924Board.org

[cgalyon]

The summer heat is making me think about trying to fix my AC again. I'm honestly not sure why it doesn't work; didn't work when I picked it up and PO didn't seem to know what was wrong with it. I figure the first thing to check is to make sure it's charged. So... this is an '88 924S, what kind of AC system does it use? Can I simply buy a charge kit to recharge it or does it need to be serviced by an expert? What years/models are the parts interchangeable with (so I know where to look for a donor), particularly, is the compressor interchangeable with an '88 944? Thanks!
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1988 924S Navy Blue - Phone Dials

[gohim]

The refrigerant is going to be R12. You can convert it to R134a, but the system is not that powerful even when operating with R12, so expect it to be underwhelming if filled with R134a.

You can still get R12, but you would need a license to buy it. The EPA will license you to buy R12, if you can pass a simple test (written or online), offered by numerous companies (which offer tutoring online and written).

Or you can convert to R12 with a generic kit. No license required to buy R134a, and the refrigerant is less expensive, but you will/should replace more parts than the minimum to get the system to work (as best it can) with R134a.

Either way, you will need to buy an ac manifold gauge set. R12 and R134a use gauge sets with different connectors, so you would need to to a gauge set for the refrigerant you are going to use. R12 gauge sets are slightly more expensive, and getting harder to find. A vacuum pump of some sort to service the ac system. Most auto parts stores with tool loan programs loan the vacuum pump and R134a gauge sets.

Personally, I have R12 and R134a gauge sets (Harbor Freight has R134a sets on sale usually for $40), and an inexpensive (powered by air compressor) vacuum gauge from Harbor Freight ($9.99 on sale).

[John_AZ]

If the PO did not fix it, the system is out of R-12 and by now the compressor main seal needs replaceing. Is there a black greasy oily deposit on the engine pan or the underside of the top radiator hose. If yes this means the oil charge in the compressor has escaped out of the front of the compressor via the main seal.

Compressor/dryer replacement is your best option:
http://www.944online.com/cgi-bin/ASI_Store.cgi?Product+skukey_1206625457+9441+Climatecontrol-9441

You may need additional parts.

You can do a DIY like gohim suggested, or a shop should only charge about $150 for the evac and recharge for R-134A

GL
John_AZ
1988 924S + 1987 924S

[Morrie]

Stick with R12 in my opinion guys. It is still readily available. I am getting it for $15 per 12oz can including shipping and everything. Thats 5 or 6 dollars more than R134 off the shelf... small price for performance. The shop I used had no problem using my R12 instead of charging (pun) me 100 a pound for theirs.

I have a small leak in my compressor, and am planning on doing the kit metioned above as it will also draw less horsepower with the newer rotary compressor, and will probably cool better also. With the stock system fully charged in the Texas heat I am getting fan 2 vent temps down in the 40s which with my tinted windows is keeping me cool. I expect to do slightly better with a properly functioning compressor, we'll see.

Morrie

[bcblase]

My car had been converted to R-134 before I bought it, and I just removed the entire A/C system - if you want any of the parts, I'll send them to you for the cost of shipping.

Everything works, but I had to hack up a couple of the refrigerant hoses to remove them. Compressor, condensor, blower unit, and sensors are all intact.

BC
_________________
1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver

[cgalyon]

I'm going to have diagnostics run on my current setup to make sure it doesn't simply need a recharge. If it turns out that something is broken, then I'll take you up on that offer, BC!
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1988 924S Navy Blue - Phone Dials

[Druman]

Hey guys, quick question: When you recharge the compressor is the "Low" end the one that's right on the compressor and really hard to get to? Also, how many oz. of refrigerant does this take?

I'm doing this to my 944 is there any difference?
TIA


7osh
_________________
87' 924S non-sunroof (Red) 45K miles
85' 944 "early" NA (Red) 130K miles

PORSCHE pisses excellence...

[John_AZ]

If you have R-12 it is about 33oz.
If you converted to R134a it is about 24oz.

Different oils in each. If it is completely empty, you should do a vacuum for 90 minutes and see if it holds.

You charge where you see the big "S" (suction) on the compressor.
On the 944--------you are correct that it is the fitting on your compressor that is impossible to get to. The solution most use is to change the fitting on the compressor to a 90 degree elbow fitting and shorten the AC/alt belt by 1 inch.

http://forums.rennlist.com/rennforums/924-931-944-951-968-forum/514899-i-cant-charge-my-a-c-gauge-doesnt-fit-whats-the-solution-pics-inside.html

The 924S compressor is so much easier....


