Bugout4x4

Very good point, It is just like working with hot hydraulic systems and lines.

4.3L XJ

I am going to disagree here too. O rings are just butyl rubber and after time they loose their round shape and conform to what they are sealing. If they tighten up, which I haven't seen yet, it is because they are absorbing refrigerant or oil. That is somewhat a possibility in older O rings, since the old black ones are good for R12 but will allow the lighter compounds in R134A to seep through. Just about everybody has the green ones now, so not an issue. As far as the rings go, if you have to replace one, you need to replace them all because the next one is getting ready to go. Besides, they are cheap

PatHenry

Ok, awesome advice guys - thanks!

So eye protection is key - I do like seeing. Extra care dealing with old lines since I'd prefer to not replace stuff I don't have to.

So prelimary results:
I jumped the compressor and it did kick on. I only ran it for like 1.5s before disconnecting it. So at least from a preliminary standpoint I can assume the compressor is ok.
I poked the pressure fitting and got nothing. I did this a couple times to make sure I was opening the port and could see it opening. I'm assuming that if there was some pressure in the system that I'd at least hear the "air escaping" type hiss. So this means I'm pretty much empty/flat, right?

So my next step is to see about a vacuum pump and gauges, right? I'm of the same mind as Jordan - something that's well reviewed but a bit more expensive over the El cheapo. Obviously I don't need a pro-grade, daily use sort of set, so any mid grade recommendations are welcome.

Assuming I can get a decent gauge set and either buy or rent a pump without breaking the bank. I definitely think I'll do the o-ring replacement up front. I have no idea what/when the last time the system was in working order was, but like bugout mentioned, I won't have equipment to recover freon if it's leaking badly and I'm pretty sure (especially in MA) that it's illegal (and poor manners) to release refridgerent into the air.

Also my e-fan runs and I replaced the fan clutch 6m ago and have been a steady 207-ish since then. If I have to replace it again it's under warranty and not a big deal.

kbeam418

Yep if I do it for a friend/customer I'll do everything to make sure it's done right and will last. My own stuff I tend to do what is easiest (non-critical stuff not mechanical or safety issues of course) especially since my Jeep is my beater and not my primary car. I get the not doing it twice at your' job because I'm the same way if I'm doing it it's getting done the right way even if takes twice as long.

jordan96xj

PatHenry,


Here is the kit I went with. The price was pretty decent, and quality ended up being very adequate.


XtremepowerUS Air Vacuum Pump HVAC A/C Refrigeration Kit AC Manifold Gauge Set
by XtremepowerUS
Link: http://a.co/5EiWYil

Bugout4x4

Yep you should have got a hiss if it still had pressure, A flat empty system is where the O-ring issue comes in. If there had been even just a little pressure I might have agreed the O-rings could be OK because the pressure kept them sealed. But now you can bet oxygen has got back into the system and oxygen is not friendly to O-ring materials. And right on, you now know the compressor and fan work as they should!

I am using a harbor freight set right now which I have been using for over ten years and serviced a LOT of systems with it. The key is storage when you are not using it. The hoses and O-rings in the hose fittings will dry out. This is the major fail on all sets. Remove the lines when you are done and put them in gallon ziplock bags. Don't throw away the little plastic covers that come on the gauge connector fittings and put these back on when done also to keep air from getting to the inside of the gauges, they have diaphragms and O-rings in them too.

Pretty sure it's a standard world wide, But everyone does it. It all still leaks out into the atmosphere from the vehicle systems anyway right? Personally I think it was all BS invented to sell A/C components, retrofits and systems. And the R12 to 134 conversions were definitely a scam. 134 works absolutely fine in R12 systems, been doing it since the whole mess started.

But there is nothing wrong with being prudent, even if it is just to prevent the cost of wasted refrigerant, it's not cheap and without proper evacuation and recovery equipment it will indeed be wasted.

Yep, need gauges with the fitting adapters for the R12 system which it has right? Not that it makes much difference but we need to find this out. Someone may have already converted it before you got it? R12 will be screw on service fittings and 134 will be larger quick connectors.

