A/C Project on an '84

[Hoppe]

Background: I purchased my first 911 in April of last year from a Pelican in Ohio. The a/c worked like he said but that was in Ohio and not NC. July and August proved I needed to do something if I wanted to drive my new prize in more than mild weather.

The car: 1984 Targa in slate blue metallic. 135k miles on it when I picked it up. The car was previously converted to R134a. The evaporator had also been upgraded to the Kuehl Serpentine and the Kuehl Wirbelsturm Evaporator Blower. The system did really blow....literally, just not cold enough.

Solution: Based on reading threads and asking questions, I decided the quickest solution to my problem was adding a fender condenser. Eventually, I will replace the barrier hoses, and possibly replace the front condenser with the Kuehl version from Griffiths. Since I just purchased the car I needed to control the cost.

I decided to purchase the fender condenser from Zim's. The price was good ($500) and the product seemed to get good reviews.

Here is the kit that arrived:

The kit was well packaged and included the following: Condenser, fan, wiring, relay, hose fittings, hose, mounting brackets, hardware and detailed instructions.

Here is a closer look at the condenser and the puller fan that comes attached:

The kit arrived last September. The weather got cool and it got put on the shelf in the garage. April and May came and the top came off. June hit and I realized the top can't stay off forever. So I decided to attack my first big auto project outside of replacing the radio and changing some fluids. I am handy but far from an expert when it comes to autos. I will post follow ups of my install experience, the good, the bad and the screw ups. Short story---I am pleased with the results.

[Hoppe]

After reading the instructions a few times I took a day and disconnected from the condenser the hose that runs from the condenser and up the left side of the car. I also removed the hose from the mounting brackets underneath the car, from about the front of the wheel well and back. I then used a jigsaw to cut the hose under the car close to the point the hose entered the engine compartment. You kind of realize you are at the point of no return when you pull out the cut hose.

The hose that is shipped with the new condenser comes with a flare fitting and an o-ring fitting. You cut off the end with the fitting you do not need.
and route the new hose from the engine compartment to the bottom of the car. It is a tight fit and the instructions recommended lubricating the hose with wd-40 so it would slide through a little easier.

End of the old hose coming from the front and the end of the new hose coming from the end engine compartment.

After this I disconnected the hose from the receiver/drier and removed the old unit and mounted the new one. Done for the day. About 4 hours for a newbie. I then ordered my manifold set, vacuum pump and flush kit on Amazon and picked up some flush solvent at O'Reilys.

[Discseven]

Hoppe... Are you crimping on fittings after determining hose length?

[GH85Carrera]

Originally Posted by Discseven

Hoppe... Are you crimping on fittings after determining hose length?

Yea, regular hose clamps will not work. They need to be crimped on or you will likely have leaks.

[Hoppe]

Originally Posted by Discseven

Hoppe... Are you crimping on fittings after determining hose length?

No crimping. I used the fittings and hose clips provided. The fittings were extremely tight going into the hoses and I go the hose clips as tight as possible. So far, no leaks from those connections. Crossing my fingers.

[uwanna]

Originally Posted by Hoppe

No crimping. I used the fittings and hose clips provided. The fittings were extremely tight going into the hoses and I go the hose clips as tight as possible. So far, no leaks from those connections. Crossing my fingers.

Yes, there are hose clamps made specifically for AC hoses. I have used them several times. The clamps are very heavy duty, stainless steel and have a little "tang" welded to them at a right angle to space them correctly from the end of the cut hose and to place them correctly over the barbs on the fitting. They do work when installed correctly. If this is the type of clamps supplied with your kit, they should be just fine for your install.

[uwanna]

Originally Posted by GH85Carrera

Yea, regular hose clamps will not work. They need to be crimped on or you will likely have leaks.

These are the special hose clamps designed for AC hose barbed fittings. Have used them several times with no leaks.

[Hoppe]

Day 2 - Rent a compressor from Home Depot to use in flushing the system, buy a can tap for the refrigerant, and then picked up some more flush solvent after I realize one quart would probably only do half the job. Get home and get the compressor set up and flush kit filled. Then realize the flush kit does not include an adapter to connect to the compressor hose (did I mention I am a newbie?). Back to HD for an $2 adapter. Here is the completed flush gun..

Instructions call to flush the old hose from the new condenser forward and flush the new hose back through the original condenser (the compressor was removed the night before and is draining upside down at this point). The flush forward worked perfectly. I used a funnel to route the output to a bucket sitting in the front left wheel well (it comes out of the hose that is not yet connected to the receiver/dryer). The tip of the flush gun could have been smaller/pointer to actually fit down in the hose but I applied enough pressure to hold it in place and push the flush through. After the can was empty I continued pump air through the hose for several minutes to help dry out the system.

The flush to the back did not go so smoothly. Always make sure your hoses are connected as instructed. I had not connected the new hose securely to the old condenser. Flush everywhere. And it stinks. Luckily it evaporates fairly quickly. The garage only smelled for a couple days. After I connected the hose I started again. I was using a remnant of the cut hose to drain the old condenser to a bucket. When the air pressure hit the hose, it popped out of the bucket. More flush all over the garage floor. Nice. Amateur.

Between the back and forth to HD and the trip to the LAPS and the screw up with the one flush, I finished 3 hours into a 4 hour rental. Experience would have put me at half that.

[Hoppe]

Originally Posted by uwanna

These are the special hose clamps designed for AC hose barbed fittings. Have used them several times with no leaks.

Those are the clamps I used, unfortunately I put them in backwards. However, it does appear that I put them in the right distance from the end.

