After looking in the archives, I'm a little confused on some of these questions.

This is a 77 F150/460. I dont know what the history of the AC is, ie: it was working at one time but I dont know what kind of gas was in it last. It's empty now.

I want to put R-134 in it.

Can I put the R-134 and the new Oil in there and expect it to work without any trouble? (The kit from AutoZone has it all)
I'm gonna put the Dye in there as well.

Will this old Compressor (assuming it worked) work with the new Oil for R-134?

Should I use the "Ester Oil" ?

Who has the experience? I'm getting real close to needing the answeres. Been working on it for a couple of weeks now.

I'm anxiously awaiting your Replies. Hoppy

 

If it has been a long time, say over a year since the AC was turned on and working, then you probably have dried out seals. Recharging the system will be hit or miss if you don't know when it worked last. You could try one of those 134 conversion kits and hope for the best, but my guess is that unless the AC is working at least a little, you will most likely need to purge the system and replace seals etc then recharge.

Good Luck,

Jim Henderson

 

Thanks Jim.
I had the Idea of putting some Hi-Speed air across(not through) the Various parts to siphon out any liquid left in there.

I guess I'll have to drain the Compressor by hand somehow, and pour in some Polyester oil, and crank it over a few times. The Kit recommends 12 times.

Then go ahead with putting in the Polyester Oil that comes in the Kit. Then the R-134, and then the Dye. I think that Dye shows up under a "Black Light" like some Bar's had a few years ago.
It was wiered to see the White shirts and Teeth shine so brightly in the bar and nothing else show up.

I hope the dye is not needed, but I think the Previous Owner had some trouble with the AC.

Is there an "Orfice" or "Filter" in that system that needs replacing just on accounta becuz?

Hoppy

 

You can just put the conversion kits on without draining the old oil out of the compressor.

I would get the autozone conversion kit and try to charge your system first. More than likely the compressor seals are going to be shot, also probably going to be leaking at other seals. If the compressor is bad then you are only out like 45 bucks for the kit, but you don't have to buy the fittings next time. Get you a new compressor set-up for the 134 and drier and hopefully you should be good to go then.

Chris
79 F-150
79 mustang

 

Thanks Chris.
I asked around today and found out just what you said is probably true.

I also found out purchasing Freeze12 requires a license the same as R-12, so there's no reason to go that route.

R-134 it is, and hopefully I dont have any trouble with the Dessicant bag coming apart.

 

Go to www.aircondition.com the techs there are great! They will help you. Art

 

Go to Aircondition.com ask for advise.

 

Do more research on your R-12 to 134-A conversion.
The "quick fix" kits only address part of the picture.
After three months of research,parts location, and work, I just completed total ac overhauls on '73 and '79 model pickups.

Here are some things for you to consider:

-- R-134A molecules are smaller than R-12 which is of course what your system was designed to use. Because of this, 134A is more prone to leaking than R-12. To remedy this, use of "barrier" type hoses as replacements for your factory hoses is suggested (required). Some schools of thought feel that factory R-12 lines have had their pores "saturated" with R-12 mineral oil by previous use will satisfactorily suspend R134A leakage, I don't know for sure.

-- I would suggest that you replace all of the O-rings in your system. They are found at every connection. Make sure to purchase O-rings that are compatible with R134A refrigerant (which will be R-12 compatible as well) in case you decide to go with 134A now or are forced to go with it later due to R-12 shortage/cost.

-- Compressor shaft seals are many times the weakest link in the system and are prone to leak with age, especially if the system has been lacking oil and/or not been operated for a long period of time and thus not lubricating the seal with refrigerant oil. You can replace the seal or just replace the compressor WITH A NEW ONE. I have had nothing but trouble out of remanufactured compressors and would not reccommend them.

