Help needed with AC

[Eric1973]

Hi everyone,

This is my first post so I’ll try to introduce myself a bit. My name is Eric, from Geneva, Switzerland. I inherited from my late father a 1987 911 coupé a bit more than a year ago .

My father got it second hand in Italy in 2006, it is full matching number, Prussian blue and around 100k miles ( 156k Km). The condition is overall very good, the paint is like new, , no rust, interior has its age but is overall in good shape but I do have a few issue which I try to fix now and then. So far, I managed, with a bit of help from the forum to get the sunroof working again ( the usual issue with the cables that snapped), get rid of the alarm that was installed in the 90s ( very badly done, ugly wiring and a big mess in the electrical system). I still have a few things to do, but my main concern today is related to the ventilation and AC

It seems like the AC has been modified in a number of ways, both electrical and mechanical. The compressor seems to be original ( SEIKO SEIKI) but the condenser blower is not ( SPAL CORREGIO, from Italy) the wiring to the clutch is running alongside the refrigerant hose ( right side under the car), the back radiator is 2 third of the size It should be, the relays for both the condenser blower and the front blower are hanging around next to the fuse box and as it can be seen on the picture, the piece that connect the condenser blower to the pipes has been changed to a very strange piece with 3 outputs instead of the original 2. I don’t know what was the purpose of the modifications, maybe a kind of improvement for the hot Italian weather?

So far, every component seems to be working fine ( fans are ok, relays do their job, the clutch engage when hot-wired). I managed to bet the air temperature knob to move again ( it was completely stuck) but I’m not really sure of how it is supposed to work. What seems to be a temperature probe goes to it and when I check the circuit between the 2 other pins, I get always the same resistance, whatever the position of the knob.

The fluid circuit seems to has some pressure to it, I cannot however tell if it’s ok or not.

Unfortunately, I don’t have any AC, when I turn the switches on, unless the fan running, the clutch is not engaging, and therefore no cool air ( or at least no information about its level of efficiency.

I noticed that the clutch wire is connected to the desiccator and I guess the circuit is let open from there.

Of course, I’d love to get the AC to work again, and as well clean the mess with the wires, relays and ventilation hoses ( the connector piece replaced is not available to buy anymore, if I cannot get a second-hand one, I’ll 3D print it).

What do you think I should do? Change this evaporator first, see if the system is working and work on the rest form there? Or maybe go for a retrofit with a complete cleaning of the system and put new seals and modern gas ( the compressor states “R12” on it).

It would be very kind of you as well if you could send me some pictures of where I should install the relays and how the clutch wire is travelling through the car ( I guess running underneath next to the gas hose is not the best option)

To be a bit more explicit, here are a few pics of the configuration

Looking forward to your help

Eric

[jjeffries]

Eric, the best resource for Porsche AC info, in my opinion, may be found at www.griffiths.com. Mr. Griffiths runs the best shop for us to buy replacement AC parts, but also freely shares an incredible amount of technical and diagnostic information.

Best of luck,
John

[pavegeno]

Second for Griffith's. When I decided to get my 1988 air conditioning working, I replaced everything with Griffith's products including the barrier hoses, two extra condensers in the left rear wheel wellness front and rear condensers, the additional vent to replace the bow tie vent behind the center console, rcvr/drier, expansion valve, variable fan speed controller, and the hurricane fan. Fifteen years later it is still pumping out vent temps of 32-34F (0-1C) and keeps me cold and comfortable.

Good luck!

[GH85Carrera]

I will agree, if you want a AC system that simply works, he can set you up.

I have the full boat system 4 condensers, hurricane fan, variable speed controller and extra vents in my 85. I was out in the insane heat of southern California, Arizona, and New Mexico for 10 days. 107 degree heat, and I was getting 37 degree cold air and staying cool inside the car.

Fixing other people's changes can be a challenge. Good luck, and enjoy your 911!

[Eric1973]

Thank you all for your replies,

I had a look earlier this week on Griffith's website looking for conversion kits but didn't notice their help section, very informative.

After a deeper look this morning, what I thought to be the thermoswitch is actually the high/low pressure switch, located on top of the dryer can, the circuit staying open, I don't know if it's because of a lack of gas or the switch itself. By bypassing the switch I got the clutch to engage properly and it seems to make a bit of cold ( I run it at 2000 rpm for a few mins).

As there is still some gas in it after many years ( didn't find in the invoices any related to recharging of gas in the last 20 years). I guess the gas circuit is ok.

In any case I need to change the dryer can, it is awfully rusty and the switch cannot be trusted. I will then go for a conversion kit ( seals, new oil and dryer) and get it refilled. Hopefully, that might get it to work fine.

My other concerns I still couldn't find any answers for are these wires and relays issues. Where should they be? . I found a picture of a smuggler's box with a relay in it, I guess this is where they belong to, but what about the wires, which path do they follow from the pressure switch to the clutch?

Eric

[Eric1973]

My previous message from this morning doesn’t seem to have been published….

Thank you for your replies, I had a look a few days ago at Griffith’s website but didn’t see their help section. Very helpful.

What I thought was the temperature switch is actually the pressure switch, and it seems either to be inoperative or the pressure is too low.

By bypassing the sensor switch, I managed to get the AC working, only for a few minutes as I didn’t want to damage the compressor in case I don’t have enough fluid in the system.

