TheExaminer

Sorry for the length, but I want to explain everything first... I had a fogging problem a few weeks ago, so I changed my heater core out. I was glad to do it because I was able to get a new brass/copper one to replace the aluminum one a shop put in last year. It never did get as hot as it should. HC was also not all that hard to replace, nowhere near the nightmare I kept hearing. But, I'm still getting fogging issues, and I noticed it was after I used the fan. We had a chill morning here the other day, so I used the heat a little on the way to work. On the way home the heat was off, but I started getting fog. I'm going to replace the blower motor this week, but while I had it out, I went ahead and pulled the evaporator and dryer with the lines. The system was empty, so I pulled it for a look. I'm thinking the oil in the system MAY have been getting loose near the evap, and when I used the fan, some of it landed on the HC, which fogged me up, or it was getting in the air stream somehow. Is this feasible? And next, I will probably re-assemble the parts just for appearance sake, because I don't want to blow $90 on an AC delete box just YET. Is there anyway to clean the evap out so I can be sure no oil is in it before I stick the lame duck back in? I also don't like the idea of running around with the back of the compressor open (no lines) and the condenser lines open. So I will probably put back in.

sofakingdom

iTrader: (1)

Very eeeeezy to flush the evap.

Pull out the orifice tube. Pour a bit of some totally-evaporating solvent in it: lacquer thinner, denatured alcohol, MEK, acetone, or (horrors!! the right thing!!!!!) AC flush; NOT brake cleaner, mineral spirits, motor degreaser for example. Blow it through with compressed air and a white rag over the end to keep it off your paint. Repeat until it comes out clean. Do the same for the condenser and the metal parts of the lines.

Not sure why you don't want to restore the system to proper operation? Sure as hell makes a car AHELLUVALOT more pleasant to drive in the summer. I realize it doesn't get all that hot in Indiana, but still, a clean NICE car is always better than a filthy s*** bomb all full of BO from sweaty bodies permeating the upholstery.

When you put it back together, do the R-134A conversion. New compressor, ALL the rubber lines (you can wiz-wheel the crimp thingies off of the metal parts and re-use em, just get new A/C hose and hose clamps... DO NOT try to use heater hose clamps, they are FAR too weenie to secure A/C hose), new accumulator/dryer, new orifice tube. Don't use the "right" OT for our cars, instead get the red/orange Frod one, ask for the one for about a 96 Crown Vic.

I'd suspect the windshield fog is because there's still old coolant laying in the ducts. Whenever I do a heater core I always take the parts to the car wash and clean em up before I put em back in, for just exactly that reason.

TheExaminer

Hmm, I'm not sure about there being coolant in the ducts sofa. First, the HC pretty much exploded under a pressure test about 17 mo's ago and flooded the floor with coolant. A shop replaced it with an aluminum, and it worked fine (as much as alum can do) til late May this year. One day I did just what I did the other day--used the heater/blower on the way to work--and when it got hot later at going home time, the heater was off but the glass fogged up so bad I could hardly see to drive. I didn't like that stupid aluminum one anyway, so I was glad to switch to b/c. Again, worked almost perfect until a day I used the heat/blower on the way to work--and it fogged up on the way home. Wasn't as bad this time, not nearly, but it still did it. That's why I don't think it was coolant in the ducts. Too much time passed, and I have hard time believing this brand new b/c core has failed after a couple weeks. At other times I ran with the heat on and no blower just to test it, then switched to bypass and there was no or maybe some microscopic fog. It only fogs when you use the heater AND blower, and it didn't do it for a long time after I got the core replaced. Just seemingly started out of nowhere.

As far as the AC goes, all those components except compressor are out of the car, so no worries about paint. As far as fixing it goes, it gets VERY hot in Indiana, and it's very humid. I just usually drive with the tops out on a summer day. But the main problem is, all the stuff you're talking about replacing costs hundreds of dollars, and I just can't afford to spend like that on the AC now. I'd do it if I could, I just can't. Especially now that I understand how it works a lot better, I'd like to be able to fix it, so maybe later. For now I want to clean it out and put it back together oil free to test and see if I fog up again--so your idea of the solvent is helpful. Although, I don't have an air compressor--I just cant afford all the tools a lot of you guys have. When I get them, I usually have to get one at a time, and far between.

sofakingdom

iTrader: (1)

You've obviously never spent much time in south Louisiana, Alabama, South Carolina, east Texas, etc. You'd be glad for your cool brisk arid summers up there in the frozen tundra.