GL
John_AZ

[Druman]

Thanks Joe Me and another guy got it all figured out earlier today. We couldn't find a place that had a 90 degree adapter so we ended up taking the alternator off, loosening the compressor putting the strait fitting on, hooking the gauge and refrigerant up, bolting the compressor back up but not tightening it, bolting the alternator up with out tightening it, attaching the belt pulling everything tight with some leverage (using a hammer) starting the car and letting it suck in the freon!

It probably wasn't the best way to do it and I wouldn't recommend it to anyone, but hey, I have cold air!


7osh
_________________
87' 924S non-sunroof (Red) 45K miles
85' 944 "early" NA (Red) 130K miles

PORSCHE pisses excellence...

[sbarc]

R-12 and R-134 aren't the only options. There is also ES-12a sold by this website
http://www.es-refrigerants.com/products/w/id/3/default.asp

It works much better than R-134 and is very inexpensive. The above website sells kits. The down side is that ES-12a is somewhat flamable. The gas does have a scent so you know if you have a leak in the passenger compartment. Any leak in the engine compartment would go into the atmosphere.

Here's some comments from an MR2 thread about this......
ES-12a, manufactured by EnviroSafe in Pekin, IL, is THE stuff to get. It is:

1. Non-ozone depleting
2. Non-toxic (well, not severely brain damaging like R-134)
3. Flammable (but not like propane is)
4. It's only a mail order product for most of us
5. You use less than R-12 or R-134
6. It's a petroleum product, so it's molecules are larger than R-12 and R-134 molecules, so it has less chance to leak.
7. It is compatible with almost every A/C oil out there - no need to change oil.
8. For 12 bucks, you can add a can of ProSeal to fix most small leaks.

8. COLD. No, I mean COLD. I HIGHLY recommend the Industrial ES-12a, as it gets colder than the regular version. MR2's will cycle off about 42 degrees F (measured at the center duct). My Lexus SC300 goes down to 31 degrees. The colder it gets, the more efficient it is, and the less it needs to work to get your car cold. My MR2 has will pull the duct temp up to 50 degrees below the inlet temp. R-12 and R-134 will not ever do that.

You can read the whole thread here....
http://www.mr2.com/forums/general-mr2-discussion/Toyota-MR2-6865-r-12-r134.html

I converted my minivan to R-134 and it is pathetic......so I'm definately looking for a better option than R-134 for my other cars.

There's also this stuff......but I have no clue how good it is.
http://www.freeze12.com/

I just wanted to give you some more options to ponder.
_________________
1981 931 (Canadian car)
1981 931 (US car)
1990 928GT (ROW car)
1991 Toyota MR2
1989 Toyota MR2 Super Charged
1985 Toyota Supra
1973 Triumph GT6
1971 Opel GT

[TJC]

We have Freeze 12 in the '87 924S we recently bought. It was installed by a well known Porsche repair shop that the PO used. So far it seems to work quite well.

From what I understand about converting to R134 in the older cars is that because of the differences in how the two types of refrigerants act, the entire system, including the condensor, should be changed over to get anything near the cooling of the old system.
_________________
'95 BMW 318i/5 ..."Pearl"
'87 Porsche 944 NA... "Liebchen"
'02 Porsche Boxster..."Sunbeam"
'04 BMW X3..."Xander"
Still on the Prowl!

www.ttrs1.com

[John_AZ]

If you work on your own AC you can stick anything in the lines.
R12 and R134a are preferred by Porsche.

The other freons mentioned are "install at your own risk"
Most are flamable.

The local automotive AC repair shops will not touch your car if you added a non approved freon because it could damage their equipment and when they evacuate the old freon-----A USA nationwide law, they do not want to MIX freon----because they can clean it up and resell it to you for $60 to $75 a pound--R12.

So go ahead and use Sallys Ice cube Freon if you want.

My 5cents

John

[John_AZ]

[Eska]

[jrrhdmust]

I recently inquired at a shop about converting my 924s to R134, the shop manager advised me against it. He said that the chemicals in R134 and R12 don't mix well, and will eventually cause the compressor to eat itself, and their is no good way to completely flush the system. He siad that he would make more money converting it then just adding more R-12.

This is the first time I have ever heard this. I have comverted 3 cars to date, however all 3 were sold with in a year and half with AC still cold.
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67 Mercury Cougar XR7 under Restoration
71 VW Superbeetle Completed Resto 11/07
73 Mustang Mach 1 10 Year old restoration