If you are going to change the O-rings you will need the quick connector release tool to fit the lines. What I have run into is that a lot of the QC release tool sets don't come with that size so it becomes a separate purchase. How do the lines fit to the compressor? Do they go in the back or do they both go into a manifold on the top? These O-rings should be changed too and if it has the manifold they are special and will have to be ordered.

Time to call around and see who might rent you a vacuum pump. There are two types, electric and compressed air. If you don't have a good air compressor you will want the electric. But... If you want to buy an electric and have it for the future, they are only about 60 bucks and believe it or not even walmart sells them online.

I found that interesting... If even walmart sells them there must be a lot of folks out there doing this themselves. Not good at all for us who do it for a living... lol

Bugout4x4

Just took a look and I think you did well with this Jordan, and it is a very good recommendation. It is only a few bucks more than what this set complete would cost from Harbor freight and it looks to be better quality. Pump and gauges.

Sorry... I should have checked your link before making my earlier statement...

Bugout4x4

I kind of figured that was the case man. And if it had kept some of the pressure against those seals I would agree it's not that critical. But my concern was that it was completely flat and now oxygen got back in. This makes all the difference. We have to also remember that over time under pressure these get deformed and retain this deformity. Once deformed they don't usually go back where they were and seal correctly if the system goes completely flat and they back themselves off the mating surfaces. They tend to get squished flat and stay that way.

rheacox

I don't think I saw anyone mention this yet but it might also be worth replacing the schrader valve cores where the gauges connect. Worked on an '89 Town Car that kept losing refrigerant and that's all the problem turned out to be.

Bugout4x4

Absolutely! Even if you have the fitting seal caps it will leak past these also.

Good catch.

rheacox

I bring that up and it only just dawns on me that my Jeep is probably leaking refrigerant because of this too... taking the low side port cap off I sometimes get a very faint hiss...

So, might be a bit off topic but pertinent to the OP as well, does anybody know what schrader valve cores to get/where to get them? Was told they're all different when I got them for that Lincoln.

PatHenry

I think that it's R134 - I seem to remember seeing the stickers under the hood and I'm pretty sure the service ports were the quick connect style with a screw on dust cap. Obviously I'll double check this to be certain.

The lines definitely run into the back of the compressor and not the top.

I do have an air compressor and my Dad has at least one himself. However they're both at my Parents' house (6 miles away) so it may be just more convenient to get a little electric pump.

I looked at the kit that Jordan suggested and it seemed to be a good deal and had a lot of satisfied customers. At the moment I'm leaning toward that, but I'll do a little more research and look into the air compressor type pumps. I definitely don't mind spending money on tools - I bought a bunch of things over the years I owned my last Jeep and found myself getting more use than I expected out of them.

So I've heard the accumulator and schrader valves mentioned as things that are good to replace. Considering the fact that I'll be pulling connectors and getting my hands dirty under the hood anyway, are there any other components that I should (if nothing else, consider) replace before I put the thing back together and fill it?

Re: A lot of people buying pumps and it being bad for pro shops -- I don't think there's anything to worry about there. It's mostly us slightly nutty folks that insist on not letting go of our "waaaay past their expected service life" vehicles. Even for me, I have the luxury of being able to tinker with my XJ since it's not my DD/Family vehicle. If the A/C went out in the family car I would be compelled to take it to a shop since I'd need it fixed and fixed quickly. (Small children are challenging enough when they're comfortable.. )

rheacox

The hard liquid line that has the orifice tube in it should be replaced. It's a pretty cheap part.

Also, I've heard some people say to replace the condenser if you have the rest of the system open since the new style ones can't be flushed. Seems like overkill to me but if yours has a bunch of crushed fins I'd say maybe replace it unless you're on a very tight budget.

Bugout4x4

Sounds like you are good to go forward. I was joking about getting put out of business, I have always helped friends and family do it themselves if they are up to it.

Bugout4x4

All you have to do is ask and make sure they are made for A/C systems. Most auto stores will have or can get them. The little O-ring and seat seal in the schrader valve for A/C is a different material than it is for tires.