Since it's so hard to find a shop willing to simply recharge my r12 system. Most say all they can do is convert the entire system to R134 but want to charge an arm and a leg.

I purchased the conversion kit from the auto parts store but it didn't work. The fitting in the kit was wrong or something, the kit said r12 to r134. What am I doing wrong?

Basically my question is how do I convert the low and High side fitting to r134?



Thanks

Your car should already be 134a

__________________
1999 C280

What country are you in?

that is what I was thinking.

__________________
Jim

It is ................................

Read the yellow A/C " Refrigerant Type/Capacity Warning Notice " tag on the radiator cross member.

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A Dalton

All MB's starting in 1994 had R134a from the factory!

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really so why cant I get this r134 recharge kit to fit. I got one with a gauge on it from Advanced but it doesn't fit on the low side.

The one with the black cap right behind the compressor right?

I am not familiar with the C class but my 95 E320 has the low pressure side fitting up near the intake manifold and about halfway back to the firewall. The high side is slightly to the front of the compressor and down lower in the engine bay.
You need to find the low side fitting (it is the smaller diameter of the two).
Please be careful and wear safety glasses. This is a job that is better left to someone that understands a/c systems.

Yep... in fact, I think most car companies switched to R134a in 1994. Lexus changed over in 1993.

On my car the other fitting is just behind the grille on the drivers side by the side of the radiator. Open the hood, look at the front of the radiator (where the bugs are) and look at the drivers side of it. See if there is a black cap peeking out. I don't know if that's high or low but the other fitting is behind the compressor. Don't know if it's the same for '95.

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Yep You are exactly correct. Me and a mechanic were looking for about 10min then finally found it. What a weird place, I would have never guessed that location.

The shop couldn't do the recharge because of some other problem with my coolant level, shop policy.
Anyways I fixed the problem with the coolant at home and decided to go ahead and recharge it. Now that I've located the low side yet again the fitting is to big.

Whats the deal? If this is truly a R134 AC car why doesn't the R134 recharge kit fit.

This is crazy, now I have to go back to the shop and let him figure it out.
I would love to know why Mercedes decided to make their fittings a different size other than the common R134 size.

The vehicle fittings are the correct size.

A common issue is with the recharge kits that are disposable = they get sloppy with their production tolerance = couplings fail to fit, or work only with great difficulty.


Question:
WHY do you think it has a low charge?








Have a great day.

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In the E class chassis, the switch over to r134a started in 1992 with the 400E and 500E.

The 300E and 300E 2.8 came with it in 1993.

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you get small size to large size adaptors and vice versa , you can use any of the charge points depending on whether you are using vapour or liquid if you havent done HVAC dont do it yourself you can destroy your compressor vanes , if r12 your system must be flushed and new orings fitted the gasses are not compatible and make an acidic mix which will destroy your system over time , that is why it costs to convert.

just to add to it 134 is also put in by weight not pressure , and I pump it in using a gas pump , and electronic scale on the machine , each system has specific weights , also the compressor must be flushed clean of r12 oil and refilled with 134 airless oil some compressors can be drained easily others must be removed to be drained.Its a big labour intensive job .