AC components in my MJ for a "made for R134a" system. 

[eaglescout526]

I think I have an early HO evap in my MJ. Works great. If you’re moving from R12 to R134, I found a bulletin from Chrysler on the amount you need in an old R12 set up to R134. Pretty helpful. I think I’m using a hodgepodge of Renix and HO parts. Even the condenser I got was a NOS one and said R134 ready. 

[A-man930]

This is also interesting:

 

https://www.amazon.com/Spectra-Premium-7-4173-Condenser-Cherokee/dp/B000C7QC4O

[A-man930]

Well I couldn't help myself. This stuff just looks so crusty in there and there were only a few rivets to remove. Though I did crack part of the housing 

 

[A-man930]

I love having a blast cabinet! 

 

[A-man930]

This piece was somewhat more difficult to remove. Lots of patience required, it'll be good knowing all the metal parts inside aren't going to rust away for a while longer.  

 

 

[A-man930]

I should have known this was how it would end up 

 

[Tex06]

On 1/29/2022 at 2:13 PM, A-man930 said:

I should have known this was how it would end up 

 

That's the biggest problem with having a blast cabinet.

I also tore mine down and rebuilt a few years back.....but never found hoses that fit so I still don't have A/C. *sigh*

 

I had a crack in my plastic housing, a little fiberglass and black paint and she was right as rain again!

[A-man930]

19 hours ago, Tex06 said:

I also tore mine down and rebuilt a few years back.....but never found hoses that fit so I still don't have A/C. *sigh*

 

 

What hoses were you missing?  The ductwork or vacuum hoses?  

[A-man930]

Made a bunch of headway today!  Evaporator came in; It sits just a little too tall in the box so I used a heat gun to soften the bottom corner opposite of the drain of the box for a little more clearance, the lines are arranged differently (side-by-side) so the foam gasket has to be remade.  

 

 

 

 

And after all that, I have to AGAIN remake the gasket 

 

 

 

 

 

[Salvagedcircuit]

Awesome work!
Does anyone know if the fittings for this '96 ac evap unit are the same as on the '89 comanche? Didn't the evap core fitting sizes change through the years?
According to rock auto, the 96 evap unit you used is the Four Seasons 54812 / TYC 97347 /UAC EV4178PFXC / GPD 4711548.
Thanks.