roggom

Hi all,

I was having issues with my lower pressure tubes freezing, wet passenger carpet and lots of water draining from my 99 XJ after running the AC for a bit of time.

Also the previous owner had a dog, and every time I ran the ac it smelled like wet dog and funky feet. Yeah nasty.

Now I know there may be other issues involved, and I am not claiming to be a certified mech( but 24 years in the Navy, I did my share of maintenance.), also I have read many posts that address this issue, so I came up with a few things to try, and it actually worked for me.

First there was a service note out that addressed this issue TSB 24-13-99 (google it for some links), it notes a new Low pressure cycle switch, PN 05015872AA. I picked it up for $30 at the stealership. Instructions are in the service note, In reality, super easy, no tools needed as it is hand tightened.

Next, I seen that there are these cans of foam that some folks use to clean their evaps, but I am not up to the $25 cost +shipping, and drilling a hole and running the risk of punching into my evap.

Thanks to Ol" Blue for pointing me to some great reference material, I saw that the input of airflow through the evap was accessable from the blower motor access hole.

So this is what I did,

Materials,
I can of scrubbing bubbles bathroom cleaner, Lemon,: this stuff foams up great and is only $3, it can be sprayed in any position

8mm socket or short nut driver (to remove the blower)

a 12" tie wrap/wire tie, I use this to clean out the evap drain, it is soft plastic, so not to puncture anything

an old toothbrush.


I started by removing the evap drain spout and running a wire tie with the tie end in and out of the drain to loosen up any clogs.


By roggom at 2011-06-25


Then I removed the blower fan, three 8mm screw and pulled it past the wire harness, it is a little of a PITA but be patient it will come out without breaking.


By roggom at 2011-06-25

Here you can see a bit of the crud that collected in the bottom of the ac box, there are a few drain holes along the bottom of the evap/ box seal, and some of them were covered with hair/dust/dead skin cell/ whatever/


By roggom at 2011-06-25

Now for cleaning, I decided to go with the least amount of force, in that I did not want to damage the coils in any way. I opted for some blue shop towels and just did a clean wipe of what i could reach.


By roggom at 2011-06-25

Next, I got the spray out and then sprayed all that I could reach into( in the ac box along the face of the evap, not the other ducting), the foam is great because it reaches into all the cracks and crevices.


By roggom at 2011-06-25

I let the foam die down and then got the toothbrush and started wiping in a circular motion, kind of brushing the junk over to the left and then down and pulled it out. Once the debris is wet it collects in to small hairballs. It may not look like alot, but a sandwich bag may not look threatening until it covers your nose and mouth.


By roggom at 2011-06-25

I repeated the foam and toothbrush about 3 times, then proceded for a rinse. I attached a small section of garden hose to the drain. My intention was to do this in the garage and catch it in a bucket, but my water hose did not reach so i did it in the driveway. I used an old school twist nozzle, reached through the blower access hole and sprayed the evap coils, I sprayed just a little at a time, giving time for the water to drain out. Again use caution an dont jam the hose into the hole, you dont want to damage the fins or coils, A little pool will develop around the blower shroud, but just do not go crazy with the water.
To remove the pooled water, just use a rage and push it back into the ac/evap drain.

You can see the junk the foam cleaned out


By roggom at 2011-06-25

I then used about 25 gallons of compressed air and blow dryed the fins and whole section and then reassembled and tested it out.

Since the foam I used was lemon scented, the interior had a pleasant smell, I live in Colorado, so everything dried up rather quick. No more frozen pipes or plugged drain and most of all no more vent funk.

AndyEBR

This is perfect! I was just looking at the pressures on my AC and the high side is higher than it should be. First step is to clean the evaporator because EVERYTHING else is new. I was trying to figure out how to get in there and even in the parts diagrams I couldn't see how to get it apart but this should be doable in an evening easily!

Thanks for writing it up!

Andy

investinwaffles

nice dude, my AC has an musty smell too. I was going to try one of ac coil cleaning kits but haven't gotten around to it.


I kind of want to replace my blower anyways because it has a minor bearing noise so I might as well do a deep cleaning at the same time. I did my evap core 2 years or so and had to throw the styrofoam out because it was full of mold.
Bookmarked this for whenever I get around to it