Home A/C repair

[Steve N]

Got a DIY question for the group.

1993 525i Touring. The air blows cold and everything works fine when it is charged. Problem is, it leaks. I used a dye and found that it is leaking at the compressor where the high and low pressure hoses attach.

Looking at the parts diagram I see a small O ring in both spots. Keeping in mind that this is a 200k mile car, can I just unscrew the 2 hoses put in the new O rings, recharge and go? What potential damage can I do? Anyone know what size allen head is needed?

-Steve

[Jon K]

Thats about all you have to do - you will lose a ton of refrigerant however. I think its a 6mm, maybe 7mm... i took mine off a couple weeks ago. If you want new hoses that do not leak let me know I have them all.

[Rus]

Generally its best to let a shop remove the refrigerant from the system before you open it up. When you complete the repair, its recommended that you put the system under vacuum to remove any air, moisture, and contaminants that may be in the lines. Then you can charge it with refrigerant. Hope this helps.

[Tiger]

Ditto... you need to vacuum the system before refilling with refrigerant. You probably have R-134a already. You do need to evacuate system before taking that hose off. And yes, just the oring will do.

There is one other thing... try tightening it up more to see if it holds. Then you don't have to do the whole deal.

[Blitzkrieg Bob]

This will help ensure a clean and dry system

[rps1072]

If you open it, it will be relatively messy, but tolerable.
You might be able to find a shop that will let you supply your own refrigerant and only charge labor to vacuum and charge the system. I did this and they only charged me an hour of labor.

[rps1072]

Oh, and Bob's right about the drier--cheap part that should be replaced every time you open that system up.

[genphreak]

Oh, and Bob's right about the drier--cheap part that should be replaced every time you open that system up.

Venting is bad- besides never open it without changing the dryer and never allow the drier to remain open to the atmosphere for long- it should be unsealed only immediately before fitting her in to the system. Do not open the system and then expect it to last if you let atmosphere or dirt enter and use it.

I'd tighten the connections 1mm or so (to move the thread) and take them up a bit to say what feels like around 50 ft/lbs, then clean and check for leaks a a day or two of use after that.

If you end up going into the shop, take a drier (new driers are $20 on eBay); most shops only charge for their time and the refridgerant they use... nick

[BigKriss]

what is a drier?

[Jon K]

pulls moisture out of the compressed gases