sight glass in dryer

[Richard Cranium]

I've read that when the car is running, if you see bubbles in there, you've gopt a problem. What I see in mine is milky white liquid, but no bubbles.

Is what I'm seeing normal?

 

[trimmer]

Normally after the system has been on long enough for it to be working properly, the sight glass should be clear. It is normal to see bubbles on initial start up, should clear up after the system becomes stable. I think if you are seeing the oil (looks milky to me) and you are not cooling properly then try to add some freon. If it is still operating on R-12 I would upgrade it to R-134a. Not a hard or expensive process and most automotive repair shops can do it pretty quick or if you have the proper AC tools you can do it yourself and be very happy with the results. Is it cooling now? When it is right it will be clear. Hope his helps.

 

[Hemi Rebel]

Is your a/c cold?

 

[Mark B]

Milky would tend to indicate moisture in the system if I remember correctly. Has the system been changed to R134a? If so has the oil been changed also? Oil in R12 systems is supposedly not compatible with R134a and this may be what you're seeing. Otherwise if the system sat open for some time and was not properly vacuumed down there could be some water inside.

 

[benno440]

yeh agreed, change to R134, R12 is phased out now and extremely expensive and not as good.

 

[GrabberOrange69]

...also with R134 the sight glass is not used and you should see only clear (even if fully charged)...

 

[khryslerkid]

You don't want to mix the two. The r12 needs to be evacuated and most recommend changing the dryer.

I went to a shop a few years ago with a '92 Buick. The air wasn't working. They wanted $400. to change over to 34. I said I didn't want a whole system and compressor. They said it was just for the r34 and a new dryer. I said I'll let you know. Called two other places and they wanted the same amount.

So I went to Target, bought the kit for like 20.00 bucks. Removed one of the valve inlets. Nothing was in the system. Fastened the first bottle to the correct inlet. It took it all. Fastened the second bottle. Compressor started to operate and it used about half of that bottle. Cold air!

Now that lasted for about two years. Compressor's front seal was a little wet when I did this. So if you see any wetness at a connection or your front seal it may not last unless you repair. If someone has already changed the system over to r34, the fittings will be changed and there should be a tag on one of them.
When a system looses it's pressure, the compressor won't come on. Safety switch. You can jump this switch to check your compressor for operation. Not too long though.

 

[Richard Cranium]

Thanks for the input everyone. When i bought the car, the a/c was dead, but the compressor did turn on. Added a couple cans of R12 from a friend & it came back to life & blew nice cold air but went dead 2 weeks later. Tightened up all the connections under the hood (got 1/4 turn on the condensor & dryer lines) and a week ago, I added another can of R12 with dye. I checked all the connections under the hood with a black light and no leaks were detected. When I drove it last night, the a/c was still blowing fairly cold, but that's when I looked into the site glass and saw what I saw.

I do have 14 cans of R12, so keeping the system R12 isn't a problem for me, but obviously, I don't want to have to add a can every couple of weeks. I do have a line on a local person who I hear can work on these old systems and perhaps I'm better off taking it to him for proper evaluation.

Any input where typical problem areas might be on these old systems (69 Charger)?

 

[red 69 runner]

More than likely the evaporator is leaking if you didnt see any leaks under the hood an electronic leak detector will pick up leaks as well

 

[MoparMitch]

Yup, If you cant detect a leak under the hood, probably is a leak in the evap . You should be able to detect that leak by placing the probe of the electronic detector either in one of the outlet vents or near the a/c box under the dash.

 

[Richard Cranium]

Thanks for all the advise!

 

[hunt2elk]

I would go the r134a route also. I had several small cans of r12 that I put on ebay a couple of years ago and they sold for $45. each iirc. You could do that with your stash and use that $ for the conversion. It also is important to have the system pumped down to remove any air or moisture before recharging if it completely empty.

 

[Richard Cranium]

What is involved with the conversion? Is it just the Freon or do parts also get changed?

