a/c issues part III (or IV OR V) (1 Viewer)

[inacoma]

ok, so I searched (of course) and I am looking for someone that has possibly had the same issues as me or some sort of consensus on what has been done to fix.

On cooler days my a/c seems to work just fine, well enough to freeze me out.
On hot days (like today) my a/c just doesn't blow out cold air (it's not hot air, but it's not cool air either). The air is 'consistent' in quality on hot days, doesn't go up and down.

so I guess what i'm asking...can I get away with only replacing the a/c clutch or should I shoot for a full flush and refill (truck has 180k miles on it, mostly in california heat).

oh, and if I have the truck garaged all nite, then drive out the next am in hot weather, then the AC is just fine. But if the truck sits in the heat for any amount of time beyond that (parking lot), I can just forget about a cool ride home.

any assistance greatly appreciated. I have a very long trip ahead of me and would like to get this worked out soon.

thanks!

Kumar

 

[SteveLCetc]

If you look at the site window by the battery do you see bubbles?

 

[MoJ]

You've checked pressure levels?

 

[inacoma]

If you look at the site window by the battery do you see bubbles?

do i check this with the AC on or off?

As far as pressure levels, what is normal pressure? I am going to go out with my flashlight and check both now once I google some answers (or get replies from here or Mark Brodis (he's on IM with me right now)).

Kumar

 

[SteveLCetc]

Start it and have somebody run it at 1500 rpm with the AC on max. If you see bubbles in the little window you need freon. You might want to add oil too. The last time this happened to me (on an 85 4runner) I didn't add oil and I burned up a seal (which may have been going anyway which was why I was losing pressure).

Anyway, run it like that for a couple of minutes and you should not see bubbles. Mine was weak and I did that, and after a quarter can the bubbles cleared up. I'll have to wait until tomorrow to see if it's stronger...

 

[MoJ]

Couldn't tell you off the top of my head but go that route before spending the coin for new parts. Must of posted the same time as Steve - - his suggestion is the easiest and first clue that you may need to add coolant.

 

[inacoma]

Start it and have somebody run it at 1500 rpm with the AC on max. If you see bubbles in the little window you need freon. You might want to add oil too. The last time this happened to me (on an 85 4runner) I didn't add oil and I burned up a seal (which may have been going anyway which was why I was losing pressure).

Anyway, run it like that for a couple of minutes and you should not see bubbles. Mine was weak and I did that, and after a quarter can the bubbles cleared up. I'll have to wait until tomorrow to see if it's stronger...

ok, so here' what I found out.

I ran the rig as you stated above, the 'window' showed what looked to "microfoam" type bubbles. It was consistently milky looking like it consisted of a bunch of micro bubbles. Is this what people consider bubbles or do they need to be huge ones?

I couldn't check pressure as my gauges didn't seem to fit into the recessed hole where the valve is...unless of course, i'm looking at the wrong thing (it's on the compressor)

oh, and how much OIL should a fully evacuated system contain? I saw numbers on the amount of r134 but not the oil amount. I may just evacuate the system at a local shop and recharge it myself.

Kumar

 

[SteveLCetc]

ok, so here' what I found out.

I ran the rig as you stated above, the 'window' showed what looked to "microfoam" type bubbles. It was consistently milky looking like it consisted of a bunch of micro bubbles. Is this what people consider bubbles or do they need to be huge ones?

I couldn't check pressure as my gauges didn't seem to fit into the recessed hole where the valve is...unless of course, i'm looking at the wrong thing (it's on the compressor)

Kumar

Yep - that's what I had. Here's what I did. I got a little can of "oil - leakstop - o-ring rejuvenator" etc., and put that in. I still had bubbles, so I got a can of straight freon and started that slowly according to the instructions until the bubbles went away. That was about a quarter of a can and took about 5 or 10 minutes. Then it ran clear, which is what the factory manual says is what it should be. Now I have 3/4 of a can of freon left over, but what the heck.

 

[inacoma]

Yep - that's what I had. Here's what I did. I got a little can of "oil - leakstop - o-ring rejuvenator" etc., and put that in. I still had bubbles, so I got a can of straight freon and started that slowly according to the instructions until the bubbles went away. That was about a quarter of a can and took about 5 or 10 minutes. Then it ran clear, which is what the factory manual says is what it should be. Now I have 3/4 of a can of freon left over, but what the heck.

did you put an entire can of OIL in??? wouldn't that be too much and not leave enough room for the freon? my fsm shows with compressor off 57-85 psi.
which plug do you add the oil and freon to? I would look it up, but my fsm is at a friends house right now. I assume you add the freon while the AC is on full blast.

man, thanks for the help, this may just save me.

Kumar

 

[SteveLCetc]

I just used the littlest can of oil/o-ring tuneup etc. can from Autozone, then a can of freon. Actually then a 1/4 can of freon...

