I never vent R12. I bring R12 cars to my neighborhood AC guy and he does recovery and recharge of R12. For R134 systems I never need to vent because I am either repairing an already emptied system or topping off a system that i've already checked for leaks using manifold gages and thermometer to determine optimal load. If and when i need to empty an R134 system i'll bring it to my neighborhood AC guy.

Dont worry MoneypitSEL i wont help make the perceived or real ozone hole that will allow the suns UV rays to fry us up. You never did answer me, are you power washing off grease and oil with water or something else?

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1972 450SL
1982 300D Turbo