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Loose rivets
24th Dec 2006, 17:34
We had some beautiful weather t'other day, but it got a tad too hot and I suddenly had the urge to mess with the A/C on me old car. I'd been putting if of for weeks cos the only bloke that is interested in buying the car would have taken it without the job done. However, 31c and I was moved to act.

I went to AutoZone and paid the full price for a vacuum pump and gauges, some $300. The astonishing part is that I got a full refund when I took back the ‘loaners'.

I know little about A/C being a Brit, but a little more than I did 2 years ago and what I do know is that if you are lucky one can save $1,000s. Many years ago my daughter sat in mt BMW surrounded by a white cloud of Freon.... "Oooo, bad that..." Engineer sucks teeth. "Mumble mumbe hundreds....mumble mumble, £1,000 or so."

I went to HoseQuip in Colchester and they made me up a pipe using the existing ends. 4,000 psi hydraulic pipe....that should do it. £20 Industrial estate A/C folk .... £15 for gassing it up. It wasn't bad, but I didn't know too much about things then. They hadn't vac'd out the system properly.

This time I needed to flush out the crappola that I had been sold to detect leaks with UV dye. DON'T DO THIS. It will goo up the system.

This is a dryer. Not much in it except a wire gauze filter and two bags of silica-gel (or some such)

http://img.photobucket.com/albums/v703/walnaze/Dec1506003.jpg

One I did earlier. You may see the green goo on the sacks.

http://img.photobucket.com/albums/v703/walnaze/DashboardDec1506006.jpg


I removed the orifice, a tiny 2.5" object from one of the pipes. It was choked up on the upstream filter. You can just see the tiny tube to the right of the O ring inside the square holes.

The entire energy of the compressor is forced through a tiny hole in this inner pipe. Energy that slows down a 5.7 ltr V8 !!! This part was $1.98

http://img.photobucket.com/albums/v703/walnaze/DashboardDec1506008.jpg

I used some expensive stuff to wash out the radiator/condenser and the evaporator. $20 for a liter. Acetone would have done I think, but I didn't want to confuse the issue with variables. The only difficult part was making bits of plastic hose fit over the pipe ends. Leave for half an hour or so.

Never wash towards the compressor they told me. Makes sense.

Having blown the wash into Ziplock bags, I ran the airline into the system for some minuets, purging all of the crappola that would come out. Great care has to be taken of the inner heat exchanger, cos if you pop that, down here the car is a write off. Yep, it's that difficult to change. Could sell it to a Canadian I suppose.

Now, having put on the new dryer can, introduced the 8oz of lube and re-assembled, I had to purge out the air and in particular the water vapor. The half horse pump was left on for over an hour. I never got much more than 20" Hg vac, that was disappointing. 23 was my aim. This causes the water droplets to vaporize still, without circulation, how is the system supposed to be cleaned of vapor? My guess was an intermediate shot or two of 134a, the Freon type stuff used now.

Tiny bubbles kept coming out and hour after starting.

http://img.photobucket.com/albums/v703/walnaze/DashboardDec1506005.jpg


To get things moving I shorted out the Low pressure switch on the side of the dryer. This enables the compressor. 1500 rpm and air forced into the front rad is needed and a set of tables off the Caddy forum gave me 70% humidity and 80f = 34 psi low and 340 hi side. It took ages getting the stuff in from 3 small cans. As the rpm goes up the pressure goes down, so more vaporization in the tin. Ice formed on the tin...a good sign that it's going in.

Slowly water droplets formed on the cold pipe, then a drip or two from the cab drain ... at last a steady flow. Something had to be right, even with 70% humidity.

Well, it's colder than it's ever been, but I'm sure that the only real fix would have been to replace the compressor as well. Mucho work and $200 on e-bay. Still the old one has a date of 02, so I'm hoping with everything crossed.

arcniz
24th Dec 2006, 20:14
Brave project, plus solid documentary. Bully good job! Merry Xmas!

flowman
24th Dec 2006, 21:50
Paid 800 quid to have the A/C fixed on an old Jag I had. Sounds like a bargain!
You're a better man than I !
(The only function for A/C in this part of the world is to stop the windows misting uo when it's drizzling!):*

Lancelot37
24th Dec 2006, 21:59
Paid 800 quid to have the A/C fixed on an old Jag I had. Sounds like a bargain!
You're a better man than I !
(The only function for A/C in this part of the world is to stop the windows misting uo when it's drizzling!):*
-------------------------------------------------

Why do air conditioning systems fail in most cars? Because they are not left ON all of the year. I know cars that are 15 years old in Australia and they have never been serviced as they didn't need it.

If air con is only used intermittently the seals dry out, the gas escapes and you have an expensive bill. It could cost you a thousand pounds.

Leave them on, and if they are not Climate Control where you can set the temperature, you simple blend in some warm/hot air as needed.

Aaaaaaaaaaaaaaaargh!
24th Dec 2006, 23:50
Leave a/c on all year ifyou want, but you'll pay for it in gas mileage. Good point, but maybe just run it once a week.

NIGELINOZ
24th Dec 2006, 23:54
Quote:Leave them on, and if they are not Climate Control where you can set the temperature, you simple blend in some warm/hot air as needed."
Absolutely correct.Here in Australia I drive a 1985 Falcon (very similar to a Granada) which has done 450,000 kilometres and the air conditioner still works perfectly even in days of plus 40 Celsius.
I use it during winter by adding warm air from the ventilation system,it stops the windows misting up and keeps the A/C working well in preparation for our scorching summer.

vapilot2004
26th Dec 2006, 07:03
Nice project you have going LR. Looks like excellent work from here. :ok:

That orifice tube when clogged will cause the evaporator temps to stay well above freezing in hot weather. Another telltale sign of this condition is a lack of compressor cycling on moderately hot days.