This afternoon, I carried on my searches and came to the conclusion that the AC was not installed when the car was produced ( which after all my discoveries makes sense), which is very strange because it appears in the options codes on the sticker in my warranty booklet ( I know that these could contain mistakes in these times)

I don’t really know what to do, having an AC is obviously a bonus (although it is only used a few days a year in our area) and at the same time, I’d like to keep it as much original as it should be.

What annoys me the most is that in order to install this aftermarket AC they had to cut out the fuel tank support holder for the front condenser and in case I’d decide to get rid of the AC, I’d have to get this fixed. Considering the car is in almost perfect body condition, I’m a bit reluctant to go for what I suppose is quite costly repair.

What do you think is the best?

Eric

[blue911rsr]

Just have the system charged by bypassing the evaporated temp sensor which is probably bad
You can probably use a factory part for like a USA model to replace it
Put about 2.5 lbs of r134 a in it and see how it works
Maybe add 2 ounces or so of compressor oil as well
Once it’s working check make sure front fan is working and check for leaks all very simple stuff
Hope this helps

[RSTarga]

That looks like the rear condensor for a 930 as it had to share space with the intercooler.
Don't add R134 since your car probably still has R12.
Griffiths is your best bet, good luck.

[GH85Carrera]

Originally Posted by Eric1973

My previous message from this morning doesn’t seem to have been published….

Thank you for your replies, I had a look a few days ago at Griffith’s website but didn’t see their help section. Very helpful.

What I thought was the temperature switch is actually the pressure switch, and it seems either to be inoperative or the pressure is too low.

By bypassing the sensor switch, I managed to get the AC working, only for a few minutes as I didn’t want to damage the compressor in case I don’t have enough fluid in the system.

This afternoon, I carried on my searches and came to the conclusion that the AC was not installed when the car was produced ( which after all my discoveries makes sense), which is very strange because it appears in the options codes on the sticker in my warranty booklet ( I know that these could contain mistakes in these times)

I don’t really know what to do, having an AC is obviously a bonus (although it is only used a few days a year in our area) and at the same time, I’d like to keep it as much original as it should be.

What annoys me the most is that in order to install this aftermarket AC they had to cut out the fuel tank support holder for the front condenser and in case I’d decide to get rid of the AC, I’d have to get this fixed. Considering the car is in almost perfect body condition, I’m a bit reluctant to go for what I suppose is quite costly repair.

What do you think is the best?

Eric

Griffith's helps his customers with simply THE best instructions ever, and those instructions come with the product you purchased. If you can change the oil or spark plugs, you can do the AC work, just follow the instructions step by step.

Determine what you want for your AC system, and email him. He will design a system to do what you need, and give a price for the parts. He includes everything possible. Every screw and zip tie. His products are top quality, and not cheap, but the best parts never are cheap. You will stop on occasion and say, dang, that is clever and wow, that was well thought out.

You can go from just an refresh of the stock system, to full blown 4 condenser, max cool like I did. I drove in 107 degree heat for hours on end, and I was getting hurricane velocity 37 degree air blown all over me, and I was not even the slightest bit warm until I shut off the car and opened the door into 107 degree heat. In Savannah, GA in August, my wife said she was cold, and asked me to turn the temp up. The heat index was 135 that day.

There are endless threads on Pelican about AC. Every possible option is discussed. You can do it all with mix and match parts and invent the wheel and struggle with the project, or spend the money and have Charlie's experience and buy his stuff that just simply works. No guess work.

[911MANN]

Another very happy Griffiths upgrade customer here. I upgraded everything except the fan & knobs (I had recently installed the newer Carrera fan) and the vents (I just wanted it to look original in the cabin). Although I did not do the Mr Ice Project, I did install new Ceramic Window Tinting including windscreen. My 1983 SC keeps me cool enough in Central Florida summers, unless car has been sitting for hours baking in the afternoon sun before I drive. Significantly better cooling than when the car was new, I am quite satisfied, happy even.

[GH85Carrera]

Originally Posted by 911MANN

Another very happy Griffiths upgrade customer here. I upgraded everything except the fan & knobs (I had recently installed the newer Carrera fan) and the vents (I just wanted it to look original in the cabin). Although I did not do the Mr Ice Project, I did install new Ceramic Window Tinting including windscreen. My 1983 SC keeps me cool enough in Central Florida summers, unless car has been sitting for hours baking in the afternoon sun before I drive. Significantly better cooling than when the car was new, I am quite satisfied, happy even.

I visited the space museum in Alamogordo, NM just last month. As always I parked at the far corner of the lot to avoid door dings. I was there for 45 minutes and my car sat in 107 degree heat the entire time. Within 10 minutes I was comfortable. In 30 minutes, I had to turn the fan speed down as I was getting chilled.

[911MANN]

Yeah, Glen, I could have taken my AC upgrades to the Mr Ice Project levels, but I don't drive it as much as you drive yours. And I wanted to keep the system more simple and original if possible- so yes, mine was a happy compromise. If converting to a daily driver or undertaking long summer road trips, it's nice to know I could always add those last few components and perform the maximum Griffith's treatment. Charlie was quite proud of those results (rightly so) when he helped guide my decision.

[grb008]

replaced everything also with griffiths. Upgraded with hurricane fan and my own variable fan control. I have replaced everything stock and is running great.