[Hoppe]

Afternoon Day 2 - Hooked the hoses to the new receiver/dryer, which took longer than it should as it was out of position slightly. Then put the new condenser in place with the new fittings loosely attached in order to finish cutting the old and new hose to the proper length. After the hoses were cut I inserted the fittings. They were very tight so I lubed them with PAG oil to get them fully inserted. I waited to tighten the hose clamps until they were connected to the condenser.

It took a while to attach the hoses to the condenser. I kept playing with them to get the right angle on the hoses so as not to interfere with future jack stand placement. I had one scary moment when I raised the left side of the car to get the jack stand out of the way. The right rear came of the stand. Luckly it caught something in the wheel well and I had time to correct.

After I was satisfied with the positioning, I mounted the condenser. Three self-tapping screws are provided but you only need two. It took a little pressure and a fresh battery in my drill but I got them to seat. Its a good firm fit. The condenser fits in snug in the back so you only attach it on the front. Following is the mounted condenser and a shot of the hose fittings:

[Hoppe]

I put PAG oil in the drained compressor as instructed and reattached it. I ran the wires from the fan relay to the fan, to the compressor and the open third fuse in the engine compartment. To get the wire to the fan, I got under the car and put a straightened clothes hanger up through the hole that the hose went through and then I crimped it around the wire and pulled it through. That wire could have been a foot longer to help in routing it to the fan's power line and keeping out of the way of the tire.

The wire to the compressor must tap into the compressor harness. A self tapping connector is supplied. I found it to be two small for the existing compressor wire. It would not close and lock properly so I had to wrap it in electrical tap. All in all the instructions were pretty clear regarding all the connections and the electrical was the part the scared me most.

[blucille]

Hate to burst your bubble....shame about those clamps....i'd be afraid of the tab working its way into the hose over time....the easy fix would be to snip off the locating tab on the clamp, if you are feeling lucky, you could try unscrewing the clamp all the way and locating it properly.

[green_chile]

Thanks for posting your journey including the little mistakes. I will most likely be doing this myself.

[Hoppe]

Originally Posted by sonett43

Hate to burst your bubble....shame about those clamps....i'd be afraid of the tab working its way into the hose over time....the easy fix would be to snip off the locating tab on the clamp, if you are feeling lucky, you could try unscrewing the clamp all the way and locating it properly.

LOL. I don' t feel lucky. Thanks for the advice, I will clip the tabs.

[Hoppe]

Day 3 - Vacuum and charge. I pulled a vacuum for 30 minutes but I really did not pull a vacuum. I tried. Make sure all your fittings are tight, at the vacuum and at the manifold. Also, my pump had two fittings and the unused fitting was not completely tight. I was sucking outside air. Once I got it all tightened up the pump got quieter and I was able to pull the vacuum. The vacuum held and I continued to pull the vacuum for three hours as recommended by Griffith's.

Time to charge. I got the wife to hold the car to 2000 rpm as recommended. I opened up the can and opened the low side. Refrigerant started to load. All seemed good.

Now notice the high side hose position in the photo............not good.


Half way through the first can this happened:



A little oil came out and some refrigerant. I probably discounted how much.

I turned off the car, closed the low side to stop the refrigerant and disconnected the high side. Started the charge again and finished putting 24 oz's in as recommended.
I was probably focused on too much on oz's and not enough on the pressure.

[Hoppe]

After the charge I drove the car and my infrared thermometer showed 32 at the vent. Ambient temp was approx. 80 and the car had been sitting in the garage. I was a happy man The next day I drove the car to work. Still in the low 80's but my temp was 42. It looked like I might have a leak (separate post on that).

Luckily I had used R134 with a dye in it. I blacklighted the car that night and there appeared to be a leak at the connection of the new hose and the old deck lid condenser as it lit up under the black light. I wiped the connection down and then blacklighted the car the next few days, focusing on the connections touched. No leaks appreared, even at the spot of the previous leak. I guess it sealed up.

I came back to the car on a mid-70s day and put the gauge set on. I was below 20 on the low side. I figure the "temporary" leak did it or the cut through the high side hose. I added another half can and got the system to 25lbs. Still checking for leaks a week later but so far so good. On a 83 degree and cloudy day I got the following with an instant read thermometer after driving 15 minutes at 75mph:

The infrared showed this when the laser was on the back of the vent.

Not sure why the big disparity but I believe the instant read is more accurate since it is getting the airflow inside the vent. I got approx. 43.3 degrees yesterday when ambient was 89 and sunny. It took me about 25 minutes for driving to get there.

[Hoppe]

Summary: All in all I am happy with the project. What took 2 1/2 day should have probably taken a day and a half, which is typical of most projects I do since I usually don't have all the equipment I need and I am doing it for the first time. The cost was approx. $725, which included $500 for the condenser, the vacuum pump and manifold set, R134a, flush kit, flush solvent, compressor rental and a new high side hose.

The condenser and mounting kit were of good quality and the instructions were good. The wire to the fan could have been a little longer, the self tapping wire connector a little bigger. The instructions do assume a certain level of knowledge. They could have explained where all the O-rings were to be used and identified all the little parts in the kit but that is from the view of a novice. Someone with experience would have no issues.

I am happy with the results. I did not charge it perfectly and could probably get it a little colder if I evacuated and did it again. I had my little cut hose issue and I know now I did not bleed the lines so there is probably some air in the system. That said the car does get to 72 degrees inside and I am comfortable. It would be nice if it got there a little quicker.

Future plans - I will replace the hoses in the next year or so. I will probably also change out the front condenser. I also need to evaluate the front condenser fan as it does not appear to blow much air over it. Short term I may try to add a fan to the deck lid condenser. I appears that is debated but I figure the it may be worth a try given the limited cost.

Thanks for reading. I hope this helps someone else in the future.