kd460

Well the wrenching gods bestowed me with a heater core project this weekend, and while I'm in there I am going to replace the evaporator. I have been reading the posts regarding the dash disassembly and thanks to all of those who have posted the info. Hopefully things will go smooth.

My question is with the ac lines that connect to the evaporator. I have not found any information on how to disconnect those. I did pick up a 5 piece set of those plastic spring loaded "a/c and fuel line connection tool" thingys but of course it does not show you how to use them.

Looking for a description on how to disconnect the lines. Heck I'll even take any advice on the heater core and evap project if you want to throw it my way. Thanks, YD

bandit408

Make sure you have recovered all the freon from the ac system before you disconect the lines. Otherwise, you will freeze your fingers after the line pops off. Just slide the plastic disconnet around the line and push it into the fitting. All it is doing is moving the spring in the fitting so you can pull them apart.

kd460

Bandit, thanks, yes, I have since found out that it is easier than it looks. Thanks for the tip on the freon, I am stopping on my way home from work to get the system emptied. Then it's fun time.

Does anyone know if I need to replace the dryer since I am opening the system? I know I need to replace about one ounce of oil for the evaporator alone, but curious about the dryer. KD

Busboy

If the AC was working ok then do the job quickly and have it evacuated and recharged soon and there's no need to replace the dryer. When reinstalling the heater plenum watch for the little black vacuum line that runs through the fire wall at the same time.

Flashman

You will need 8 AC O-rings that need to be replaced, and oiled with the proper lubricant before re-assembly

I just did this on my 1999, pulled the entire dash out.

kd460

Yes to no problems with the ac, I'm hoping to get the system opened and closed all on saturday. Possibly evac the system later that day as well, but may not be able to get it evac'd till monday. Hopefully that won't be to long of a wait, but not much else I can do. Whats the worse that can happen, I need to then replace the dryer later? If so I can live with that.

8 O-rings? How many do I need for the evaporator? That is all I planned on doing was disconnecting the evaporator. I just picked up a 24 pc assortment of AC o-rings in various sizes and quantity. Is 8 for the whole system or just for the evaporator?

Also the guy at the parts counter told me I need PAG 100 and that is what I have. It is the non pressurized can. I was told to pour 1 ounce in the evaporator just before installing. Is this the right stuff?

Thanks for the info guys, I am just starting things in the garage. Hopefully the next time you hear from me, I won't be cussin and swearing (which means bad things are a happenen). KD

kd460

Well everything is apart, it looks like a bomb blew up in the truck. I'm done for the night.

Both the heater core and the evaporator were shot, nasty, full of crud and debris. It looks like the previous owner used some stop leak in the cooling system from the appearance of build up on the outside of the heater core.

I also noticed yellow greenish dye in the A/C system, so who knows what was done with that. Can only wait and se I guess.

Now comes the hard part, getting it all back together. I guess I'll just follow the Haynes manual and "assembly is reverse of disassembly" KD

1-2-3

Please keep us informed on exactly what parts, supplies, tools, and do's and don't do's. I need to do this exact thing, except my ac is dead and my heater is good. Like you, I'll do both when I break down and dig in.

kas83

First off, you WILL NOT freeze your fingers if the system is not evacuated. When pulling my head off, there was a slight miscommunication between me and my buddy on who had ahold of it, and it got dropped on the lower line. My hand was pinned between the head and the fenderwell, and the head hitting the tube ruptured it. I didn't get froze, just got full of the yellow/green oil that is in the system. Made a huge puff, and it was done. I was covered with that dye and glowing, and it tastes horrible. Got cleaned up, washed my mouth out with Scope, and all was good. No ill side effects since then, only thing is the clothes I was wearing went in the trash.

I'm tacking the same project myself, getting ready to pull the dash out and get to the housing. I have both the heater core and evap core, just waiting on a sunny day to work on it. Not incredibly hard, just time consuming.

kd460

Should a new thread get started for this??? Hopefully this info won't get ignored by others who need to do this project because of the title

I'll be glad to post any info when all done, but I just basically followed the steps in my Haynes manual, did do some searching on this forum as well.

https://www.dieseltruckresource.com/...ght=evaporator

https://www.dieseltruckresource.com/...d.php?t=183867

Curious what others have used for replacement foam tape. There is lots of it around the evaporator, and some around the heater core.

I will probably just go to home depot and match it up as close as possible. I assume I should stick with the closed cell foam, as open cell foam would probably just stay wet all the time. Also wonder about the foam insulation around the pipes of the evporator. I'm gonna see if I can get the old pipe insulation off.

Having second thoughts about not replacing the dryer. Think I might call around and look for one of them as well. The hoses are disconnected and thend are taped up with electrical tape, but the humidity is supposed to go up tommorrow. My neighbor has a pump for me to use, and I have a manifold gauge set. Just never took the time to read up on how it is used. Guess what I'm doing in the morning? KD

1-2-3

One thing that I can add...when I replaced my dash, I learned it's on a pivot system. Disconnect the batteries, wait 20 minutes to disarm the airbags, remove the glove box, remove the two kick panels, remove the panel under the steering column, dixconnect the small cable for the shift indicater, remove the 4 bolts holding the column up, remove the 5 screws across the top of the dash near the defroster.

Now the dash will rotate down and you can reach the top bolts for the ac/heater housing. Once unbolted, rotate the dash back up and drop the housing out the bottom.

The dash roatated very far if I remember right. I wanted to replace my evap and heater core but funding wasn't right at the time. Something silly like the kids wanted to eat supper or have shoes or somethng.

kd460

OK, so things are all done. It actually went together easier than I thought. Spent alot of time on the ducting, as all the foam seals just about turned to dust, so I replaced all of those, cleaned everything up, new closed cell foam vibration isolation around the heater core and evap. I copied what was there originally.

Lubed up the blower motor, lubed up all the pivot points on the diverter doors, and the cable. That took about 3 hours of dinking around including a trip to home depot for the foam insulation/seals. The diverter doors work really smooth now and all of the duct work is nice and clean.

Everything works as it should so far, no coolant leaks and I have a vacuum pulled on the ac system right now (29 in Hg) and am watching it to see if it drops. It's been about a half hour and all is good so far. If my informatyion is correct, I need 32 oz of freon in the system. I'll do that tonight or in the am.

The only problems I have is now the steering wheel lock does not work and I started a new thread on that. I also have one left over screw

I'm not gonna worry to much about the steering wheel thing unless someone tells me it is a major problem. YD

kas83

You guys that live outside WI are lucky, you can do all the A/C stuff in your driveway. I have to take mine to a shop to get everything evacuated and then recharged. Stupid WI laws.

I just got mine put back together, gotta pull it out one more time to hook up the blend door hoses. Can't wait to get this whole ordeal done, get the head back on, and run it.

kd460

Well, head over to MI and we'll get you hooked up! What did you leave disconnected? One hose or the multi connector? If it's the multi connector, then you don't have to pull anything.

What are the WI laws that stop you from working on it anyways?

I did not need to remove any hoses to the diaphrams, I just kept them conneted while doing all the work of cleaning, foam gaskets, etc. KD

kas83

I left the multi connector unhooked. Will have to look at it tomorrow. I should be able to snake everything around and get it hooked up. Wisconsin laws require you to be A/C certified AND own/operate or be employed by a business that is also A/C certified. Can't mailorder the kits even, can only go through parts places or dealerships if certified.