MACS Service Reports - 2015 - NOV4

the first time? Are all fittings sealing perfectly? The vehicle may have been working fine for a couple of years
since then. Some techs may say if it's not broke don't fix
it, while others may think of themselves more like physicians and their customers' vehicles as patients. In the latter scenario, a post-surgery check-up is in order with the
very minimum of an A/C system performance test. Since
pressures and temperatures are especially difficult to assess with variable displacement compressors, the use of a
J2788 RRR machine to recover and recharge becomes an
accurate test of the system's ability to hold a charge. The
J2788 RRR machine standard has been well documented
over the last few years via various MACS publications
and live training classes.

Delphi

refrigerant oil, which in turn leads to compressor death. See Figures 3, 4 & 5.

Figure 3: Compressor clutch slipping telltale signs (discolored points at
rivets) gives the PM inspection clue that a major failure may take place if
the root cause is not corrected.

Delphi

J2788 SAE Compliant RRR Machines (machines sold
after April 2008)
* The old SAE standard was J2210. Look on the
back of your machine for the standard you have.
* 95% recovery efficiency within 30 minutes,
meaning you get almost ALL the refrigerant out of
the system you are servicing.
* Charge accuracy within ½ ounce, meaning
those lower capacity systems are NOT going to be
overcharged / undercharged.
* Auto A/C system oil recovery meaning you are
going to be able to actually know how much oil
came out of that system you are servicing as opposed to guessing.
* A more user friendly method of calibrating
charge scale accuracy.
* Mandatory filter changes meaning you have to
keep your machine maintained or it locks you out.
* Automatic air purge meaning you are not going to have a problem putting air back into your
customer's systems.
* Newer standard achieves full system recovery
by mandating the vacuum pump achieving far
beyond the old standard.

Figure 4: This orifice tube indicates the vehicle's compressor is likely on the way
out. Future A/C checks should be promoted as follow up after the job is done.

Those four reasons all
line up for the potential
sale of a refrigerant recharge, depending on the
customer and the vehicle.
Even though this service
is not always OEM required, you could make it
Figure 5: The sealant in this coma recommended service in
pressor indicates a major repair.
at least some cases. If the
Could it have been caught with
customer has experienced
early detection that can come out
catastrophic A/C comof A/C preventative maintenance?
pressor damage accompanied by a hefty repair bill,
this should spark interest. Did you get all the debris out

Delphi

Note: As you look at PM on your customer's A/C
systems, don't forget the PM of your own equipment. For example, you can't expect to really get
the moisture that causes system performance and
long term corrosion / damage to be boiled out
of your system unless you maintain your RRR
machine's vacuum pump. Achieving as close to
the perfect vacuum as possible (30 inches of Hg at
sea level).

November 2015

MACS Service Reports

Table of Contents for the Digital Edition of MACS Service Reports - 2015