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Garage => Mechanicals => Topic started by: Engineerd3d on 21 May 2021, 07:37 AM

Title: AC Recharge and finally working ac.
Post by: Engineerd3d on 21 May 2021, 07:37 AM
My 300sd with original R12 was low on gas and I was contemplating converting to r134a, after seeing what is involved with doing it properly, new compressor, new condenser, rewire, new tubing. R134 is more leak prone. I decided to kick that can down the road.

With that said i cycled the compressor, and while it is noisy. Its high side was showing a temperature difference. So i figured it was holding some gas. I wanted to charge it. And found some R12 stop leak on eBay, it's labeled as stop leak, but it must include either R12 or R12 like gas in the cans.

I do not have any affiliation with the seller, nor do I make anything from this. But the 3 can package from this seller included a filling tube. I hope it helps someone else here. I am very happy to have working ac on my 300sd.

https://www.ebay.com/itm/R12-R-12-Stop-Leak-Envirosafe-Proseal-Refrigerant-Stopleak-3-cans-hose-/283656884814?_trksid=p2349624.m46890.l49286
Title: Re: AC Recharge and finally working ac.
Post by: raueda1 on 21 May 2021, 09:24 AM
Let us know how it works. You should probably top off with compressor oil as well.  Hard to know exactly how much though unless you evacuate the system and start from scratch.  I did a similar R12 recharge about a year ago.  AC still blowing ice cold after thousands of miles regardless of outside heat.  Good luck!
Title: Re: AC Recharge and finally working ac.
Post by: raueda1 on 21 May 2021, 09:24 AM
Let us know how it works. You should probably top off with compressor oil as well.  Hard to know exactly how much though unless you evacuate the system and start from scratch.  I did a similar R12 recharge about a year ago.  AC still blowing ice cold after thousands of miles regardless of outside heat.  Good luck!
Title: Re: AC Recharge and finally working ac.
Post by: ptashek on 21 May 2021, 10:10 AM
it must include either R12 or R12 like gas in the cans

Highly unlikely. R12 is not flammable, and this can has a flammability warning.

Manufacturer's shop: https://www.es-refrigerants.com/products/w/id/728/t/proseal-for-small-ac-systems-wr1222-hose-kit-9825/details.asp
Here's the MSDS for it: https://www.es-refrigerants.com/docs/30242_37.pdf

Title: Re: AC Recharge and finally working ac.
Post by: rumb on 21 May 2021, 02:53 PM
EnviroSafe is LPG.  I just bought a 35# tank and all the hoses/guages to charge my cars.  I still need to look up exactly how to do it though. 
Title: Re: AC Recharge and finally working ac.
Post by: ptashek on 21 May 2021, 03:48 PM
EnviroSafe is LPG.  I just bought a 35# tank and all the hoses/guages to charge my cars.  I still need to look up exactly how to do it though.

To be honest, the re-gas part is best done by pros with special equipment. The risk of overfilling (either PAG or refrigerant) is quite high.

Prep can be done DIY if the system is empty. Hookup your gauges to the high and low ports, and pull vacuum for a couple hours to boil out any residual moisture. Close gauges, see if the vacuum holds, then re-gas. I've done this on my W124, but the actual re-gas was made by a machine that injected all the right things (PAG, refrigerant, leak detector dye) in the right quantities and sequence based on Daimler issued data. Still blowing cold almost 3 years later.
Title: Re: AC Recharge and finally working ac.
Post by: Engineerd3d on 21 May 2021, 08:12 PM
The lpg part makes sense. For me it was a long shot and it worked so far. Now I'm tracking vacuum leaks in the control system. But the ac part is working fine.

For the evacuation and refill, yes I have done this before. The system was holding some pressure, so this told me it probably does not contain air. So i went ahead and filled it.

As for specialized equipment. Yes and no, i filled 1 can at a time while the system was running. The first can brought the temps down a small amount, the second can did 90% and the third can was only partially emptied in the system as i could see no temp benefits from adding any more. Using a small temp probe showed no more benefits to filling any more. So realistically it was 2.5cans to get me operational.

I will update the thread if anything changes. But for now it's ice cold.