AC compressor oil amount

myfirstls

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Aloha guys.

yesterday, I manage to remove my AC compressor (what a chore! it removes pretty easy, but you have to wiggle it around to get it out!) and as the manual states, I turn the clutch itself to get the oil out so I can put back the same amount it came out.

Now, my new compressor is from 4 Season and it said it has 3oz of oil already in the compressor. What I remove from the old compressor looks to be way less then that 3 oz. More like 2oz, at the most. I do have cylinder that measure oil amount (I ride and maintain motorcycle as well) so I will get accurate measurement later (I'm on my lunch break now).

Should I add little more oil in there or should I just bolt up the new compressor since the oil from old compressor had little less oil in it?
 
I'd bet you leaked most of your oil out.
Why are you replacing the compressor?
 
Thanks Joe. I didn't drip any oil when I took out the old compressor. You suggesting I may have a leak somewhere?

I'm replacing it because my AC fuse (#1) kept blowing. I did replace DCCV because I had #2799 but it still blew fuses. I unplug the DCCV and it still blew.

Finished with compressor install, recharge the system and so far, fuse hasn't blow yet and ice cold AC. I did add little more to the compressor (around 2oz) before sealing the system.
 
Keep the old compressor then. It just needs a new clutch. When I tried an aftermarket compressor, it only lasted about two months.
 
Keep the old compressor then. It just needs a new clutch. When I tried an aftermarket compressor, it only lasted about two months.

What would be the main issues with aftermarket compressors outside of the generalization of lesser quality? In your particular case was it the valves, switches, clutch? Did you replace the expansion valve as well per service manual?

Not to be confrontational, I’m just curious. I replaced my original compressor once a few years ago and it ended up going out after a few month like you, but I only did the condenser and compressor. This past summer I posted in the dash removal thread about my overhaul. I did it all except pressure lines - Expansion valve, condenser, drier and compressor.

The compressor was same as OP (Four Seasons). I verified the oil amounts in all components, torqued fittings, vacuumed and filled to OE specification and have been issue free with the exception that I suspect a leak at the low side valve. But everything was good all summer and fall.
 
Not to high jack the thread, but can you have A/C serviced properly during winter months? I’d like to find my leak with dye, but that usually requires running the system for a few weeks then checking with black light.

I want to use the A/C with the heat as designed, but I need to solve the leak and refill first, but can you fill the system properly with ambient temps at 30-40 degrees F.
 
Thanks Joe. I didn't drip any oil when I took out the old compressor. You suggesting I may have a leak somewhere?

I'm replacing it because my AC fuse (#1) kept blowing. I did replace DCCV because I had #2799 but it still blew fuses. I unplug the DCCV and it still blew.

Finished with compressor install, recharge the system and so far, fuse hasn't blow yet and ice cold AC. I did add little more to the compressor (around 2oz) before sealing the system.

Did you replace the drier as well? I think that figures in .75 oz that you add directly to the drier. There is a thread on A/C oil amounts and I think you’re fine with what you did. However, you’re supposed to verify the new compressor oil amount and not take the manuf. word for it.

Worst case, if you have too much oil it just effects your cooling capacity vs. too little oil that will ruin your compressor.
 
What would be the main issues with aftermarket compressors outside of the generalization of lesser quality? In your particular case was it the valves, switches, clutch? Did you replace the expansion valve as well per service manual?...

It was either the scroll control valve, or the clearance of the scroll plate.
I replaced the dryer (always do that after opening a system). I did not replace the expansion valve. That looks like a two day job to get the whole dash out and back in. What are the odds that some of the plastic wouldn't break in the process?
There was no contamination anyway. The OEM compressors that I put in each of my LSes are still going strong, and it's been a while now.

Not to high jack the thread, but can you have A/C serviced properly during winter months? I’d like to find my leak with dye, but that usually requires running the system for a few weeks then checking with black light.

I want to use the A/C with the heat as designed, but I need to solve the leak and refill first, but can you fill the system properly with ambient temps at 30-40 degrees F.

It's harder to correctly charge the system when it is cold out. You can't go by pressures when its 60 and below. You can still do it by weight, but you have to completely discharge and evacuate it to do that. Most places have a machine to do all this automatically.

Check the bottom of the compressor and all the line and hose connections. It should be oily/dirty where the leak is. The factory put green leak dye in.
 
Keep the old compressor then. It just needs a new clutch. When I tried an aftermarket compressor, it only lasted about two months.

Yes Joe. That's my plan. Still have the old compressor and planning to service it ASAP. I don't trust aftermarket and because of where I live, need the AC all year long.

BTW, what type of clutch do you recommend? OEM or aftermarket?

Did you replace the drier as well? Worst case, if you have too much oil it just effects your cooling capacity vs. too little oil that will ruin your compressor.

No. Only thing I replace was the compressor. As I mentioned above, I needed my AC ASAP. For about month, I did not have my AC and I was dying for it. Yeah, I figure little too much is better than too little.

In any case, thanks guys.
 
