air conditioner compressor

PLEASE HELP!!
I need to charge my air conditioning system but the compressor is
not running which is necessary for the charging process.
I charged it once this spring and it worked very well. But I
didn't put any dye in it to help find a leak, so of course it
eventually leaked out and now needs more freon r134a. This time I was
going to put the dye in but I'm stuck because the compressor is not
running. I'm pretty sure it's cause the low pressure switch is not
allowing it to run. In my Haynes book it says that this is not uncommon
and is easily taken care of by unplugging the low pressure wire plug
and jumping the wires and the compressor will run continuously allowing
me to fill with freon. The ONLY trouble with this whole thing is that
they don't show me where and what this plug looks like. The last thing
I want to do is start crossing wires and short something out.
If anyone can help I would greatly appreciate it.
Thank You,
Wirespool

 

Low pressure is between the expansion device and the suction hose
connection at the compressor. Look on or near the accumulator. Near
where you are adding freon.

 

black cap with a "L" on it

 

No, not necessary.

The purpose of the low pressure switch is to keep from burning up
the compressor due to lack of lubrication. You really sure you
want to defeat this?
Also; after multiple leaks, are you giving any thought to
evacuating the system, i.e., a deep vacuum to remove moisture or
how much oil is in the system?

Your lack of understanding WRT proper service procedures is apt
to create numerous problems/failures.

 

Not really, but go ahead.

Refrigerant containing "dye" is for lamers. It causes more problems
than it solves, including hose and seal deterioration, gumming up of
Schraeder valves, plugged expansion valves and on and on. Don't use
"dye" refrigerant. Poop Boys sells and promotes that crap, I believe,
so they can sell more compressor swap jobs out in the shop. The only
way to do a good leak test is with a proper halide detector. Small
leaks may need application of dry nitrogen to boost system pressure to
find them.

First, you don't say what car/system this is, so I'll assume it to be
a Chrysler H-block layout. If so, the low cutout switch is on the
H-block itself, a rubber 2 conductor plug...NOT the evaporator
thermostat, which is downstream on the suction side.

First, you obviously have a leaking system, and you're probably
already short of oil. Second, since the compressor's already cycling
due to vacuum on the suction side, there's a better than 50/50 chance
the system is contaminated with air and moisture, which is death to
any refrigeration system.

Take the car to a licensed tech and do it right the first time. I've
seen dozens of compressor failures/contaminated systems from people
getting those infernal "cans" at Poop Boys or similar and a cheapie
charging hose. Since 134A doesn't have the same oil miscibility as
12, oil level in the system in crucial to compressor survival. Second
in line is owners who add the wrong viscosity oil, or the wrong base
stock. Want to see a compressor fly apart? Just put some mineral
base stock refrigeration oil in a 134A system! If you do not have a
good vacuum pump that'll pull at least 100 torr, you can't do a good
job of purging/charging a system anyway.

Don't goof around...take it to a good shop, or your repair bill will
get larger as time goes on..

 

most systems will NOT run the compressor unless there is at least one
can of freon in the system- the clutch will not engage. It's a safety
feature to protect the compressor- it will usually start running after
you put the first can in- it will click on itself.

 

DESERTBOB aka OLDECHRYSLER (not its real name) is a troll.
It regularly frequents at least twenty news groups,
including many rabid/sex/racist groups.
Normally, it starts off with reasonable, even witty lines,
but rapidly drifts into lies, abuse and stupidity.
Check its details at Google Groups at this URLs- it has recently been
"branded" as a troll with its previous username, and has just created a

new Google Groups name to post here as "OldeChrysler"- read its post
history at these links for an eye-opening expose'- if you look at the
email addresses for each of its names, epiphany will strike:

http://groups.google.com/groups/pro...ADKWt-YFW4KG3QbhQogR222h-kUg4S0n7nbF1Te82ZIng

http://groups.google.com/groups/pro...AAf1goyQutX1XvM4SoVDe462TtJSBA4fw84ImzlcMxDpg

To see this troll's true nature, you can see its recent posts as
"DeserTBob" on alt.collecting.8track tapes, where is has clogged the
group with useless posts- effectively ruining the newsgroup, URL below:

http://groups.google.com/group/alt.collecting.8-track-tapes

It is a sad creature, deserving of pity, not anger.
Any direct response simply feeds it,
but it will go away if you ignore it.

 

Kill file list:





.....and a couple of others of which he's probably forgotten the
passwords. Most of his other Google troll accounts have already been
shut down.

 

Cite?
Many OEMs install system dye at the factory.

You're confusing dye with sealant and O-ring conditioner.

Actually, R-22 and pressurizing to 75psi or so with Nitrogen
works quite well and is 100% acceptable with the EPA.

100 torr? You're kidding right?
100 torr is a little less than 100,000 microns. If my vacuum
pump was only capable of 100,000 microns, I'd toss it in the
trash! A good vacuum pump is easily capable of <100 microns.

 

Experience, for one. Back when Du Pont came out with a "leak finding"
dye, service bulletins started flying around in the refrigeration
industry about these problems. Another big drawback is that is dyes
the oil, so you can't do a visual quality check, as well as makes a
general mess of the machine inside. There are some cites about this
in a couple of auto AC forums, but I'll have to dig them up again.

It's quite possible that newer dyes don't have the problems of the old
stuff that was used in halide refrigerants before 134A, but I've never
used them, having been warned off years ago.

Yes, it is, and since the 22 molecule is smaller, it makes small leaks
for 12 easier to find at lower pressures. A good trick to use for
those "half pound a year" cars.

No, I don't proofread! My mistake. Any reasonable AC service pump
should get down to <100 microns easily. A hi-vac like an old Kinney
(my favorite) will do a lot better, but then you start boiling off
volatiles out of the oil if you pull it down much below 20 microns for
awhile. With hi-vac hose and fittings, the old Kinneys would be able
to pull as low as 5 microns or less, depending on the volume of the
enclosed system. Most standard guage sets (the 4 valve
Imperial-Eastman's an exception) won't hold that low a vacuum, and
neither will the hoses attached to them.

For portable use, I have an old Sargent-Welch, which years later was
reincarnated into the ubiquitous Yellow Jacket pump seen everywhere.
It's good for 20 microns at blank-off, and my thermocouple usually
sees 30 on a barrier hose car AC system...for awhile, anyway. Pulling
a good vacuum is probably one of the most neglected aspects to car AC
service that I'd seen. Many still believe in the old "well, the
compound guage says 30"....must be done!" routine.

 

AAR: "OldeChrysler" is "DeserTBob"- he is a RICER that is posing as a
vintage car buff- that's why he's so far off on everything- his "air
bubbles in radiator/overheating problem" was in fact a friggin' STUCK
THERMOSTAT, that was stuck closed. He BS'd his way out of it saying
it was the water pump. He tore the entire top end off and pulled the
pan, when in fact it was a $10 part that takes 10 minutes to change at
best.

You make the call. Read the pro-ricer links in the other threads here,
that he posted on other sites.

 

....kicking your ass.

Kill file list:





.....and a couple of others of which he's probably forgotten the
passwords. Most of his other Google troll accounts have already been
shut down.