-- Here's where the tough decision is. The evaporator and condenser sizes (i.e. fins per inch) in your system were designed
for R-12 performance specs. R134a performance specs are different (operate under higher pressures, etc.). With this in mind, you generally will not encounter as strong a performance out of an R-12 system running on 134a. I'm sure you have heard of converted systems not performing well at idle or in high traffic. It is because 134A requires heavier duty condensers and evaporators to maintain performance equal to that of R-12.

-- Lastly, which ever way you go, thouroughly flush your system so as to remove all old residue and contaminants and to ensure that you don't mix refrigerants and oils.

I have spent hundreds of dollars and countless hours trying to make the best decisions I could with these old air conditioning systems. There is a lot of research to do to get it right. I have chosen to stick with R-12 as long as I can. Too many things to go wrong in changing refrigerants as you will see with further research (oil miscibility, fittings, tools, hoses, expansion valve/block compatibility/specs, etc.). Hopefully this will help you and other ford truck oweners out there. There's more to it than what I have listed and it is quite expensive. Think about aspects of the job that you can have a qualified shop perform (flushing, etc.). Old York/Tecumseh compressors are rare these days but can still be purchased new or you may want to go with a different one altogether.

As suggested in other responses, check out the ac forums, lots to learn there.

Good Luck,
chillyman

 

R134 is a bad idea.
1) it leaks
2)it does not cool that well
3) The required oil will bring enough water with it to destroy the system in 3 or 4 years.
R134 may be OK for a system designed for it but it is a very bad idea for a R12 system

Some interesting reading

There are only two O.E. approved refrigerants and yet SNAP has >approved
>over 25 different freon replacements.
>However, SNAP does not do any testing of these freon in systems
>to determine their useability in automotive
>systems. Go to this site and verify if you doubt this
>information:
>http://www.macsw.org/macs.asp?mfurl=training.html
>
>R134a and R12 is recyclable in the field and therefore is overall
>a good choice for both satisfying the customer and
>the environment. Test data for 134a is readily available for
>a multitude of vehicles. The various other refrigerants don't
>have the same test data- MACS is currently holding AC information
>clinics here in California regarding the new BAR
>regulations and blends. From what I've been told and I'll find
>out specifically tomorrow when I go to one of their
>clinics, they are very harsh on the blends because of
>fractionation.

True blends do lose some performance when they leak (fractionate),
however, some blends, such as R406A (Autofrost) and R414A
(then Chillit), were EPA tested in leaking cars in a controlled
experiment, and compared to R12, R134a, and other blends. With
a given amount of charge loss, R406A/R414A still out performed
all the others. ALso when leaking R406A/R414A systems have fractionated
due to leaking and were then "topped off" (with same refrigerant),
yes there was a performance loss, but only 5% or so, and hardly
noticeable. Even with the fractionation/topoff performance loss,
they still outperformed R12 and esp R134a systems and other blends.
So MACS is correct about fractionation and performance loss, but
they dont mention that the loss is so tiny, that is not noticable
and still outperforms R134a.
>
>How does the refrigerant transport the lubricant after it's
>fractionated? Find that data somewhere on the blends.
>Why doesn't O.E. use them.

R406A/R414A still transport their lubricant fine (mineral oil).
Ask why MACS and the OE's just push "PAG" oil only? OEs fight
tooth and nail against POE (ester) oil for R134a retrofits. MACS
and the OEs argue that PAG is a better lubricant than POE, which is
true, but not by much, considering that most auto A/C compressors
only run a few months total over their entire lifetimes.

The stationary HVAC industry (for R134a and HFC refrigerants)
gave up on PAG oil back in 1992 or so and went with POE (esters),
and only in metal cans (to stop moisture coming in as plastic
bottles do). POE oils only absorb moisture 10-100X more than
do mineral oils used by R12 (and Autofrost). PAG oils are more like
1000X or more moisture absorbing. PAG oils (except daphne or
expensive double end capped) are extremely sensitive to chlorides
(small amounts of R12 or HCFCs or even coatings on pipes left
over from R12). POE can tolerate these. Why do you think OEs
and MACS want R134a retros to use PAG? so the chlorides can
make them fail quicker?

