Ac Compressor Question

I have a 2000 Grand Prix GTP. I am changing the AC Compressor, because the clutch is squealing loud as hell. I have a used compressor from junk yard. If I change this without a vacuum pump and do not replace freon right away will it cause my new (old) compressor to go bad? I was told if I don't vacuum the system and replace the freon, my compressor would only last for a day or so. Is there truth to this? Thanks for any help provided

The reason a vacuum is pulled on the system is to boil all the moisture from the lines. If this is not done, it will cause your AC system to rust from the inside out. Once you have your compressor on, its probably best to have it vacuumed and recharged asap.

Thanks. I am going to try to borrow a vacuum pump I have been waiting for it, and he has been b.s.ing so I wanted to know if I could just go ahead and do it. Thanks again

You should be fine for a day or two. Just make sure all the freon is evacuated before you open up the system (that doesnt mean just letting it out into the atmosphere).

Also with moisture in the system it will freeze, and possibly cause damage to the compressor.

Just better to pull a good 30 inches of vacuum on it for an hour or so. Hopefully you have no leaks.

Suprizingly my AC works great on my GTP still.

When I was doing refrigeration if possible I would leave the system with the vacuum over night. Then I would start the vacuum pump and open the system to check to see if it lost any vacuum. It is did then there is a leak in the system some where.

It is not leaking right now, just the clutch on my compressor is bad

Does the clutch only squeal with a/c off? It could just be dragging...or does the pulley bearing turn rough when you take the belt off and spin?

If it is the clutch dragging, you can back it off a tad- with the free tool from autozone...

I can remove the belt, pulley spins freely, but it is very noisy. I can turn my A.C. on and it gets quieter when the clutch kicks on. But besides that it works fine. It has been doing this for about a month slowly getting louder and louder

Well then consider my cut and paste...

This sounds like classic v-5 clutch drag- the air gap has tightened (due to corrosion) and needs to be adjusted back to .020" . I have answered this several times- and usually see about 1 a week during the hot season. The noise is a scrapping/rattle only with a/c off- should see signs of metal shavings about the clutch hub. The fix is to borrow the installer/removal tool from autozone and back off the air gap a tad. This can be done on car, without removing compressor or refrigerant, and can even be done without removing the shaft nut since the nut does not bottom on the clutch drive. Pull back the plastic cover in wheel well to access

What would cause the wire to the compressor to lose power? I have a new compressor all switches all fuses are good. If you have any ideas I would appreciate it

Check the pins on the coil terminal- see if they are straight up and not bent. People who unplug the compressor sometimes only unplug one end and then it bends the pins.

Something is telling the relay not to power the compressor. I don't have a clue what works the relay.if anyone has any suggestions I appreciate it

ecm grounds the relay--basedon its inputs-- such as pressure transducer and control head a/c command..