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You should always, always replace the dryer. It's pretty cheap anyway.
I don't have a good recommendation on the clutch. I'm not too fond of the OEM clutch design.
 
You should always, always replace the dryer. It's pretty cheap anyway.
I don't have a good recommendation on the clutch. I'm not too fond of the OEM clutch design.

Thanks Joe. Yeah, I know some component(s) should/need to be replace, but I/we need AC ASAP here. We are in mid to upper 80's here right now.

Anyway, I plan to replace most of the components next time compressor fails. I'm collecting parts right now. Why? I attached the gauge when I was recharging and I don't like the pressure. As of now, still searching what seems to be the problem, but at least the AC is working, ice cold. So in the mean time, collecting parts for my next AC project, including replacing the clutch but that can be done soon as I have old compressor tucked away.
 
Which pressure(s) didn't look right? If the high side was too high, it could be a saturated dryer, or a dirty condenser, or a fan issue.
Surging pressure would be a saturated dryer with moisture freezing at the expansion valve.
 
Which pressure(s) didn't look right? If the high side was too high, it could be a saturated dryer, or a dirty condenser, or a fan issue.
Surging pressure would be a saturated dryer with moisture freezing at the expansion valve.

Thanks Joe. Condenser is nice and clean, at least from what I see from outside and I can hear the fan at different speed. Also, I don't see anything freeze up (of course, I can't check the expansion valve at the moment), but engine compartment is warm (hot) anyways.

According to the manual, I supposed to have somewhere between 35psi to 60 psi @ 85 degrees but I only have 30 at best on the low side, and high side climb up to more than 200 before clutch start cycling and brings it down to 150 or so.

But for now, AC is ice cold so not too worry about it, until something fails next time. And I hope by then, I have all the parts I need. It was in very humid for us today and was in upper 80's.....................
 
It's not a cycling clutch system. It won't disengage the clutch before the pressure gets to somewhere around 400 (or less than 50 or so) due to pressure. (Really, it should never inhibit due to pressure unless it is very very cold.) You are seeing the clutch disengage due to the evaporator temperature getting too close to freezing, due to the low low-side pressure.
Did you have the blower on maximum, system on fresh air, and the windows open?
 
It's not a cycling clutch system. It won't disengage the clutch before the pressure gets to somewhere around 400 (or less than 50 or so) due to pressure. (Really, it should never inhibit due to pressure unless it is very very cold.) You are seeing the clutch disengage due to the evaporator temperature getting too close to freezing, due to the low low-side pressure.
Did you have the blower on maximum, system on fresh air, and the windows open?

Thanks for reply Joe. Yes, I did it according to the manual. Lowest setting on AC, dual function disable, blower max, fresh air and both side front/rear windows wide open. However, I did not open the rear doors (I forgot to open while in test). It goes up to around 200 (maybe little over 200) and goes down to around 150. Low side is steady at around 30 (give and take 2-3 psi).

But as of now, I'm not complaining because I have ice cold AC. Better than before. So I am in search of the components right now. I just bought aftermarket coil for compressor from Autozone. Looking for drier right now. Nothing is wrong with expansion valve right now, but I like to have that just in case something goes wrong. Also planning to get another DCCV just in case because my Motorcraft one died in three years or so. Anything else I should look for or get it?
 
Nothing is wrong with expansion valve right now, but I like to have that just in case something goes wrong.

For your own sanity, I hope it doesn’t get to that point. I think the shop manuals say it’s 8-10hrs labor to replace the expansion valve. Unless you really like the car like myself and some others, it’s not worth the value of the car to spend time or money replacing it.

You should be good though. From what most have said, even a few members who completely shredded their compressors just replaced it and the condenser + drier and were good to go. The theory is most modern condensers have such small passages that the shrapnel gets caught in the condenser channels before reaching the expansion valve.

Best of luck
 
For your own sanity, I hope it doesn’t get to that point. I think the shop manuals say it’s 8-10hrs labor to replace the expansion valve. Unless you really like the car like myself and some others, it’s not worth the value of the car to spend time or money replacing it.

You should be good though. From what most have said, even a few members who completely shredded their compressors just replaced it and the condenser + drier and were good to go. The theory is most modern condensers have such small passages that the shrapnel gets caught in the condenser channels before reaching the expansion valve.

Best of luck

Thanks Broseph. Yeah, I really like the car, but I think car hates me. Keeps breaking down on me when I'm heading to somewhere, not the other way around. Also, corrosion beginning to appear all over the car. No. Not the steel part of the car. Aluminum parts are.

Joke a side, I don't mind working on the car. I do have second car (86' Monte Carlo SS. Body is restored. Working on inside) so taking our beloved LS for a while is no problem. Hopefully, two motorcycle will join soon (restoring 82 Kawasaki GPz750 and 89 ZX-7. ZX-7 is almost done) so as far as the daily driver or to get around, shouldn't be a problem while LS is down. Also have son next to me so worst case scenario, I will drag him out to help me!
 

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