A/c Question

SPIKES · 06-11-2003, 06:02 PM

my 85 carrera a/c loses coolness quickly.
still working but i thing loosing freon.

is there a "trouble spot" where these a/c's are known to loose gas on theses cars?

thanks

radcon · radcon's Garage

If you have a York reciprocating compressor, it's very likely that the seal is shot.

SPIKES · 06-11-2003, 06:33 PM

THANKS RADCON
not sure what unit i have. will check tommorow. do i check for oil discharge somewhere or is it internal?

radcon · radcon's Garage

If your seal is seriously shot, you may notice some oil splatter on the underside of your decklid.

Jim Sims · 06-11-2003, 06:44 PM

Does the A/C unit work for a while after you turn it on and then it blows warm for awhile and then back to cold and so on? Jim

stuartj · 06-11-2003, 07:14 PM

You have airconditioning? Sheesh

88911coupe · 06-11-2003, 07:17 PM

The constant flexing can cause leaks in the connections to the rear lid condensor. However, make sure and look at the underside of the rear lid to see if there is oil spray there. That's a sure fire sign that the compressor seal is shot. There are kits now (see Pelican) that can be used to fix this without having to buy a new one.
Good Luck,

SPIKES · 06-12-2003, 04:52 AM

THANKS GUYS
yes it runs cool all the time but not cold.
got the car last week and the worshop gassed it as they said it was not cold.
this lasted for a day....it all works but is losing freon.

i will check all connections and seals as has been suggested.

GREAT FORUM BY THE WAY!

i had my previous porsche about 5 years ago in south africa and there were no forums. you had to rely on the "mood" of the local wrench for help.

THANKS

SPIKES · 06-17-2003, 08:47 AM

Quote:

Originally posted by SPIKES
THANKS RADCON
not sure what unit i have. will check tommorow. do i check for oil discharge somewhere or is it internal?

the unit is a nipondenso? is this a later unit???
no evidense of oil leaking out.
put in 1 can of freon and you can feel the pipe at the compressor getting cold immediately.
the a/c runs cold but after 2 days it is warm again.

any other places to find the leak?

nhromyak · nhromyak's Garage

My '85 leaks at the front condensor.... I can see the oil splatters.

SPIKES · 06-17-2003, 02:18 PM

Quote:

Originally posted by SPIKES
the unit is a nipondenso? is this a later unit???
no evidense of oil leaking out.

jdowty3 · jdowty3's Garage

The Nippondenso compressor is just a different factory installed unit than the York. Replace it with a Sanden or Seiko-Seiki unit. Any shop that does AC service can leak test the connections for you. You don't say if your using R12 or 134. If your using 134, adding more freon will change the chemical balance that allows 134 to work semi-efficiently. 134 is a mix of chemicals and they leak out of the system at differing rates. Also, each can will add more oil to the system until you end up with more or than freon.

SPIKES · 06-18-2003, 02:56 PM

what should the temp. be approx. at vent. when the a/c is cool. after regas it runs at about 65 degrees and outside temp is about 80 and before re-gas temp is about 74 degrees.

thanks

b.t.w.: silly question....i notice the front fan in the trunk that fits over codenser is dead. HOW much diff. does this make to a/c?

jdowty3 · jdowty3's Garage

the biggest problem with pre 964 - 993 AC is the lack of condensor area and poor air flow for heat transfer. Best upgrade is probably replacing the front and rear condensors with a 993 fender mount unit. Another option is to install a under mount condensor which is what I did. If thats not an option, definately fix the front fan. I am just about to have my system evacuated, leak tested and charged. I expect vent temps in the low 40's.

88911coupe · 06-18-2003, 04:01 PM

Has anyone documented using the 993 conversion on a Carrera...with pictures and what had to be done/removed, etc?

SPIKES · 06-18-2003, 04:32 PM

i am confused with components.

rear of car- a/c compressor
rear deck lid- evaporator or condensor?
front trunk- expansion vave in cavity.
- blower motor in front of battery
front wheel well- a/c drier
front of car underneath - evaporator or condensor?

please help with terminology and correct components.

thanks

jdowty3 · jdowty3's Garage

the 911 has 2 condensors, 1 in the front with a fan and 1 on the deck lid which is cooled by air coming in to the engine for intake and cooling.
there is a drier/accumulator behind the front drivers tire and the evaporator (with the expansion valve attached) in the smugglers compartment in the trunk. You can add a 993 style condensor to the wheel well in front of the drivers side tire (you have to relocate the windshield washer tank) and/or mount an under belly condensor on the bottom of the car in the area where the seats mount. The Freon pumps from the compressor under high pressure and temp thru the 2 condensors, then thru the drier, then thru the evaporator (where the cooling happens) and back to the compressor. Bottom line is a 911 needs a condensor upgrade, barriers hoses, and a Sanden or Seiko-Seiki compressor to really cool well in hot weather. I belive the condensor upgrade will make the most difference in getting cold air.

SPIKES · 06-18-2003, 05:19 PM

thanks jim

kepperly · kepperly's Garage

Take out you owners manual and look up the service procedure for recahrging you car IF it is still equiped with R-12. You need two friends to help. one to watch the site glass under the yellow cap on the filter dryer, one to hold the rpm at 2000rpm and one to watch the freon can in the engine bay. When the red ball floats to the top of the site glass its charged properly. Need freon? email me keithepperly@earthlink.net

keith- 87 slant nose cabriolet wide body carrera w/ cold a/c

ruf-porsche · ruf-porsche's Garage

You need to keep the rear lid down or have a fan blowing air over the rear condensor or else the high side pressure will be to great. You will either pop a line or condensor or maybe the compressor.