vacuuming a/c

[The Warden]

Regarding flushing the system, let me make sure I have it right...all you need is the kit and shop air? No other special tools?

My compressor's ready to be replaced, and I didn't flush the system out thoroughly last time I had the system apart...I tried, but with the tiny air compressor I was borrowing, it didn't work out very well. Also, I'm trying to get all the performance I can out of my a/c; mere ice cubes are insufficient, I want a blizzard so, anything I can do to help the a/c is beneficial (to the point where I'm seriously considering spending the $$ and going back to R-12). I can handle 30° weather, but I can't handle heat, AT ALL!! It may be cool in Pacifica, but not in the rest of the Bay Area during the summer...

Ideally, I want to upgrade to a parallel-flow condenser as well, but my thought is to combine that with an intercooler install, and put the I/C between the condenser and the radiator...

 

[sle2115]

Regarding flushing the system, let me make sure I have it right...all you need is the kit and shop air? No other special tools?

If you got the tools to separate the fittings, the kit and shop air is all you need. I would, of course, recommend a new orifice tube, new accumulator/drier and an inline filter, but that is your call. The flush will remove about any crud. Personally, the systems I have charged with R134a, I would put against R12 in performance. My experience (and that of several around here that do this for a living) is that R134a is more temperamental than R12, meaning that R12 can be a few pounds high/low with little performance depreciation. R134a on the other hand likes to be right on pressure wise and doesn't seem to be quite as consistent between vehicles. One may make lower duct temps without evap frosting at slightly lower/higher pressures than another vehicle. On mine, I just kind of play with the pressure, starting high and reducing to acceptable performance. I have found the 80% by weight rule to be about right as well.

 

[RLDSL]

Regarding flushing the system, let me make sure I have it right...all you need is the kit and shop air? No other special tools?

My compressor's ready to be replaced, and I didn't flush the system out thoroughly last time I had the system apart...I tried, but with the tiny air compressor I was borrowing, it didn't work out very well. Also, I'm trying to get all the performance I can out of my a/c; mere ice cubes are insufficient, I want a blizzard so, anything I can do to help the a/c is beneficial (to the point where I'm seriously considering spending the $$ and going back to R-12). I can handle 30° weather, but I can't handle heat, AT ALL!! It may be cool in Pacifica, but not in the rest of the Bay Area during the summer...

Ideally, I want to upgrade to a parallel-flow condenser as well, but my thought is to combine that with an intercooler install, and put the I/C between the condenser and the radiator...

It's not difficult. Run the flush through, then blow it out, keep in mind, the blow it out part is going to take quite a while and even with driers on your air line, if it's real humid out there is going to be moisture blowing through, and after a flush, you want to run a vacuum for a good long time to get all of the moisture out of the system.

If you want it to get good and cold on hot days, try a variable orifice valve. If it really gets hot where you are the things do wonders ( in cool climates, they don't seem to make much difference ) Adding a small electric pusher fan triggered by the AC will help a bunch in traffic
I've never fooled with the paralell flow condensors ( never really needed anything else after the before mentioned mods ) But if you go that route, you're going to have to make up some custom hoses to fit. so you'll either need a reasonably priced hose shop nearby or you'll need to buy a hose crimper and you can buy ends with various bends from places like nostalgic air parts

Watch your charge carefully, it doesn't take much overcharge to make an r134 system cool poorly

-------Robert

 

[typ4]

My buddy who has a shop got me an updated condensor and the variable orifice valve, the ac works awesome even on really hot days.
I will try to get the condensor info and post it.

 

[Exekiel69]

If anyone have some pics or manual based info about the orifice tube it would be great. I removed and replaced the OT the same way it was so either it was installed wrong (long side very dirty) or this truck has a very peculiar a/c system?



Thank You.

 

[LandscapeMan]

The picture of the orfice tube going into the freon high pressure side is going in upside down. Sorry. The dirty side of the original tube shows which way they are installed. You can see all the dirt it collected.

Thanks,
Sounds like we will be pulling it apart and flushing while were in there.

