CubanGT

iTrader: (3)

As long as its taken me to finally rebuilt the compressor, get it back in the car, new dryer, new orfice filter, 4 cans of freon and 3 cans of oil.

Took the compressor apart, replaced the 2 o-rings, the 2 flat gaskets, the shaft seal. Installed it last week and tonight had my uncle check it out.. we hooked up the gauges, tested for leaks.. no leaks after 30 minutes on the vacuum.. So began by putting in the oil, 2 cans then 1 can of freon. At this point the gauges read at 90 both.. and no matter when we turned on the ac or off the pressure never changed / dropped.

We can hear the clutch engage, and the air is cool, but he saids that the pressure should drop when the ac kicks in..

Can anyone offer any suggestions? What else we can check or try? We left everythign connected so we can try again tomorrow when its warmer to see if the cool air we felt was in fact from the freon and not the cold night..

thanks.

LT1/TA

iTrader: (9)

The compressor may need one of these control valves, unless the compressor was not reassembled correctly.Just curious how much oil did you put in the system?
Here is a link to the control valve.

http://www.ackits.com/merchant.mvc?S...rControlValves

jam01

you put 4 cans of freon and 3 cans of oil, that is too much oil and probably too much freon. i would take it too a shop and have it vacuumed checked for leaks, have them put the correct amount of oil and freon in the system.

chevymec

iTrader: (19)

You should always put oil directly into the compressor when starting out fresh. Sounds like the valves arn't operation correctly and the compressor isn't pumping.

Intimidator02SS

1st, 4 cans of freon? My car takes (I believe) 1.5 lbs, which is 2 cans of freon.
2nd, I see where you only put 1 can in before pressures were at 90psi. You state you can hear the clutch engage, but the pressures do not change. Possibly the clutch air gap is incorrect...?? The clutch may engage but is still not turning the compressor. Thats about the only explanation.

CubanGT

iTrader: (3)

First off i bought 4 cans of freon, didnt put in 4 cans.. and bought 3 of the 3oz cans of oil which is what is recommended and this point only put 2 cans in. The system has been pressure treated and no leaks.. it was checked for leaks prior to any freon or oil( all without turning on the a/c. No leaks detected so 2 cans of oil were put in first. Then 1 can of freon. A/c started to blow cool, but then again it was a cool night.. tried again yesterday mid day when it was warm.. and still was able to get cool, pressure rose up to 100 then to 110 and when car was turned off, the pressure dropped back to 90.

The control valve o-ring was replaced as well while it was apart.

chevymec

iTrader: (19)

What were both pressures reading?

slow

iTrader: (7)

what kind of car?

The ls1 f-car only takes 1.5# and if you added oil without flushing the old stuff out, your over full of oil and you will have poor performance even with the correct refrigrerant charge.

Ryan

CubanGT

iTrader: (3)

With the car off, low pressure was reading 95 and high pressure was reading 105..
With the car on and a/c on the low was reading 100 and the high went up to 190

A/C blows cold and seems to work, just curious as to why a system readings werent changing when the system was turned on.

LT1/TA

iTrader: (9)

Mine did the exact same thing with the low side pressure readings,I pulled mine back apart and made sure the plates and gaskets were in correct order.I think one of my plate gaskets was turned wrong,put it back together and it works great.

I would pull it back apart and give it a good inspection.

CubanGT

iTrader: (3)

I keep trying the a/c everyday after work and it cools the car.. its def not as cold as it use to be few years back(since the car sat for 2yrs) but it is getting cold, so is there really anything else to do? I mean.. if its cooling, then the rebuild worked and its holding freon.. so the question is does it really need the last can of oil that it calls for? or leave it alone and just check from time to time..

LS14EVR

iTrader: (3)

I'm a newb, but don't these have to be vacuumed out first, then filled? Or is that what you have done and everyone is assuming this.

chevymec

iTrader: (19)

The low side should be about 30-50 psi depending on ambiant temp, with the ac on, 100 psi is not correct. I went back and didnt see where you flushed the system , or replaced the orfice tube / expansion valve or dryer. These are a must when the system is being serviced like a compressor replacement. It still acts like there is a restriction on the low side or the compressor isnt pumping on the low side.

CubanGT

iTrader: (3)

The system was vacuumed out.. did that first and during the process didnt find any vacuum leaks.. so began the process of adding the oil and freon. The dryer was replaced, the filter in the line was also replaced.

LS14EVR

iTrader: (3)

Ok cool on the vacuum.

Jays_SSZ28

iTrader: (2)

At 100 psi the temperature is 87 degrees.

You can't effectively check for leaks with a vacuum pump.

Pressurized cans of oil contain 2 ounces of oil and one ounce of refrigerant, read the fine print.

If you had the system apart and flushed you should have bought a bottle of PAG 150 and poured 8 ounces of it in various parts of the system, then put the system back together, evacuated it (vacuum pump) and added two 12 ounce cans of refrigerant.

Now having done what you did you have no clue how much oil is in it, no clue how much refrigerant is in it, you now have a problem and not knowing this pretty much leaves you with no choice other than redo the job.

Flush everything except the drier and compressor.
Drain the compressor.
Make sure you have the right orifice tube in it.
Add oil.
Put it together.
Pressure test it.
Run it on a vacuum pump.
Add 24 ounces of refrigerant.

samson_420

iTrader: (1)

^ Totally agreed . . . 95% of time you can't BS the AC system into working.