Automotive Air Conditioning Information Forum

I have a1966 Ford with the Name Plate as follows:

FORD No. Y240178 G
PT. C35A-2875-B
R-12 036

I did the "magnet test" and the case seems to be aluminum, but the head bolts are steel. I'm trying to bring the system back to life but it will not hold a vacuum.
I did all the basic tests for finding the leak with no results. I decided to run a can of UV die through the system. The low side pressure went to 90, still nothing visible with the UV light. Today I put the light on the system and there's UV die leaking around the cylinder head gasket area.

My questions are- what brand is this compressor with regard to obtaining a replacement Head Gasket ( I have not seen anything for Ford) and can I do this repair with the compressor still mounted in the engine bay?

One more question, did the pressure go to 90 possibly because of a blocked condenser and/or R/D? Yes, I have a new condenser and R/D standing by to be installed. Thanks, looking forward to any additional tips or suggestions.

I don’t see much sense in trying to overhaul that comp. See if Tim the site owner can suggest a replacement. If he can be a sport and buy it from him, his prices and quality can’t be beat

I believe the OE compressor in your car is a York twin-cylinder type. Parts might still be available if you'd like to keep the system original. Otherwise, I suggest replacing it, as already mentioned.

The low-side pressure suddenly going to 90 PSI is concerning. A sufficient amount of UV dye for this system is about 1/2 of a fluid ounce. Did you put in much more than that? If so, that could have caused the low pressure to spike.

When measuring the pressures, did you ensure to have both valves on the compressor back-seated?

Is this car still R-12, or has it been converted to R-134a?

Thanks for the reply. Yes I had the rotolocks set correctly and it is/was a R12 system. I believe the dye charge problem is on me that I added to much after not seeing any results. Anyway, I know head gaskets are available and I may take crack at replacing it just for the experience. I probably end up replace the compressor in the long run.

Be sure to check carefully for any cracks in the aluminum cylinder head and crankcase castings. If you find any, I'm afraid you'll have to replace the compressor.

Are you planning to keep it R-12?

Make sure that you replace both gaskets. There is a valve place sandwiched between the compressor head and the compressor body. The gasket set should come with both.