 

[inacoma]

I just used the littlest can of oil/o-ring tuneup etc. can from Autozone, then a can of freon. Actually then a 1/4 can of freon...

cool, i will do that. can you reply back to the thread tomorrow and let me know how it goes?

thanks!

Kumar

 

[SteveLCetc]

Yeppir.

 

[Rich]

I'm no expert on automotive AC. But I do know that just adding Freon to a R134 system "unitl the bubbles go away" can (not necessarily will) cause considerable harm. The minimum necessary equipment to reasonably service the system includes a proper set of gauges and an understanding of how to measure the low side and high side pressures and how to interpret the results while operatiing the AC and monitoring the ambeient condensor and ac vent temps.

Also note that the method specified by the factory manual for adding refrigerent on the high side is vastly different than the more common method of adding refrigerent on the low side. If you get it wrong, you will understand what the warnings on the can about explosions and instant frost bite are all about. Don't ever connect the little cans to the high side port.

My recommendation is to research the proper methods to service the AC or take it to a shop. While low refrigerent levels is probably the most common cause of poor performance, it is not the only cause. For R134 systems the sight glass is not considered very reliable, and for that reason has been omitted from many R134 systems.

For the older R12 systems adding Freon until the bubbles dissappered is an accepted practice. Those days are over for those of us driving late model vehicles.

 

[IdahoDoug]

I agree that you should strongly consider having the system serviced. It's not rocket science or expensive, but requires tools and knowledge to do correctly. Last time I had my system (good ol' R12), it cost me $75 at the Toyota dealership. Money well spent if the alternative is trashing $1000 worth of compressor and related and having a hot trip as well.

DougM

 

[inacoma]

I agree that you should strongly consider having the system serviced. It's not rocket science or expensive, but requires tools and knowledge to do correctly. Last time I had my system (good ol' R12), it cost me $75 at the Toyota dealership. Money well spent if the alternative is trashing $1000 worth of compressor and related and having a hot trip as well.

DougM

I remember reading a post about a dealership that did the window method even on the r134 (mainly because the FSM states to do it that way). I'm sure dealerships varry, and I'm afraid mine is one of those shortcut ones. I may go try to rent a gauge set (i've done this on window a/c units before). If I can't find a gauge set, then I will hunt down a shop that does this. It's just so hit and miss with shops, some of them know what they are doing and some just plain don't have a clue...better to have a monkey work on my truck in my driveway

thanks!

Kumar

 

[lurker]

I agree that you should strongly consider having the system serviced. It's not rocket science or expensive, but requires tools and knowledge to do correctly. Last time I had my system (good ol' R12), it cost me $75 at the Toyota dealership. Money well spent if the alternative is trashing $1000 worth of compressor and related and having a hot trip as well.

DougM

$1000 --------

I ran out side to check mine (TX heat!) and mine looks like cigarette smoke every now and then. Is this normal and my view glass is in front of the battery compartment, is this because my LC is a early 93 (R12)?

top no flow
bottom start of flow

 

[inacoma]

$1000 --------

I ran out side to check mine (TX heat!) and mine looks like cigarette smoke every now and then. Is this normal and my view glass is in front of the battery compartment, is this because my LC is a early 93 (R12)?

top no flow
bottom start of flow

yours looks ok. hopefully it feels ok too. i read in my fsm that the site bubble may show some bubbling at extreme temps...and that would be ok. however a lot of folks here don't think the site bubble is good for determining freon levels...except in r12 systems, like yours.

otherwise, yours looks "ok" given what you have provided.

I bought some r134a today with a built in gauge for the low side. I will be attempting to check my pressure then to refill if neccessary when the truck cools down as well as the ambient temperature.

Kumar

 

[lurker]

yours looks ok. hopefully it feels ok too. i read in my fsm that the site bubble may show some bubbling at extreme temps...and that would be ok. however a lot of folks here don't think the site bubble is good for determining freon levels...except in r12 systems, like yours.

otherwise, yours looks "ok" given what you have provided.

I bought some r134a today with a built in gauge for the low side. I will be attempting to check my pressure then to refill if neccessary when the truck cools down as well as the ambient temperature.

Kumar

Thanks for the info. it's had to tell when the FSM just states bubbling?

 

[inacoma]

Yeppir.

I was curios...my fsm shows that the low port is above the high port. however when I looke at the are in my truck, they both have caps that are labled "H". Is that generic for high pressure area and not indicitive of actual "high side" and "low side". What's the port that looks like a normal shraeder valve for?

Kumar

 

[SteveLCetc]

I ended up putting about 2 ounces of freon into the system before the bubbles quit. It's colder, and it still works

For you guys afraid to put your own freon in, (by the way freon is also R134 and a variety of other compounds:

http://computing-dictionary.thefreedictionary.com/Freon)

I find it inconceivable that adding 2 ounces to a weak system would hurt it...