Hi everyone,

I bought my 240D from the original owner (though he leased it to someone for a while while he was overseas). He told me that he had not done a r134a conversion, and there was no sticker obvious inside the hood - so I thought it was still running on the original freon.

BUT, I was under the car last night chasing down oil leaks, and I wiped off a label on the compressor - it said it contained pressurized r134a.

Also, the cooling is there, but weak when the outside temp is above 90F.

All this seems to indicate that the retro fit was done. Maybe by the leaseee, who also replaced the original radio while he had it

What do you think? How can I tell if there is no sticker under the hood?

__________________

Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

You should be able to tell by the fittings on the hoses. If they are screw-on, then it should be R12. If they are snap-on, then it should be R134a. And then there are all the blends.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References

Thanks!

I will check when I get back out to my car....what if they are screw on?

Does the compressor or the fittings take precedence - I mean do I recharge with r134a or R-12?

__________________

Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

Hard to say...

You won't be recharging R-12 easily, that's for sure, you can't buy it anymore/without a license anyway.

R-134a is available at most auto parts stores.

If the fittings are screw-on but the compressor says R-134A, stop and take it to an A/C shop right away. Otherwise you risk either destroying your A/C system by an improper fill, or releasing terrible chemicals into the atmosphere.

__________________
1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

The only way to do better than what you have is to go back to r12. You can install a parallel flow condenser and keep 134 with good results too.

__________________
Jim

Neither of those items means anything. Compressors don't come charged with refrigerant; the label could say R-134 and the system could have been charged with R-12 (along with other possibilities.) Hose fittings may or may not have been changed if the system was modified.

Seeing how changing the hose fittings is one of the legal requirements to retrofit an R-12 system to R-134A, if someone did do the conversion but didn't change the fittings, they did it very wrong.

The fittings are different so you can tell at a glance what's inside.

__________________
1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

That's a very good point, jk. I totally overlooked the fact that things are always done correctly!!! Sometimes I confuse reality with theory.

well, the fittings look like they screw on, in fact, they look original. The brass is patina-ed with a dull finish, the insulation cuff over the tube that goes across the front of the engine is completely dry-rotted and there us a good deal of road-grime patina around each connection - it has been a very very long time since they were touched by a tool. Even the red and blue caps on the ports look pretty much untouched.

The compressor also looks like it has been in for a while - not original, but pretty "settled-in" so it has been in this state for quite a while - any conversion was a while ago.

The thing is - it does work (weakly in the heat, but a little bit is better than nada) - so I don't want to go changing anything just yet (got other things to fix first)- just wondering what happens if (when) I need a charge - and whether I can do it with cans from the auto store or if professional help is needed.

I have read some pretty heated discussions here about "contaminating the R-12 supply" with r134a...

Thanks for the input so far!

__________________

Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

IF the compressor had been replaced with a new unit, the label on it might read "Caution R-134a under pressure" or something to that effect. It doesn't necessarily mean the system is charged with R-134a. It's just a standard warning label. The same compressor can be used with R-12. This style compressor was used by GM into the R-134a era, so they can be labeled this way. There's a small chance that someone put R-134a in the system and did not change the fittings; but it's really not likely because the quick connect 134a fitting is necessary to connect even a simple 134a charging hose. Most likely you have good old R-12, and maybe it's a bit low on charge. My 240D has R-12 in it and still doesn't perform all that well in hot weather. Maybe I'll have to replace the expansion valve and drier and start over again. That's a winter project, though...

__________________
Erich Loepke
2010 Ford Focus
Currently Benz-less

[/quote]Most likely you have good old R-12, and maybe it's a bit low on charge. [/quote]


That sounds like where I am at considering the the state of the tubing.
thanks!

I think I will start hunting for a local shop with R-12.

Or maybe I will take that certification course someone pointed to on another thread.

__________________

Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT