1985 380sl ac leaking - PeachParts Mercedes-Benz Forum

woodsideraff · #1 10-03-2007, 08:56 PM

I have a leak in my 1985 380SL AC system; The AC looses charge after about 1 week. I took it to my mechanic and he tells me that it would cost about $1500 to replace the compressor and the dryer.

I hesitate to put this much money into the car, even though it's in pristene condition otherwise. The though occurs to me that, since the South Carolina heat is almost over, I could take on the project myself with a lot of time to complete.

First question: What is the best way to check for leaks? I have the system converted to 134A. My initial research indicates that I could purchase a heated diode sniffer for around $200. My mechanic, who I trust, tells me the compressor is leaking. However, other parts of the system may also be at fault in a 22 year old car. Before I undertake the project, I wan't to have some idea about its scope.

Second question: If I were to take on this project, would I be saving much $$?

Any suggestions and commets would be greatly appreciated.

JFawcett · #2 10-09-2007, 05:59 PM

First question...is the compressor leaking or is it the fittings at the compressor.
If it is the compressor, you are out of luck and will have to replace. Whenever you open the AC system you have to replace the expansion valve and receiver/dryer.
IF you want, you can try some of this Epoxy sealant that I used in my car. Called Cryoseal....works great and might buy you some time.....BUT it will not work on compressor or moving parts. $1,500 is not bad......

RickM · #3 10-09-2007, 09:54 PM

Definitely a DYI project. Is it worth it? Depends on what's wrong.

You can utilize a dye that you place in the system and use a blacklight to trace leakage.

If the shaft seal is shot on the compressor you can replace. This may be the source of the leak. It could also be the non-barrier hoses and the use of 134.

The most expensive tool will likely be a vacuum pump to adequately evacuate the system before charge. You can probably rent one though. Autozone loans tools as well. Here's some of what they offer: http://www.autozone.com/in_our_stores/loan_a_tool/air_conditioning/air_conditioning.htm

Here's an excellent site with everything you need for AC: http://www.ackits.com/

woodsideraff · #4 10-10-2007, 09:31 AM

Thanks for the replies.

I will try the dye and black light to try and locate the exact location of the leak. Will also read up on the project and locate the tools needed.

ctaylor738 · #5 10-10-2007, 04:24 PM

It is a miserable job to take the compressor out if you don't have a lift.

woodsideraff · #6 10-10-2007, 06:01 PM

Quote:

Originally Posted by ctaylor738

It is a miserable job to take the compressor out if you don't have a lift.

I don't, but I plan to either use jack stands or purchase a ramp.

ctaylor738 · #7 10-11-2007, 07:45 AM

Then mentally prepare for a tough day.

Also, IIRC you loosen the belt and remove the compressor and bracket as a unit, and then remove the bracket from the compressor on the bench. Installation is vice-versa. Also, aren't some bolts standard, not metric.

Good luck.

woodsideraff · #8 10-15-2007, 06:49 AM

Quote:

Originally Posted by ctaylor738

Then mentally prepare for a tough day.

Also, IIRC you loosen the belt and remove the compressor and bracket as a unit, and then remove the bracket from the compressor on the bench. Installation is vice-versa. Also, aren't some bolts standard, not metric.

Good luck.

Got the service manual this weekend. It's the one with the speedometer on the cover.

I haven't figured out how it's organized. It has many small PDF files with labels that I haven't been able to relate to anything. At any rate, I have located the sections dealing with the compressor.

The instructions for removal call for removing the radiator first. This makes sense to me, and should allow enough clearance to get to the compressor. Would removing also the condenser make sense, or is there enough room to manouver with it in place?

Thanks and regards.