Do GM and MACS give tech the training that PAG oils can
suck in moisture upto 10,000X more than mineral oil? How about
almost all replacemnt R134a dryers having plugs that dont seal tight?
Do you hear them Suck or blow pulling out the shipping plugs?
If you dont hear them suck or blow, then plugs are probably not
air tight and they "breathe" in the warehouse as the atmosphere pres
changes and become water logged before you install them. Many
PAG oils boil (in a vacuum) before the water boils, so pulling
a vacuum will not dry out wet PAG oil systems like it dried out
mineral oil R12 systems.

The way large numbers of 134a evaporators are failing "right after"
the 3 year warranty is over seems to suggest many of these 134a
systems started life with 100ppm or more (intentional???)
of moisture in
them or more, slowly forming HF (acid) which eats away at the evaporator,
timed so that it fails just after the warranty. The standard for
refrigerants is 10ppm moisture and systems with 10ppm or less
moisture will run for many years and have no inside corrosion
or acids forming, even with PAG oil and R134a.

Now after your evaporater eats thru and leaks, you go get it serviced
by a "compentent MACS shop". They go by the book,
and clean up the system,
flush it with 141b solvent (contains chlorinated R-141b!), new dryer,
(that is most probably all ready wet), new evaporator, and fresh
GM PAG oil. They pull a vacuum for an hour or so which removes the
air, but not much of the moisture, recharge with R134a and you are off.

That new GM PAG oil is in a plastic bottle (remember that HVAC
industry went to metal cans for POE oil, that is 100X less moisture
grabbing than PAG). This replacement PAG oil is probably between
800 and 1000ppm moisture, right out of the unopened bottle, and will
climb to over 4000ppm if left exposed to the air for any significant
length of time. See URL www.autofrost.com/wetpag.pdf for a lab report
from Integral Sciences, the premiere refrigerant analysis testing
standards lab. It shows new unopened bottles (plastic) of GM and
Delco PAG oil at over 800ppm moisture! One had might as well urinate
into the system before closing it up with that much moisture.

Now in a couple months, all that moisture has generated enough acid
to fail the condenser or maybe the evaporator again. Customer
is screwed again.. and so this just repeats no matter how good the
shop is at fixing it or even with "proper" procedures..
It is damn near
impossible to ever get a R134a system dry again with PAG oil...
AFter market guys often use POE oil (less moisture absorbing) or
PAO (ROC-OIL - polyalpha+ is acsource.com's brand of this oil) from
OZ that appears to be mineral oil based and somehow claims to be
enough miscible with R134a (and all others) to return to the compressor.

Other solutions are to use Cryo-Chem's Tune-air kit, that contains
"Dry-Pak" (SS02A) silicone dehydrant, that chemically reacts with
the moisture and converts it into harmless silicone oil so it will
not take part in the acid forming reactions and cause corrosion.
"Cooltop" (GHG-X8) refrigerant incorportates Dry-Pak for this reason.

But going to a Dealer or MACS shop, will most often get you loaded
up with WET PAG oil, and failing again after less than 6 months,
with $1500-$2000 bill each time.

Dupont originally wanted to make R-134, not R-134a, another "isomer"
of tetrafluoroethane which was MISCIBLE in mineral oil and would have
worked in old R12 cars and new R134 cars without creating a crisis.
The "committee of 11" voted 8-3 (car OEMs and chemical co.) to kill
R134 and make R134a instead back in 1989, so that stable mineral oil
would not work and special (I.E. moisture grabbing life limiting PAG
oil could be developed and used instead). Dupont even had developed
and patented a "fluorinated mineral oil" that was stable like mineral
oil and would work with R134a! MACS and the establishment seems to
have stopped that also.

