69 gmc a.c.

[rdrnation]

I have a 69 gmc with factory a.c., everything appears to be there. I have not tried to charge it. What steps and in what order should i try to get it going? should i buy some freon and just try to charge it and see if it works and go from there? thanks

[TBONE1964]

The first thing I would do is take it and have a vacuum put on the system. If the system will not hold a vacuum then it has a leak.

If it has a leak then you will need to find it. The best way is with dye. If you don't have the tools or equipment it would be best to take it to a reputable shop that can service it.

[Eddie H.]

First, put some gauges on it and see if it has anything in the system.
If it does, turn it on and see if you can get the compressor clutch to engage.
If there is no pressure in the system, hook up an a/c vacuum pump, pull it down to 28 inches and and see if it will hold vacuum. If not, then you need to start tracking down the source of the leak before wasting expensive R12.

[rdrnation]

ok i will do that, thanks

[Ol Blue K20]

Originally Posted by Eddie H.

First, put some gauges on it and see if it has anything in the system.
If it does, turn it on and see if you can get the compressor clutch to engage.
If there is no pressure in the system, hook up an a/c vacuum pump, pull it down to 28 inches and and see if it will hold vacuum. If not, then you need to start tracking down the source of the leak before wasting expensive R12.

It may not pull down to 28 inches if there is a leak

[Eddie H.]

Originally Posted by Ol Blue K20

It may not pull down to 28 inches if there is a leak

Yep, that's right, if the leak is big enough, the vacuum pump can't pull it down that far, but the larger the leak, the easier they are to find.

[Ol Blue K20]

Originally Posted by Eddie H.

Yep, that's right, if the leak is big enough, the vacuum pump can't pull it down that far, but the larger the leak, the easier they are to find.

True very true...