You can just add more with one of the adapter kits sold at all McParts. It will have a low side fitting and a can tap (and they even sell a large can with attached fitting for one-shot use).
Hook up to the low side with the compressor running and freon will slowly migrate from the can to the system since it's boiling out of the can. I use a bucket of warm water (NOT really hot water!) to speed things up. Keep the can upright, a slug of liquid into the compressor can be very bad for it. However, if you have a leak and need to do this more than say every couple years, you need to have the R134A recovered by someone, repair the leak(s), properly evacuate, and fully recharge. I'm not a big fan of a simple vacuum and recharge, you really need to find and fix the leaks. Otherwise, air and water are continually leaking in, and this will eventually eat a compressor and/or corrode out the condenser. To properly evacuate, you must run 30" mercury for at least 30 minutes, it's better to run for an hour, to remove the water. It has to vaporize and then diffuse to the pump, so it takes a while. 29" is really too low, it will take forever get the system dry, and anything less you really are wasting your time, the water won't come out of the dessicant or PAG oil. I have a used Edwards oil bath rotary pump that's great, except that it will overpower a small leak and you can't tell other than it clicks once in a while as a bubble of air comes out of the oil. A smaller pump will never reach full vac if you have a leak. Peter -----Original Message----- >From: R A Bennell <[EMAIL PROTECTED]> >Sent: Jul 23, 2008 2:40 PM >To: Mercedes Discussion List <mercedes@okiebenz.com> >Subject: Re: [MBZ] R134 > >I agree with a later post responding. You should likely have the vacuum pump >hooked up for a while. We tried to do >my old MB and the pressure is too high for it to suck the gas in. We just >wasted a couple of the small cans trying. >My brother in law can bring the vacuum pump from his work but we have not done >it again yet. > >Randy > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] Behalf Of Glenn Brown >Sent: Wednesday, July 23, 2008 10:52 AM >To: mercedes@okiebenz.com >Subject: [MBZ] R134 > > >>From what I experienced on a recent trip, I believe I need my R134a topped >up. Since I've never done this, is there anyone who can provide 1) Whether >or not I can do this myself?, and 2) The specifics? >TIA. > >G. M. Brown >Brevard, NC >_______________________________________ >http://www.okiebenz.com >For new parts see official list sponsor: http://www.buymbparts.com/ >For used parts email [EMAIL PROTECTED] > >To Unsubscribe or change delivery options go to: >http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > >_______________________________________ >http://www.okiebenz.com >For new parts see official list sponsor: http://www.buymbparts.com/ >For used parts email [EMAIL PROTECTED] > >To Unsubscribe or change delivery options go to: >http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