Senior Fellow Chemist Don Bivens @ Dupont
invented a series of blends called MP39, MP66, MP52 that became
known as R-401A / R-401B / R-401C comprised of R22/R152a/R124. Although
they did not carry mineral oil well (this was stated upfront),
they did work very well in alkylbenzene (AB) oil, (brand zerol), that
is a highly refined form of mineral oil and unlike PAG/POE is a
stable, non moisture grabbing oil. R-401C (used) to work fine in
85% AB / 15% mineral oil, so you didnt have to drain out all the MO.

MACS and the Auto industry raised so much hell
and issued an edict that
no chemical company could make a non R134a refrigerant or
a blend component or sell non R134a to third parties for resale
to auto industry...or they would be boycotted on their entire
product line (like paints and plastics). Dupont gave in and
said "yes sir", and took MP52/R401C off the US market! it was
even EPA approved at the time. Atochem did not submit FX-56
(R-409A) to EPA SNAP for MVAC approval,only HVAC.. It is another good
automotive (but illegal now) refrigerant in MVAC if used with stable
AB oil. MACS went as far to tear up papers from me and others
such as Dupont from the 1991 Halon and CFC alternatives Conference
after the EPA had accepted them for publication. Any paper that
wasnt pro R134a or PAG oil got killed... and hence they became the
"only" solution...

MACS and the auto industry have now achieved their goal...
You are supposed to buy a new car every 3 years now if you
want your A/C to work. Once it goes over 3 years old it
will soon become "unservicable" or very expensive to keep running
if it is a R134a system and using PAG oil like they want you to use.

Aftermarket compressor rebuilders did just was MACS told them to
do.. Fill the rebuilt compressor with PAG oil... and the plugs
dont seal, so when it sets in the warehouse, just like the dryers,
they "breathe" and suck in moisture as the weather changes.. in
fact so much moisture into the PAG oil, that the compressor is
rusted stuck before the DIY mechanic buys it to install in his car...
Ask EVAPCO about that one..

>
>I know of several fleets that are perfectly happy with blends
>but I don't think that we need 25+ refrigerants floating
>around in the market place when each one is supposed to have
>unique fittings and seperate recovery systems. Let's
>see Mr. Customer, your bill for just checking your AC system
>has gone from 1 hour of diagnostic time to 10 hours
>so that I can pay for all of the seperate recovery machines I
>have in my shop.

EPA "requires" unique fittings, and recovery systems for blends
since MACS lobbied that to the EPA in order to impede blends
as much as possible. MACS also lobbied in recovery/recycle of R-134a
and the need for more recovery equipment (illegal to vent) to
the EPA, even though R134a has zero ODP (no ozone depletion).
Computer "duster" cans are just R134a and they are legal to vent
by definition. Could it be that Ward Atkinson's (tech director of
MACS) good buddy, Art Hobbs, happened to work for Four Seasons
at the time, needed an excuse/law to be able to sell
everyone a 2nd recycle/recovery machine for R134a, right after
they had sold them one for R12? Computer duster cans of R134a
are legal to vent, but why not R134a for a car A/C?

>Or I could just vent it to the atmosphere and hope that the
>EPA doesn't fine me the $15,000 if they catch me. Or I'll
>incinerate it locally, which is also environmentally friendly?
>

What if you hooked up a hose to you R134a car and blew it off
and used that to dust off your computer keyboard and shop?
Just equiv to two "dust off" cans from Sams club?

>When at all possible use the freon that came if the vehicle
>as long as it's cost effective. If not then your best
>alternative for cooling and lubrication is R134a because
>it's safe and easily serviceable by shops everywhere.

 

Just my wanted to tell you how the retro kit worked for me .

The AC in my 79 bronco hadn't been run in years . I didn't evacuate the system (but it was empty) . I used retro kit and the AC worked but I did need to install an extra can of r-134 . 6 months later ad it still works great .