A/c compressor discharging while filling

[Canadian]

Hey guys, I had my a/c compressor lines disconnected and had the compressor removed for a number of days doing my engine swap (2001 with VQ35de engine), so I assumed I lost my "charge" in the process. So today since I had a can of Duracool laying around and I have the fill tool/gauge from previously recharging the system I decided to put it in.

I followed this video exactly, skip to 1:30

All seemed to be going well, the system took in the contents of the can, the a/c started blowing pretty cold, and then the video says the rev the engine and hold rpm to circulate, as soon as i did that, I hit about 1600rpm and the compressor made a weird noise and made a discharge of compressed air noise. I thought that was odd, tried revving again, it discharged again, I let the rpms fall and noticed the air wasnt blowing cold anymore. Looked under the car, and sure enough, some green fluid had purged onto the floor.

Im not to worried about losing the can of fluid, as its been in the garage some years, but Id still like to fill this system and not have it discharge on me, should I just avoid revving the engine? All seemed well before I did that, but obviously if I were to be driving the truck the rpms would rise.

What do you guys suggest?

[bushnut]

you've got a hole somewhere, or a leaky seal at a joint or connection...I'd look around till I found it.

[adamzan]

If it is leaving stuff on the floor, then the leak should be big enough for you to spot by eye. Did you replace the o rings on the connections to the compressor when you had the lines off. You're not really supposed to re use them.

[PeteyPathy]

Several issues here. First you opened system without first recovering coolant from it. Second the system was left open several days, this means you MUST replace drier. Third you didn't vacuum system prior to recharging. Forth you didn't replace o-rings on a/c lines.

 

Any of these things will stop system from working properly. As you said there was fluid (green color indicates leak detection dye) on floor you should be able to find where its leaking from. Clogged drier creates too much pressure in lines and can blow them or evap core drier removes water vapor from system. Bad o-ring=leak.

 

When installing new drier it should not be open to atmosphere for more than 5 mins (in very humid deep south where i live) more than that and good chance it will pick up too much water from air causing failure. Filling system from can preloaded with oil/sealant repeatedly over time fills system with liquid instead of freon. It will still cool... Sort of but will not work anywhere close to correctly.

 

Finally there is reason you are supposed to be certified to do a/c work its more than just shoot a can in it for system to work properly.

[adamzan]

In the us ac work is fairly cheap. Up here in Canada you pretty much get raped by shops. So much so that I bought a set of gauges and a cheap vacuum pump from harbor freight. Nothing against you I just hate when people suggest being certified pr taking it somewhere on a forum designed to help the do it yourselfer.

[Canadian]

Forth you didn't replace o-rings on a/c lines.

As you said there was fluid (green color indicates leak detection dye) on floor you should be able to find where its leaking from.

 

 

If it is leaving stuff on the floor, then the leak should be big enough for you to spot by eye. Did you replace the o rings on the connections to the compressor when you had the lines off. You're not really supposed to re use them.

 

I did replace the o-rings. Why are you assuming I did not Peteypath?

 

The fluid that was discharged was not from a leak, it was from the discharge valve on the backside of the compressor, Im assuming pressure became to high or whatever the safety precautions are built into the compressor causing it to discharge.

 

I only tried one can of the duracool since its what I had. I expect I will need to buy 2-3 cans when i actually try and fill it, they sell a few different types of fill aswell, leak seak, oils, general refrigerant. Id love any DIY help i can get, as adam said, in canada they charge a few hundred + for this service. Since I already have the install valve/gauge, and this is my winter beater/boat hauler, Im trying to keep the cost low.

 

Cheers

[PeteyPathy]

It's not any cheaper here to get a/c work done.

 

You didn't mention having replaced o-rings.

 

If over pressure valve or pop off valve as its somtimes called is where it discharged. See the above post by me where i DIY info regarding a/c drier that is bad causing excessive pressure in system. I'd also check the high pressure switch for proper operation.

 

I'm sorry if pointing out your mistakes offended you. I don't recall saying you should not touch a/c take it to shop. I said there is reason people get certified to do a/c, more to it than squirting a can in it. In my book knowing what i did wrong is first step in learning how to do a job RIGHT.

 

Like adamzan said harbor freight, cheap vacuum pump.

 

Good luck

[Canadian]

I didnt get offended. I just thought it was odd you ASSumed I didnt replace the o-rings, and I said it discharged and you again ASSumed I had some big obvious leak from those o-rings, when it was simply the discharge from the valve

 

We dont have harbor freight here, buying a vacuum pump isnt an option, is it necessary?

[PeteyPathy]

For system to operate correctly yes, vacuuming system is necessary. Also if you can would be great idea to blow compressed air through system to be sure there are no physical blockages in system. Remove both ends of both hoses and blow through each component individually opposite normal direction of flow. Sometimes when drier fails it allows what looks like little pebbles into system. They will clog condenser and evaporator. Doing this also blows out excessive oil that may be in system.

 

Normally you pull vacuum for 30 mins to an hour to be sure system is completely clear of contamination.