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

[wwest]

Originally Posted by Rawknees'Turbo

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?!?!?!

In actuality Charlie never shared that he knew that the schematics were wrong (trade secret I suppose). I set out to prove that the smugglers box relay only powered the front condenser blower, as shown in the '87 schematics, and found out how wrong the schematics are.

[llangston1]

This is first time I have ever had to tap that relay to get the AC to work so that was new wrinkle for me. Like I said earlier that relay is only 3-5 years old and I am pretty sure I bought it from our host. The old original was working fine when I replaced it but it did not have fuse protection hence my decision to replace it. As for the amount of refrigerant left in the system I have to assume it was enough to not trip the low pressure switch but I need to put my gauges on it soon. I was just glad to get it working again. I was not looking forward to a major AC rework this year. I have enough other parts still sitting in their box that need to be put on the car first.

As for the continuing saga or soap opera of AC issues that is what is great about this forum. I love reading the threads and participating when I need to. If Kuehl was down here in Tx he would be a very busy man!

[wwest]

So, why does the 88-89 schematics indicate the use of a binary pressure switch when none are there...???

Shipped only to select countries..??

[Rawknees'Turbo]

Originally Posted by wwest

In actuality Charlie never shared that he knew that the schematics were wrong (trade secret I suppose). I set out to prove that the smugglers box relay only powered the front condenser blower, as shown in the '87 schematics, and found out how wrong the schematics are.

^^^

Langston proved it when he jarred the relay's contact points free, as suggested, and all his inop components (not just the front condenser fan) immediately started working.

[llangston1]

So does that condenser blower relay shown in the '87 schematic even exist? Where is it located?

[Rawknees'Turbo]

Originally Posted by llangston1

This is first time I have ever had to tap that relay to get the AC to work so that was new wrinkle for me.

It's not too uncommon in humid areas, like Houston, for the relay contact points to develop corrosion and stick together when not in use for any length of time.

[llangston1]

I removed my bowtie vent below my dash and wonder if anyone knows of a decent remote sensor bulb type temp gauge that could be used by sticking the sensor/bulb in the bow tie hole and the gauge in the ash tray or console and viewed when necessary? The AC temp gauges I have now never want to stay in the vents unless wedged in and then they may be reading vent structure temps rather than air flow temps.

[wwest]

Originally Posted by llangston1

This is first time I have ever had to tap that relay to get the AC to work so that was new wrinkle for me. Like I said earlier that relay is only 3-5 years old and I am pretty sure I bought it from our host. The old original was working fine when I replaced it but it did not have fuse protection hence my decision to replace it. As for the amount of refrigerant left in the system I have to assume it was enough to not trip the low pressure switch but I need to put my gauges on it soon. I was just glad to get it working again. I was not looking forward to a major AC rework this year. I have enough other parts still sitting in their box that need to be put on the car first.

As for the continuing saga or soap opera of AC issues that is what is great about this forum. I love reading the threads and participating when I need to. If Kuehl was down here in Tx he would be a very busy man!

All of the loads represent an inductive load, plus the 2 motors will have a HIGH inrush current at startup, that can be really hard on electrical switch/relay contacts.

That 80 PSI on both high/low should easily be enough to overcome the low pressure switch cutout.

[llangston1]

Good point RawKnees, I have not driven the car very much and we have had our share of humidity this year already with all the rain and flooding. I sometimes am amazed that it still cranks and runs as well as it does. Knock on wood!

[Corvus Corvax]

Originally Posted by Rawknees'Turbo

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?!?!?!

Seriously. Pieholio won't get action because there aren't enough complaints, or to the right person. Or the moderator of this group is just much more laid back. Doesn't matter.

Provide good info, don't rise to the bait of the troll, and don't post goat pr0n in the Marketplace forum.

[Corvus Corvax]

Originally Posted by llangston1

Good point RawKnees, I have not driven the car very much and we have had our share of humidity this year already with all the rain and flooding. I sometimes am amazed that it still cranks and runs as well as it does. Knock on wood!