 

[The Warden]

If you got the tools to separate the fittings, the kit and shop air is all you need. I would, of course, recommend a new orifice tube, new accumulator/drier and an inline filter, but that is your call.

I replaced the orifice (with a blue orifice meant for an R-134a system) in 2004; should I do so again? I figure that it's a given that I need to replace the accumulator, and an inline filter sounds like a good idea.

If you want it to get good and cold on hot days, try a variable orifice valve. If it really gets hot where you are the things do wonders ( in cool climates, they don't seem to make much difference ) Adding a small electric pusher fan triggered by the AC will help a bunch in traffic

I've heard of the variable orifices, but I thought I heard somewhere that an orifice meant for a 134a system was better if available? I could certainly be mistaken; what are your thoughts there? And, I agree completely with the pusher fan; that setup is factory equipment in M-B diesels, and makes a world of difference for the a/c system. My old 300D's fan didn't work when I got the car, and when I replaced it, the a/c got noticeably cooler ESPECIALLY in traffic.

I've never fooled with the paralell flow condensors ( never really needed anything else after the before mentioned mods ) But if you go that route, you're going to have to make up some custom hoses to fit.

Yeah, that's what I figured...one of the reasons why I would want to couple that with an intercooler install. If I put an IC on my truck, I want the condenser forward of the IC (that seems to be the setup on most vehicles factory-equipped with an IC), so I would need custom hoses even if I used the factory unit.

I'm slowly but surely trying to make my truck comfortable to drive and to ride in...

 

[LandscapeMan]

nostalgic air parts

Watch your charge carefully, it doesn't take much overcharge to make an r134 system cool poorly

-------Robert

How do you check the charge? What is the correct charge level? I have been told that 2.5 cans is about the correct level? We put in 3. But have to pull the system back apart to flush and replace the r134. We also replaced the black can. Is that a accumulator or what is the correct term.

Thanks,
Charlie

 

[LandscapeMan]

Quote:
Originally Posted by RLDSL
It's not difficult. Run the flush through, then blow it out, keep in mind, the blow it out part is going to take quite a while and even with driers on your air line, if it's real humid out there is going to be moisture blowing through, and after a flush, you want to run a vacuum for a good long time to get all of the moisture out of the system.

-------Robert
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Any tips on where to hook up the flush and hoses to flush system. I though I read somewhere not to flush the compressor. Any truth to that?

Do Auto Parts stores carry the flush kits. Or is it better to Order from JC Whitney?


Thanks
Charlie
__________________
92 F-350 CC Dually
E40D

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Last edited by LandscapeMan : Yesterday at 01:44 AM.

 

[FordGuy100]

Sorry guys I havent read the thread, but my truck is still using R-12, at least I'm fairly surtain it does. So whats the advantages to R-134a over R-12?

 

[sle2115]

Sorry guys I havent read the thread, but my truck is still using R-12, at least I'm fairly surtain it does. So whats the advantages to R-134a over R-12?

None - just cheaper to replace. I like R12, but it is difficult to get and expansive when you find it.

 

[sle2115]

I would not flush the compressor. There is generally lube and such in there not to mention it would be difficult to get all the flush back out.

 

[argve]

I have used r134 in an r12 system with good success. Some say it will kill everything in short order but I have not seen this on any of the systems I have done. I picked up the conversion kit from Meijer supermarket in the auto section for like 40 bucks or so a few years back and my buddies truck is still running on it 5 years later - so I woudl say they work. Everything I read on it from my haynes manual says that just don't over charge with 134 and you'll do fine. I put 3 cans in The E and it filled it up to just under the poundage that was called for r12 about 90% which is what the manual said (80~90%) if memory serves.

The guys int he business call the kits I used "Death Kits" but again I haven't seen it on any of the 6 systems I have done. The ones that we had to go back and redo again leaked before hand so it's not surprising.... I ended up putting a leak stopper in the one for the E and found the leak... it was the schrader valve that was leaking and it sealed it up... Found it when I went to recharge again just because I was expecting it to be low at the start of the season (was doing recharge as a PM thing because I just figured it needed it - should have checked the operation first)...