'87 911 Air Conditioning questions - Yes, another A/C thread!

[Pazuzu]

Originally Posted by wwest

Puzzling...

The schematic diagram I posted is for an '85 911..

Kuehl's link is to an '82....

llangston1's 911 is an '87....

It's not puzzling, your hand drawn wiring diagram is wrong or not clear. The relay in the smugglers box is powered from a fuse in the frunk. It's triggered by another fuse against the starter motor wiring (so it shuts the system down when cranking). It feed direct power to switch on the dash, which then feeds power to the evaporator motor, temperature switch, clutch and the trigger side of the condenser relay. So, it has one big motor, one big electromagnetic clutch, some small switches and a relay trigger on it. Not trivial.

[llangston1]

The relay on the car now is one I believe I purchased from Pelican that had a fuse built into the relay. My original relay did not. I will say that at some time in the past this relay has gotten pretty hot ( maybe when my previous compressor clutch shorted out) such that some the plastic housing surrounding the spade connectors had melted.

[kuehl]

Pazuzu is correct.
The old SC schematic has not changed much in the Carrera,
and you will find one Carrera schematic that shows a pressure
switch the factory never installed.

As far as the relay goes, the older metal can relays had a higher amperage
rating, the new ones sold do not; I believe Porsche kept the same part number
(which is not common) and changed the relay (added a fused and dropped the amp rating). Get yourself a 30-40 amp relay (they are common).
Just cause it says P on it does not mean its perfect.

[Corvus Corvax]

Originally Posted by kuehl

Too bad Eric and Ron aren't here to help

Both of those stupid e-tards got canned by a PP Uberfuehrer. So they can't help. But in this case, you have it right on the higher amperage and fused relay. There is a lot of stuff and a lot of wire on that circuit. And absolutely P<>perfect. There are very good aftermarket suppliers of electronic goods, and the manufacture of such goods has improved some in the last 30 years.

[wwest]

Went to another source for 86-87 911 A/C schematic diagrams, no second relay for clutch,same as posted.

[Bob Kontak]

Originally Posted by wwest

Not all model years included a damping diode at the compressor clutch connection

In 2010 some asshat named Charlie said to you, and I damn near quote "How would the OP know what OAT means"?

You talk out of your ass with wind that is not applicable to any routine issue.

FOAD. I mean die. Literally.

You are an empty, pathetic man without value even within the sliver you deem yourself a demigod.

How is this allowed to happen?

[Bob Kontak]

Did you scan that picture with a toaster, Willy?

[Bob Kontak]

God damn it. How is wwest allowed to pollute this forum again? Where is Black993, a real moderator, BTW, when we need him?

[wwest]

Originally Posted by Bob Kontak

God damn it. How is wwest allowed to pollute this forum again? Where is Black993, a real moderator, BTW, when we need him?

Bob, why does providing FACTUAL information constitute pollution...?

[llangston1]

So the box labeled Air Conditioner Relay in the 86-86 diagram must be the one in the smugglers box. Before I tapped it yesterday I had no evaporator fan blowing at any speed, no fender condenser fan running and no compressor engaging. After I tapped it everything began to work and proceeded to work as long as I drove the car around. I have not tried it today so I don't know if it will continue to work. Not sure where the front condenser relay is located but I do have a separate fuse on that component as recommended.

[Bob Kontak]

Lemmie check what you posted when I get home. Old habits die hard.

[kuehl]

Ya gotta love these AC threads:

iwhelan = missing in action
llangston1 = keeping a hammer in glove box to bang the relay
dave's= in the easy chair
Rawknees'Turbo - wins the Pulitzer
Corvus Corvax - go pound salt
Bob - searches the bleachers for the moderator
West - made parole but lost but lost his bifocals
Mike - compos mentis
Irhmsd & darrin - ran out for bagels
sonett43 - tosses a hail mary, of course I fumble it
dentist90 - time to turn up the N 2O.

[wwest]

Better toaster:

[kuehl]

Amazing, where's the pressure switch!

[wwest]

Originally Posted by kuehl

Amazing, where's the pressure switch!

Yes, "where"...

Not in my '88

971-4 chart indicates that the high pressure switch was NOT used '84-89.....

[dentist90]

Originally Posted by kuehl

Ya gotta love these AC threads:

iwhelan = missing in action
llangston1 = keeping a hammer in glove box to bang the relay
dave's= in the easy chair
Rawknees'Turbo - wins the Pulitzer
Corvus Corvax - go pound salt
Bob - searches the bleachers for the moderator
West - made parole but lost but lost his bifocals
Mike - compos mentis
Irhmsd & darrin - ran out for bagels
sonett43 - tosses a hail mary, of course I fumble it
dentist90 - time to turn up the N 2O.

Ahhh, the usual suspects. You forgot to add Charlie- too kuehl for skool

Back to my huffin'....

[DaveMcKenz]

Originally Posted by llangston1

Thx for the tips. I had used the cup of ice trick when I first rebuilt this AC system a few years ago and the thermostat switch worked OK then. Also I finally got my gauges on the system today and got this reading without the motor and compressor running. It seems like both the hi and low sides were indicating about 80 psi. I have not tried to get a reading with the engine running yet. I need to get the compressor to engage before that. Here is a pic of the static gauge reading.

Glad you solved the relay problem by tapping it with your fist. Sounds like time for a new one.
BTW a static charge of 80 only says there is at least a little refrigerant in the system. It may be almost empty and show the same static charge depending on OAT.
Good luck,
Dave

[wwest]

Damn..!

A big shout-out, KUDO's to Kuehl/Charlie.

The relay in the smugglers box provides power to the front condenser blower, the evaporator blower, and the compressor clutch via the thermostatic switch.

All known, to me, schematic diagrams are apparently wrong.

[86 911 Targa]

Originally Posted by Bob Kontak

God damn it. How is wwest allowed to pollute this forum again? Where is Black993, a real moderator, BTW, when we need him?

I use the ignore list.....

[Rawknees'Turbo]

Originally Posted by wwest

Damn..!

A big shout-out, KUDO's to Kuehl/Charlie.

Whoda' thunk that a tremendously experienced, bonafide expert in Porsche a/c (and mobile a/c in general) actually knows what he's talking about, right?!?!?!