Sanden AC Compresser Install Questions

[DonMo]

For those of you that have gone the route of replacing your Nippondenso with a Sanden AC compresser, I have a couple of questions. FYI, I am staying with R12 (or Freeze 12) for the effieciency.

1. What model compreser did you choose, SD 507 or SD 508 ? ( I think the only difference is capacity with 8 being bigger than 7).

2. Did you need a different mounting plate ? (I am going from Nippondenso to Sanden).

My plan is to

1. do a barrier hose replacement where I send the old ones out to be rebuilt for $125 or so
2. add a fenderwell condenser (got a old 12"x12" one in good shape with a fan (still have to decide front or back, I think front is easiest hose wise, but requires relocating windshied washer bottle, back easiest to do but hardest hose wise and still have the exhaust heat as a concern)
3. new compresser (Nippondenso is leaking at seals and they have a bad reputation for rebuilding according to several folks I have talked to). Found a new R12 O ring SD508 for $189 with clutch.

I plan to use the black light leak detection before hand to see if I have other headaches to deal with.

Based on hands on experience, are there any other challanges I need to be aware of?

[88911coupe]

I'll have to go look later since I don't know the model but it came with a special alum. mounting plate that replaced the one on before. I think it was made by the company I got it from...sorry, it was Vertex in my pre Pelican days.
I am also converting to Duracool.

[Jim Sims]

-Install a new receiver/drier (water and R-12 produces an acid which will corrode the system from the inside out).
-If you install an additional condenser it must be upstream of the receiver/drier - this will require additional/different hoses and fittings - not an easy thing to "plan for"- usually requires some trial fitting and routing so sending out the old hoses for barrier hose replacement will be more problematic.
-Most condensers are not robust enough to be mounted in a fender wheel without some type of rock/debris guard.
-Install the additional condenser such that the exit fitting is lowest.
-Use new o-rings at fittings and coat with "Nylog".
-There must be 20 different fitting and back configurations of Sanden compressors in the models you are considering. Be sure and get one that will allow the the hoses to be hooked up and permit access to the charging fittings - it's rather tight in the 911 engine compartment.
- Usually the adapter brackets come as part of a kit with the compressor but you may be able find one separately or fabricate one yourself.
-Be aware that some of the Sanden compressors come with a two groove pulley; this must be removed and the outer lip turned down to avoid interference with the engine hatch which will make a dent from the inside.
-Install the proper amount of oil in the compressor; note that some oil will remain trapped in the OEM condenser if you do not flush it out (highly recommended that you do flush it).
-Do a good evacuation and leak check to avoid leaking out expensive R-12.

Cheers, Jim

[DonMo]

Thanks Jim

I was planning on doing a new dryer and expansion valve (both fairly cheap in ghe grand scheme). The rock guard on the fenderwell condenser will either be a lexan hi strength plastic or lightweight aluminum (same type as they make aluminum doors with for a screened in porch).

You are right on the hoses, that is why I was looking to go to the front driver well, I should be able to move a smaller washer bottle inside the trunk and run hose from the front condenser to the fender. I got the fittings with the condenser, so I was planning on making a rope templete for the hose rebuild.

I wish I could get the exact model for the sd508, these compressers are real popular for retrofitting classic hot rods but I would hate to get a great price for the wrong setup.

[fred cook]

I put a Sanden 507 compressor in my '80 SC about 2 1/2 years ago. This compressor is rated to spin up to 7,000 rpm so it matches my SC engine capabilities very well. It came with an adapter plate that bolted to the original sliding adjustment plate and was simple to install. I pulled the old a/c hoses out and cut the crimps off so that I could reuse the fittings. I bought new barrier hose (by the foot) from my local NAPA dealer and he let me use his hydraulic hose crimping machine to install the old fittings into the new hoses. Total cost to rebuild the hoses was about $150.00 using the best hose available on the market. I also changed the dryer at the time of the rebuild. I decided to go with the R134a coolant because of the much lower price. Even after 30 months, my system still does a pretty good job of cooling the car in our 90-100 degree summer weather!

Remember to close the engine lid when recharging the system or the tech will not get the right charge in the system. The condenser on the engine lid has to have air flowing thru it in order to work properly.

Good Luck!

Fred Cook
'80 911SC coupe

[Hladun]

I put in a 508 from a wreaked SAAB. I'm using R134a and it works fine. I made up some brackets from 4 small pieces of angle iron. I also mounted a pancake fan under the deck lid condenser and that has helped. (Check my previous posts on how I did it.)

[scottb]

I've heard that the difference between the Sanden and Nippondenso compressors is almost inconsequential. The big change is going from a York to Sanden. You might want to do some research on whether you're truly getting any noticeable improvement with the Sanden. Contrary to public perception, like the Nippondenso, the Sanden is a piston compressor. It is not a rotary. You might consider staying with the Nippondenso and avoiding all of the fitment issues. They work just fine when the rest of the system is up to snuff.

A 12x12 condenser is pretty big. Are you sure it will fit? Also, be careful when using a solid rock guard. You might restrict airflow too much. I installed a condenser in my front left fender, and fabricated a rock guard from sprung steel. It provides protection, while at the same time allowing good airflow.

I realize there's a debate over the effectiveness of the ProCooler. I installed one when I added the front condenser. The combination of the ProCooler and extra condenser gives me vent temps in the mid-to-high-30s on hot days. I'm very happy with the improvement.

Good luck, and keep us posted on your project.

Scott