AC charging

[RT22]

found some freeze 12 that replaces R12 for my ac how much does the system hold in total? Mine just needs some added but also want to know what it would take to totally fill. I think one or 2 cans should do me. Anyone also ever refill or charge the old r12 system? I know I need gauge set but how hard is it to do? Any tricks or tips?

[Desert Rat]

You sure your '91 is R12?

[RT22]

yes it still has the threaded valves and 134 has the quick connects, all should be on any pre 93 or 94 not sure exactly what yr it changed but by 95 or 96 all had 134 from factory. Easy to tell if the valves are threaded it is 12

[Rev_D21]

The trucks were slow to play catch up. I think by 93 they were R134a. I haven't dealt with an R12 system in about 10 years. I remember needing a hot plate to get the system to take in more r12 from the bottle.

[RT22]

I got a buddy who did my mazda yrs back he is looking in his garage to see if he still has the gauges, he knows how to fill it. My mazda did the same thing as this one was cold while running at cruising speeds but in traffic at idle it was not as cold, he added 2 cans and it was a ice box again. I am just going to let him do it, if he cannot find his gauges I am going to try and find some I can borrow, have a few buds who do house AC and may still have a old set of 12 gauges.

[longtooth]

You add it via the cold side(low pressure) fitting. If you want to fill it to what the spec is you have to evac the system and pull a vac on the system then measure the amount going in by the weight.

That is the correct way to do the system.

The shade tree is at the same fitting but you add untill the a/c compessor dosent cycle very fast but will come and stay on for a good amount of time and the vents are cold.

hope this helps ya out.

[RT22]

yes that helps thanks. I am just wanting to top it back off as it is cold until you are in traffic at idle. then it is only cool. Just need to top it off basically.