Have you taken the relay apart and looked at the contacts? One of the things I did with an older relay was I took off the cover and squirted some Deoxit in there, and let the solvent evaporate. Put the cover on, and the relay has not stuck since. Worth a shot, and Deoxit is good to have for other uses. I rehabilitated a switch or three with the stuff as well.

[llangston1]

No I have not tried to take the relay apart and inspect or clean it. That is a good idea since it is relatively easy to get access to it. thx for the suggestion.

[wwest]

What we used back in my USAF days... late fifties.



http://www.newark.com/jonard-tools/ob-1-3/burnisher-fine-contact-blk-pack/dp/61X9368?CMP=KNC-GUSA-GEN-SHOPPING-NEW-JONARD-TOOLS&ad=81515567661&gclid=CLyA8JrSsMwCFc1hfgodHRsBBQ

[Rawknees'Turbo]

Originally Posted by Corvus Corvax

. . . and don't post goat pr0n in the Marketplace forum.

Sir, you ask too much!!!

[kuehl]

Originally Posted by llangston1

So does that condenser blower relay shown in the '87 schematic even exist? Where is it located?

The front condenser blower motor relay is located in the primary fuse/relay panel in the front trunk, like #6 , closest to front bumper. When the AC thermostat calls for 'demand', its contacts 'make' (close), the relay turns on and powers the blower motor. When AC thermostat contacts 'break' (open) power is cut to the motor.
Ditto same time this happens to the compressor clutch.





excuse the poor image, it was left in the toaster


And, its "official" iwhelan's thread was hijacked. Bob, you care to comment on that? Have we violated the rules?
Is it time to send in lawyers, guns and money?

[kuehl]

Originally Posted by wwest

In actuality Charlie never shared that he knew that the schematics were wrong (trade secret I suppose). I set out to prove that the smugglers box relay only powered the front condenser blower, as shown in the '87 schematics, and found out how wrong the schematics are.

masseur wwest,
i have in the past, on another thread, noted P had a pressure switch (can't say its binary, certainly it ain't a red dot trinary) drawn in their later year schematics. The schematics are public knowledge (found in shop manuals as well as the world wide webster). Doubt you'd find them in Wiki, probably they have been under the control of NSA, or in the NIST library; you could have filed a form Form G-639 at any time you know.

[wwest]

Originally Posted by kuehl

masseur wwest,
i have in the past, on another thread, noted P had a pressure switch (can't say its binary, certainly it ain't a red dot trinary) drawn in their later year schematics. The schematics are public knowledge (found in shop manuals as well as the world wide webster). Doubt you'd find them in Wiki, probably they have been under the control of NSA, or in the NIST library; you could have filed a form Form G-639 at any time you know.

Yes, the "schematics" are public knowledge...

Does anyone have access to ones that are actually correct...??

It seems that the wiring in my '88 does not compare to any of the various publicly accessible schematics.

[kuehl]

Originally Posted by wwest

Does anyone have access to ones that are actually correct...??

It seems that the wiring in my '88 does not compare to any of the various publicly accessible schematics.

Are you having issue with your AC system ?

[Corvus Corvax]

Originally Posted by wwest

Yes, the "schematics" are public knowledge...

Does anyone have access to ones that are actually correct...??

It seems that the wiring in my '88 does not compare to any of the various publicly accessible schematics.

Wild West, you have made it clear in the past that you wish to show Griff as being wrong. The problem in this thread is that you've been tripped by your own hubris and the fact that the Germans are crazy. Your descent into the realm of the Dunning-Kruger Effect is highlighted here because you have forgotten the time honored tradition of the TSB. Without fail, the Germans make running changes in production, and the changes sometimes take a very long time to filter into bound print editions of even workshop manuals. Technical service bulletins are loose-leaf and sometimes aren't made available to the general public. This is especially true in wiring diagrams. It's almost guaranteed that the wiring in your car doesnt match the Bentley. And, crazy enough, the different export versions might be wired differently! Here's the point. Charlie knows more than you on this subject. You should take him at his word when he tells you how the electricity flows on an aircooled Porsche AC system. Nobody knows more than he does on this subject. I know, from reading what you've written before, that none of what I've written here will matter to you. But others will see it and get a clearer picture. Be well.

[rokemester]

Well said. Thanks.