(my 1st trip through college was at Ole Miss; just got back from Houston yesterday)

Compressor isn't as much $$$ as you might think. Accum is around $35, OT is around $8. Rubber line, enough to do the job, is probably $10, hose clamps another $5 or so. It's really not all that bad, considering how much of an overall improvement in the NICE factor of the car it makes.

TheExaminer

Yeah, that doesn't sound as bad it seemed, I'll put it on the long list of things I need to get done. BTW, I used to live in SC, VA, FL, and AL--but never Texas I'll admit. It IS hotter down there, but here it gets into the 90's with humidity in the 60-75% range, then you freeze your royal butt off in the winter when it gets below zero. It's the worst of all worlds. Anyway, I may pull my compressor off and take it to Autozone. I read online that places like that can test it?

OrangeBird

iTrader: (1)

If you don't have working AC in the car , I doubt any fog your seeing is from oil coming from the evaporator . With no other factors present that could cause such humidity (like soaked carpets from repeated water incursion for ex.) I would have to believe that your new heater core could very well be leaking . Before taking anything apart , a check to see if the cooling system will hold pressure would be good . You don't need to pressurize it any beyond the 14 PSI the radiator cap is rated to vent at . If it holds 14 PSI for an extended time , ok , your fog is from something else . But if it won't hold pressure then yea , your new heater core is bad .

Remember , even brand new out of the box is no 100% ironclad proof that an item will function in the desired application . I have seen brand new starters not crank , brand new alternators not charge , and yes sadly , brand new radiators leak .

TheExaminer

I pressurized it last fall, it held pressure fine and I STILL had a little fog on the glass--just not the ridiculous amount I got in May. Plus, even if it doesn't hold pressure, it's still not a guarantee that it's the HC. Could be leaking anywhere. When I pulled the aluminum one a couple weeks back after the May incident, there was no obvious evidence of leaking coolant anywhere on the HC or in the hvac box, only that fog on the windshield. No smell of coolant either. I'm going to Autozone tomorrow, so I can rent a pressure tester, but it's still a grey area whether or not it's the HC leaking. Getting to my HC is very easy, the hardest part is pulling the map pocket off w/o cracking the plastic. I know new parts can fail, but Im just have a hard time believing it here. This is a heavy duty brass copper core. We'll see.

TheExaminer

Ok, here's more information. I did the pressure test the other day, and as expected, it was inconclusive. The pressure did drop slightly, but part of that is how the tester is held. When I held it still and put the other hand on the cap to secure it, it MAY have dropped slightly, but it was difficult to tell, it would drop microscopically, then it wouldn't. IDK

Now, here is what happened today. I re-installed the lame duck AC components, hand tightened all the connections, and cleaned the windshield fully. I even took the dash pad off and put duct tape over the defrost vents to see what happened! Drove it over 40 miles to work with the temp slider on cool and the fan off. No fog at all, absolutely NONE. When I left work, I started the car and almost immediately the glass above the defrost vent fogged up, and some of it spread to the mid and upper glass--even with duct tape sealing the vents!!! The fog was in a line directly above the defroster. Now, after this initial burst, it did very little the rest of the way home. The fan was never on, and the temp slider never moved off full cold.

One thought I had was that pressurized coolant leaked out as the car cooled, and was turned to vapor once the engine was re-started, but there are problems with this. First, if it was leaking out under pressure, why did it not leak out and fog the glass when I was up to full temp and pressure on the way to work? And second, after sitting for over 8 hours, I don't see how the HC could get instant get hot enough to vaporize liquid coolant in just 2-3 seconds of restart. I don't care to put in a new HC. In my car it's only a minor inconvenience. What I'm more upset about is losing the last brass copper core in the galaxy. I never did like the aluminum one, doesn't work as well.