 

[Sixpactogo]

Richard,
I'm no expert on these old AC's by any means but........If you have a leak, it is usually at the compressor. The front seal on them (in my experience) has been the most problematic. I have three AC vehicles (65 Ply, 68 Charger & 78 Dodge truck) and have not had issues with any leaks other than the front seal. My truck has over 500K miles and I have replaced the front seal twice. I see there are a lot of guys wanting you to "upgrade" to 134 but I would do that as a last resort myself. IMO, the 134 does not cool as good as the R12 and since you have a supply of R12, I would use it. I have never had a refrigeration guy tell me that 134 is better. Only cheaper. Good luck whichever way you go. If you need a new front seal, I can get you a PN for it. There are a few around yet.

 

[Richard Cranium]

I would go the r134a route also. I had several small cans of r12 that I put on ebay a couple of years ago and they sold for $45. each

I just bought a dozen 14 oz cans yesterday @ $17.50 per can & the guy I bought them from has plenty left.


Edit: Just as a comparison, I just bought a 19 oz refill can for my work van @ $28.00.

 

[MoparMitch]

I just bought a dozen cans yesterday @ $17.50 per can & the guy I bought them from has plenty left.

Hey RC , are you sure thats not freeze 12 or another brand of drop in replacement for R12. The real deal R12 should be much more expensive than that. The last 30 lb cyliners of real R12 I sold before I got out of the Parts business in 2000, we were selling for $599.00

 

[hunt2elk]

Hey RC , are you sure thats not freeze 12 or another brand of drop in replacement for R12. The real deal R12 should be much more expensive than that. The last 30 lb cyliners of real R12 I sold before I got out of the Parts business in 2000, we were selling for $599.00

Yeah, the stuff I had was the original blend that we had left from the late 70's.

 

[kellycom]

r134 does not cool as good as r12. r143 is better for the environment when it gets release into the atmosphere than r12. that is why the change to r134.

the switch to r134 requires the service ports to be changed and the drier changed. since they cant be mixed and the service ports are different you have to evacuate the system anyway.

older mopars and newer mopars use an expansion valve instead of an orifice tube. GM and ford switched to them long ago. I'm not sure when chrysler stopped. but an expansion valve will cool better than an orifice tube if the system looses some freon. whether it be r12 or 134.

your site glass should be clear and have no bubbles. seeing bubbles in the site glass tells you the system has a leak and is low on freon. how low all depends on how cold the a/c is blowing. to check the temp put a thermometer in a vent with the blower on low and max a/c off. the coldest air the system will produce is with the blower on low. if the system is low you may also find that the compressor is cycling. the faster it cycles the lower on freon the system is.

r12 us worth it's weight in gold since it is not being produced anymore. so odds are you have gotten a r12 replacement. but not actual r12. r12 has been out of production since the mid-late 90's. r134 is good, just not as good as r12. but if you aren't going to fix the leaks. you're better off switching to 134 since it's abundant and way cheaper than real r12.

 

[Richard Cranium]

Hey RC , are you sure thats not freeze 12 or another brand of drop in replacement for R12. The real deal R12 should be much more expensive than that. The last 30 lb cyliners of real R12 I sold before I got out of the Parts business in 2000, we were selling for $599.00

Nope, it's the real McCoy R12. I found someone local who has a boatload of old cans at a reasonable price with no additional charge for the dust.

 

[trimmer]

Hey Richard, I am not trying to be a smart ***, but you need to get rid of that R12 before the EPA finds out you have it as the fine for having it could put a large dent in your business. Here in the south AC is a must and I was a certified AC man for cars. You can take a test on line to get the licenses you need to have that R12 on your property. I always hear of folks that think 134 is not as good as r12 but every car made after 1995 has 134 and you generally do not hear much complaints about it. As far as how to change it over there are many how-2s when you google it and many of them are correct. Another thing is if you change to the 134 the system will only require 3/4ths of the amount that it originally had. i.e. if it held 4lbs. now it only takes 3 lbs. to do the same job. Please post that you have gotten rid of all R12 and no longer have any on your property. I always hate to see good people have problems because they were unaware of these crazy rules. EPA will not be your friend.

try this link www.epa.gov/.../608fact.