I pulled down the A/C on my 75 the other day and the low side went to 30 real quick. I opened the high side and it would only pull 15 after 30 minutes. I figure I have a hi side leak but where? Texasjack
when ever i try to find a ac leak, i pressurise the system. i made a connector that hooks shop air to the ac lines. then take a squirt bottle full of soapy water (carwash soap works really well because its sudys) and spray down the whole system and look for bubbles.