AC Compressor Clutch Replacement?

[inheritthefire]

I recently found out that my AC compressor does not engage when I turn on the AC in my 2000 Firebird.

I already checked the relay (swapped with the horn relay, which is a good relay) and that was functioning properly. I also thought maybe I had run out of freon, causing the low pressure sensor to tell the clutch not to engage, but after jumpering the connector for that sensor, the clutch still did not engage.

I then attempted to put 12v straight to the compressor clutch, in order to get it to engage. I'm not 100% sure I did this correctly, but if I did, the clutch still did not engage. I made some wires and connected each end to the battery, and then touched the wires into the connector on top of the clutch assembly, and nothing happened.

This leads me to believe that I have a bad clutch on the compressor. Is it possible to replace only this part, and if so, how difficult is it to do?

I know I will probably need some special tools, like a pulley puller or something similar...

Any help is appreciated!


***Update: I retried applying 12v to the clutch, and heard it click as it should. I must not have made a sufficient connection previously.
Now I think it must be something other than the clutch, relay, and low pressure sensor. Any ideas?

[landj]

Re: AC Compressor Clutch Replacement?

Have you checked the pressure with the clutch running? If not, I'd give that a try.

[Cool81z28]

Re: AC Compressor Clutch Replacement?

If you don't have a/c guages you could try to add freon to see if the clutch engages then.

[Rob Bell]

Re: AC Compressor Clutch Replacement?

You need at least one gauge on the low side to see if the pressure is there. Also, once the clutch is running, the pipes and accumulator should be cold enough to quickly form condensation. If not, the freon is probably too low.

[inheritthefire]

Re: AC Compressor Clutch Replacement?

Alright, here's another update...

I jumpered some the relay and got the clutch to engage whether or not I had the AC on. When the AC was on, however, it didn't blow cold, or change the air temp at all.

For reference, I jumpered these points:


Now... this makes me think I really do have a low charge of freon, but at the same time, I jumpered the low pressure sensor, which should've bypassed this fact and engaged the clutch... correct?

To make sure I've got the right plug, is this it?


Lastly, if I need to add freon / check the pressure of the charge, is this the correct point for doing so?


Thanks for the help!

Also, on a side note... The fuse panel in the picture of the points for the relay, is there supposed to be a fuse in the top left hand corner? In the picture that tells you what each one is on the cover, it shows that there should be a 15A fuse there, but mine is missing... Should there be one there?

[landj]

Re: AC Compressor Clutch Replacement?

If air temp not changing with the clutch engaged, as Kaylee would say "It's broke captain."

Just what's broke is hard to tell without guage(s). Clutch is turning, so it's likely not the clutch itself. Could be no freon, could be a bad expansion/orifice tube. Either way, you would likely want to replace the orifice tube and drier anyways, so best to figure out what else might be wrong now and whether there any other leaks to worry about.

What's the low side pressure with the compressor turning? I'm no expert and I have a different year, but that looks like the low side to me, usually they are on or near the accumulator.

[inheritthefire]

Re: AC Compressor Clutch Replacement?

I haven't been able to measure the pressures yet, as I don't have gauges, and I've been caught up with work and other things, so I really don't get a ton of time to mess with it.

If I do end up getting a kit with the gauge, I'll post the pressures when I get a chance... if it doesn't happen before Thursday, it won't be done for a couple weeks, as I'll be busy.

[Rob Bell]

Re: AC Compressor Clutch Replacement?

You won't know the pressure until you test it with the gauge. Also, you can try pressing in the pin to let a little freon out. If it comes out really fast, you probably have enough. If it sounds kind of weak, then it probably needs a recharge. But a gauge is really the only way to go. Hissing freon is just a quickie check and of course is not much help unless you know what to listen for.

[ssms5411]

Re: AC Compressor Clutch Replacement?

If the accumulator isn't getting cold then the clutch isn't working , when you turn on the A/C if it doesn't engage then either like said low freon which means you have a leak or the A/C compressor took a dump. Nappa has a kit for like $55 with a gauge and 2-3 cans of freon with stop leak and oil in them , well worth the money. When putting it in make sure the A/C is on MAX and have a temp gauge in the vent should be about 30-40 degrees coming out the middle vent. You can also unplug the A/C and plug it back in to make sure its just not a loose connection and also look at the wires for the A/C to make sure none are loose or dry rotted and grounding out. If its low then of course you'll need to track down the leak. I'm trying to remember what I did to mine but I can't remember right now , maybe later it will come back to me. I know mine usually locks up at the compressor ,so I have to keep the A/C on at all times or the belt will melt becuase the A/C pulley won't turn. I just remembered does your fans come on when you turn your A/C on?