[V8] Tools for A/C work

CB&D, LLC cbdllc at ntelos.net
Tue Jun 28 19:21:43 EDT 2005

I recharged my system and added the aerosol ester oil charge.  97 F here in
VA yesterday, A/C set to 68 F and auto fan speed dropped to low :)  Then I
hear from the back seat: "Dad, its cold in here!"

The only change I made was to remove the low side shrader valve insert and
install a 90 degree R-134a fitting to get the larger R-134a recharge hose

I converted a 1986 Ford Bronco the same way 4 years ago with no problems.

Snip from a FAQ:

How do you actually do the retrofit with the Interdynamics kit?

There are 5 steps: 1. EVACUATE the R-12, if there is any left in the system.
This must be done without venting (releasing the gas into the atmosphere) by
a certified mechanic using approved R-12 Recovery equipment. Many installers
will do this without charge, because the R-12 they recover from your system
is valuable.
2. Install the ADAPTERS onto the Service Ports (High Side & Low Side).
3 & 4. Add 1 can of R-134a refrigerant first, so the compressor is not
running “dry”.
Add the ESTER OIL that is included with the kit. Then add the remaining
R-134a REFRIGERANT, to a total of 80-85% of the original R-12 capacity.
5. Fill out and affix the LABEL to the engine.

Why does Interdynamics use Ester Oil instead of PAG Oil?

While both lubricants are used with R-134a, Ester is believed to be better
for Retrofit systems because they are much less hygroscopic, which means
that they don't absorb as much water from the atmosphere as PAG Oils do.
This moisture can create problems in a vehicle's A/C system. Ester is also a
truly Universal lubricant which has a Single Viscosity. PAG Oils come in a
variety of viscosities which must be matched to the vehicle. GM vehicles use
a high viscosity (150) PAG Oil, and non-GM vehicles use a low viscosity (46)
PAG Oil. You cannot use a 100 viscosity PAG Oil as a "1 size fits all"
universal lubricant. Ester Oil, however, is truly universal and will
lubricate properly regardless of viscosity.

What about the old oil left in the system? Don't you have to drain that?

No. The mineral oil left behind will not mix with the R-134a refrigerant.
That is why we add Ester Oil, because it will mix with R-134a and lubricate
the system components. The mineral oil just finds a low place in the system,
where it stays, until it is removed at some later date during future
maintenance or repair. The mineral oil does no good, but it does no harm.
It's just there.
How much R-134a do you use to fill a system?

You fill a system with 80-85% of the original R-12 Volume. Since there are 3
oz. of R-134a used as a propellant in the Oil provided in the kit, three 12
oz. cans of R-134a should be sufficient. The amount of R-12 Refrigerant in
the system can be found in the service manual or on a service plate located
in the engine compartment of the vehicle.

-----Original Message-----
From: v8-bounces+jgoldberg=ntelos.net at audifans.com
[mailto:v8-bounces+jgoldberg=ntelos.net at audifans.com]On Behalf Of Scott
Sent: Tuesday, June 28, 2005 4:17 PM
To: V8 at audifans.com
Subject: Re: [V8] Tools for A/C work

I would avoid any R12 alternatives as many aren't fully tested, aren't
goverment approved, and difficult to come by locally. Many are blends of
refrigerants, which tend to seep out of the system at different rates. A
R134A conversion can be as simple as replacing the oil with R134A oil, and
change the drier. Type 44 driers can be had for 25 bucks.


> Local pricing on R-12 refills is about $250.  R-134A conversions run in
> that same price range.  I'd like to try the alternative R-12 stuff like
> enviro-safe-12   ( http://autorefrigerants.com/co00033.htm ).  I presume I
> need a vacuum pump to get rid of moisture.  I have plenty of air
> compressor
> capability and was looking at the cheap air/vacuum pumps.  And I presume I
> need a gauge set too.   Do I need anything else to do this job right?
> My
> 200q20v needs recharging, I believe.  I think I need the gauges to check
> that the R12 has disappeared???    My two V8s also have old R12 systems.
> They work well now, but so has the 200 in the past.

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