Regarding AC seals - wintertime use of the compressor is limited to above freezing temps by a cutout when on automatic while Econ will prevent the AC compressor from running at all. Many already familiar with cold and damp will surely appreciate the defog function of the system.

Good advice to engage the AC a few times a month if you have the outside temps for it.

planepsycho
26th Dec 2006, 11:35
LR, how many bedrooms does that car have?:E;)

Loose rivets
26th Dec 2006, 19:54
Just the one http://www.augk18.dsl.pipex.com/Smileys/2-sly.gif

sprocket
26th Dec 2006, 20:29
Interesting blog Rivets, alas, in OZ some new regulations make it a lot harder for the layman to obtain refrigerant gas R134. The green groups have convinced the govt. that aircons are the reason for the ozone depletion in the atmosphere (I have my doubts about that one).

the Australian Government's Ozone Protection and Synthetic Greenhouse Gas Management Act 1989 came into effect on 1 July 2005. The regulations affect those who buy, sell or handle ozone depleting substances or synthetic greenhouse gases.
Persons who handle these substances in bulk or in equipment are required to hold a licence.
Companies or persons who acquire, possess or dispose of these substances are required to hold a refrigerant trading authorisation.



... the old gas remaining in aircon systems being serviced have to be removed (no more releasing into the atmospere) and stored in containers for recycling. The amount of new gas put into an A/C system has to be measured and recorded.

Lancelot37
26th Dec 2006, 20:37
Leave a/c on all year ifyou want, but you'll pay for it in gas mileage. Good point, but maybe just run it once a week.

If you are so short of money you should not have bought a car with air-con. You must be a very poorly paid pilot.

Modern systems use less than 1 mpg to run the air con.
By all means switch it off, but be prepared to pay £1,000 ($1,500) to repair it.

Rick Storm
26th Dec 2006, 20:47
Loose Rivets
Well done on the a/c but in the photo your rear n/s tyre looks under inflated you could roll the back end.

frostbite
26th Dec 2006, 21:34
in OZ some new regulations make it a lot harder for the layman to obtain refrigerant gas R134.


It's not that long since (in the UK) they banned R12 and told us that R134 was the answer to the 'green' problem!

click
26th Dec 2006, 23:27
Impressive!!! I had a Chrysler Lebaron and every year, in the spring I had to go to Crappy Tire (Canadian Tire, sort of home depot for cars) and get a can of R12 to fill the system. Bought a can for 5 bucks, hooked up the rinky dink adapter and let her rip. Until one day when, to my great surprise, no more crappy tire cans. The acne faced kid just turned and said no more, it;'s the law. So I did what we do when things get banned and crossed the border to Buffalo NY. Strolled in to a Pep Boys outfit and called out 'hey guys- got any R12? Never seen people peed off so quickly and basically they showed me the door...they thought it was a sting operation. To finish the story, I finally got a can, for 20 dollars, bought 2 right away and I think I overfilled the system because it worked real good for a while and then the exchanger got all iced up and no more cool air.

sprocket
26th Dec 2006, 23:29
Frosty, thats what I thought when 134 was introduced here some years back. Methinks someone is pulling wool over politicians eyes, as usual.

Loose rivets
27th Dec 2006, 00:23
Yes, R12 is licence only here. There is an R12 replacement, but it's best to change the connectors and put in 134a. There is a slight loss of efficiency as the 134a is not as efficient. The newer systems had to be upgraded to cope with the lesser gas, but a changed one is better than nowt. (Circa 1995, so the green thing I'm driving now just scraped in with the new gas.)

The trouble is, that so many people just accept leaky systems: topping up is the norm. Bad that.

Funny thing is that I'm off to Canada on Thursday. Been buying thermals and fox-hats.

av8boy
27th Dec 2006, 03:48
On a (perhaps un-) related note...

The daughter reported that sweetish-smelling liquid was dripping on the carpet on the passenger side of her Ford Escort. I diagnosed heater core failure.

In that it was summer, I simply detached the heater hoses from the core on the engine side of the firewall and put a length of copper tubing between them. Problem solved (in the short-term). I also went to the auto parts store and acquired a new heater core.

Well, the seasons being what they are, even in Northern California, Fall came with the attendant window fogging and daughter's cold fingers. I was pressed into action.

Never fall for this.

To replace the heater core in a mid-90s US Ford Escort is an excercise in frustration. It requires the removal of the entire dashboard. Not just the instrument panel, but the entire dashboard.

Two days it took me to get through this. I kept reminding myself that this was saving me some $500 in labor costs, but that number lost its appeal early in the process. Here's a picture of the car just before the half-way mark:

http://www.atcmuseum.org/images/escort_interior.jpg

That thing in the foreground is the dashboard.

What a frigging nightmare. I'm done being the guy who can fix anything.

Although it worked out great and apart from a busted glove box everything's just fine, I'm done. I'm just thankful I didn't have to do this in Winnepeg.


Dave
:ugh:

Loose rivets
27th Dec 2006, 07:00
Mmmmm......braver man than I. I sold my Chevvy Blazer with no heater...to a Mexican family. "I'll give you the new 'coil' " I said..."but frankly, I would just connect it in the winter and leave it lying on the floor or parcel shelf."

Just taking out the instrument cluster (150 odd dry joints on the digital dash) was a day's work. Kinda satisfying when done though.

This is all about doing it...not the end result.( I keep telling myself. but then I am prone to talking bo-lox :hmm: )

Loose rivets
27th Dec 2006, 20:00
Loose Rivets
Well done on the a/c but in the photo your rear n/s tyre looks under inflated you could roll the back end.

Good call on the tire...thanks. I check the car over if it's going out of town, but just lately it's been languishing in the garage. It was down to 22 psi