I need to get my AC & entire climate better

[junkman300SD]

I bought the 86 with sun roof from a local shop that was supposed to fix the climate control but didn't do a good job. I know that he did vacuum the AC system and refill what he thinks is the proper amount of 134A. The system only drops the temps by 10* so, if it's 90*F outside, I'll see somewhere around 80* out of the vents.

My gauges are MIA so I'll get some more. Is there a 911 specific list of pressures? There are in the FSM for my 00 Dodge Cummins but that came with 134 where the 911 still used R12 so measurements are different.

Next issue: footwell blower motors are shot. What is a good replacement alternative? I want to pay as little Porsche tax as possible but don't want a rigged piece that doesn't really work when I'm done.

3rd issue: The other blowers are likely shot (ie trunk and engine compartment). What are options for repairing/replacing those?

4th issue: heater doesn't heat at all. I suspect something under the car. Perhaps the controls are disconnected or?? I'll look when it's on the lift this week.

[911obgyn]

Lots of info on all these issues in this forum. Do some searching. Footwell blowers are not really neccessary unless you are in arctic conditions. You should hear the servo moving the flapper controls on auto heat controller for heat. AC will not work without clean evaporators, condensers, blowers working.

[Nick Triesch]

I have an 85 911 that I did much ac work on. I bought gauges , pump from harbor freight, I replaced my drier and expansion valve from our host . Bought a rebuilt compressor from eBay and bought a new thermostat and o rings from Kuel . The gauges info tells you how to do a vacuum. If it fails go back and tighten everything back up again . My ac is not great but way better than 10 degrees in a black on black car! Everything costs about $700 when you add in 134. I did mine about 3 years ago I think. I have old hoses so I top off refrigerant once a season.

[junkman300SD]

My children will inherit this car hopefully not until they have to convert to electric because gas is NLA. Which means I'll fix anything necessary.

My next step is in depth research and review to find out what's actually there. I was mostly thinking fans and gas/pressure and hadn't considered dirty cooling surfaces.

[darrin]

junkman300SD -- on the AC front, strongly suggest you read up on Griffiths offerings. Their reliability packages (https://griffiths.com/porsche/air-conditioning/911-930/porsche-911-930-reliability-packages/) provide the parts needed to address the shortfalls/issues inherent in our cars' AC systems via new barrier hoses (eliminating the leaking caused by the porous factory hoses), improved front condenser (additional cooling capacity), evaporator (better extraction/dispersion of cooling air), etc. Due to its middling performance and need for annual maintenance, I'd previously let my factory system sit unused for a decade. I'm now on my third year with the Griffiths system (stuck with stock rear condenser) and couldn't be happier with improvements/reliability I've realized.

[junkman300SD]

I am looking at Griffith. Thanks. I also want to find out how the stock system works as long as it doesn't need expensive parts to get it going. Once significant dollars/effort are required, all options are on the table.

[dw1]

Don't just look at Griffiths, give Charlie Griffiths a call.

He will be more than happy to talk through technical details and various options with you, depending on your budget and objectives. Not only that, he's a genuinely nice guy and an engineer, not a salesman.

Fyi, I replaced all of the hoses on my black/black '87 with Griffiths-supplied barrier type, rebuilt the original compressor using his parts and in-person advice (which was invaluable). More recently, I replaced the expansion valve (which I should have done when I did the hoses - my mistake) and made sure all the fan were running correctly.

The A/C system is otherwise stock. In today's 90 degree weather (NY/NJ area) and very bright sun, I was comfortable driving the car and the vent temps were high 40s to low 50s (deg. F). Not bad at all for a stock system converted to R134a. I did determine today that I could really use a fan speed between #2 (called "medium" but really not much different from low) and #3 (max & very noisy). So I think the Griffiths variable fan speed control is in my future.

Those people who live in more hot & humid areas have found the Griffiths extra condenser and improved evaporator make a 80s 911 a/c system converted to R134a work extremely well.

[junkman300SD]

Will do. I like when things are fixed. I'm driving in tomorrow's cooler 83* heat, 50% humidity down from recent mid 90s without AC. Picking up the truck and moving tools to the shop. Time to get the show on the road.

[Nick Triesch]

Junk man , If you want to see how the original system works you already know from me it’s not that expensive and it was easy!! I have a feeling the pro guys will charge into the thousands.

[GH85Carrera]

Getting the heat, vents, and AC working in a G body 911 is not very complex. No funny vacuum lines or blend doors to mess with. They are three totally separate system. Each or all can are operated with simple controls.

Heat is the easiest. Just the flapper boxed working on the heat exchanges, and you will have heat. The footwell bowers are a little tricky, but there are threads on getting them working. If the blowers run with 12 volts put to them, you are 1/2 way there. Replacing the blowers is not hard, just hard to get. With the heat working right, like mine does, I can;t go more than a mile on a 16 degree day with the heat at max without getting hot. The heater is just overwhelming.

The AC is a very basic system. At best, tuned to 100% perfection, it is pitiful poor performance as delivered from the factory. It works great at night or in the rain, but on a hot day it is just pitiful. Call and talk to Charlie Griffith. He has the solution. It is NOT cheap, but top level amazing quality never is.

I have Charlie's 4 condenser system, with the hurricane blower, and his slick variable speed fan controller and temp controller. The only part left stock on my car is the front and rear condensers. Everything else has been upgraded. I made myself cold on a 100 degree day, driving due west in the afternoon with the sun shining on me, and the dash was so hot I could not keep my hand on it for more than a second. I had to turn the temperature up due to too much cold air.

Read the threads. Do a search for the AC and you will find a hundred or more threads. Same for heater or footwell blower.

Good luck.

[Nick Triesch]

True story on the factory AC. My 85 911 has the world’s smallest front vents!!! What were they thinking?? And a little AC comes out down by my knees and out the tiny window vents. But!! I did make it work! Was fun to get it going. I make it a point not to drive my car in extreme heat. I spent a ton of money on the engine and clutch and other stuff. I’m ok when it cools down for a nice drive .

[junkman300SD]

I want this to be my daily as in start and go whenever there isn't a reason to drive something else. I probably won't get a bike rack for it or drive in the weather unless I run into something while on a trip. Otherwise use it as much as possible.

[famoroso]

If your footwell blowers are shot, the stationary fan cages are likely materially blocking heater airflow.

As mentioned, the footwell blowers aren't really needed, save for perhaps windshield defrosting when you're stationary / at idle.

You can adapt the front condenser fan blower motor for use in the footwell blowers. Admittedly, it's a bit rigged, but it does work. There's a thread here that details the procedure.

All of that being said, I advocate for gutting the footwell blowers, by removing the electric motors and the fan cages, and running them "open."

Here's a shot of disassembled blowers, with motors & cages removed...

[Discseven]

Originally Posted by Nick Triesch

My 85 911 has the world’s smallest front vents!!!

I thought mine did Nick!