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Any assistance will be appreciated.
1985 745, r134 conversion.
Just repaired leaking hose. System was depressurized for 6months, but was not opened to atmosphere. Hose was replaced, system vacuum out for 30 minutes. Check to ensure vacuum was maintained before filling.
The owners manual says it holds 1300grams of R-12. So I put in 3 cans of R-134 (340g cans = 1020g total).
I anticipate that I lost oil so I added about 1/2 a can.
The air does not blow cold. Compressor works fine. The pressure readings are as follows.
air temp ~ 85 F
Humidity ~75%
Low side Pressure at idle 70 psi @1500 rpm 55-60
High side Pressure 175psi does not vary significantly with RPM.
Why is the pressure so high on the suction side. I am used to seeing a wider spread (i.e., 40 psi and 250) from my GM experience.
Is it possible that I added to much oil? Is there a drain plug for the oil at a low spot (drain some but not lose to much R134)

Did you do the 134a conversion or was it done before the leak occured?

I agree with Jon. You should start over. If you did the conversion then you need to replace the reciever/dryer and the expansion valve.

Plus be sure that both of your fans are in good working order. You will need to pull all the air you can through the condensor.

Make sure the condensor is clean on the outside. The BMW condensor is famous for holding plenty of road dirt!

Make sure that no incoming air can bypass the condensor and go straight to the radiator.

The reason you need synthetic oil is that minerial based oil will not circulate with 134a gas.

How clean is your evaporator?

Good luck.

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