is the any way to find what o ring to put on the pipe if there is not one on it already... i am working on 92 civic with all 134 to the Evaporator ( i think that is what it is called.... the part in the dash) and that is R12

thanks

 

I wouldn't think the "o" rings per type of freon would matter.
Not knowing exactly what type of 92 your working on, or if it makes a difference for that year.

Go here and see the diagram

AC Parts <---- Click Me

Good Luck