[Daniel R]

No ac , good pressure on r134.
Compressor spins for about 3 seconds.
Used diagnostic but don't know what it means.
92 500 sel
Any ideas?

 

[glenlloyd]

best thing I've found.

K6JRF Auto Page

 

[Daniel R]

Thanks, will dig in to it in the morning.
BTW great bike in your vehicle list
Dan

 

[MikeJT]

No ac , good pressure on r134.
Compressor spins for about 3 seconds.
Used diagnostic but don't know what it means.
92 500 sel
Any ideas?

Have a look at this thread:

http://www.benzworld.org/forums/w140-s-class/1611770-c-problems.html

Mike

 

[limelight]

Check your pressures again.Sounds like the system is low.

 

[Smokiesman]

Dan! It could be a bad pressure switch?

Smokie

 

[Daniel R]

Ok, so how many bar should I be showing at idle ?
I have 20 then shuts off and drops to 10

 

[limelight]

20 is too high. Should be about 7 bar without the engine running and about 12-14 bar with the a/c on.Sounds like the system may be overcharged.

 

[Daniel R]

20 is too high. Should be about 7 bar without the engine running and about 12-14 bar with the a/c on.Sounds like the system may be overcharged.

I tried shedding some pressure, same behaviors.
It acts like a clogged or bad expansion valve/ orifice tube.
Anyone know where it is?:banghead:

 

[MikeJT]

I tried shedding some pressure, same behaviors.
It acts like a clogged or bad expansion valve/ orifice tube.
Anyone know where it is?:banghead:

The a/c clutch may be slipping.

Mike

 

[donkshophorse]

i agree with MikeJT, check for slipping clutch plates on compressor. i had exactly the same as you describe and Mikes old thead on this issue helped considerably, thanks again Mike. sprayed some degreaser between the plates and it made a big difference, still not right but on the way there.

 

[limelight]

Slipping a/c clutch will not cause high system pressures.I think there is a restriction in the system.

 

[MikeJT]

I tried shedding some pressure, same behaviors.
It acts like a clogged or bad expansion valve/ orifice tube.
Anyone know where it is?:banghead:

Are you saying that your pressure with the compressor running is still high?

I don't think 20 bar will cause the controller to stop the compressor running because it's quoted as the pressure to switch the auxiliary fans to max. speed (K6JRF Auto Page).

Mike

 

[Daniel R]

Messed around with it for 2 days, wouldn't work.
My mother in law gets in it today, ac works flawlessly.
Got to do something nice for the car when I get home