Leak Detectors - Pontiac FIREBIRD 1972 Service Manual

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1972 PONTIAC SERVICE MANUAL
Fig. 1A-1 J 6084 Leak Detector
TO CLEAN ORIFICE
1. Never attempt to clean orifice by passing anything
through the hole.
2. Unscrew burner assembly from burner tube by apply-
ing wrench to hexagon part located immediately be-
low search hose connection. Turn to left. This will
expose orifice block which is inserted into the end of
the tube.
3. Remove orifice block from tube.
4. Reverse orifice block and replace against burner tube;
screw burner head onto burner tube (hand tight),
then open valve quickly, admitting several short
blasts.
5. To reassemble: unscrew burner head, insert orifice
block into burner tube, and screw burner head onto
burner tube with a wrench to form a gas-tight joint.
CHECKING FOR REFRIGERANT LEAKS
After the leak detector flame is adjusted, check for refrig-
erant leaks in an area having a minimum amount of air
flow in the following manner:
Explore for leaks by moving the end of the search hose
around all connections and points where a leak may be.
Check around the bottom of connections, since refrigerant
is heavier than air and will, therefore, be more apparent
at the bottom of fittings.
The color of the flame will turn to a yellow-green when
a small leak is detected. Large leaks will be indicated by
a change in color to brilliant blue or purple. When the
suction hose is moved awav from the leak. the flame will
CORRECTION FOR YELLOW FLAME
If the flame is yellow, insufficient air is being aspirated or
the reaction plate is dirty. Insufficient air may be caused
by:
1. Obstructed or partially collapsed suction tube.
2. Dirt or foreign substance in burner tube.
3. Dirty or partially clogged orifice.
Blowing air through the suction tube and back through
the detector will usually clear dirt or foreign matter. If a
yellow flame is caused by a dirty reaction plate, allow the
flame to burn for several minutes. This will usually burn
the plate clean. If an oxide film appears on the reaction
plate from continued use, it will reduce the sensitivity of
the detector. This may be remedied by removing the plate
and scraping the surface gently with a knife.
clear to an almost colorless pale blue again.
WARNING: Do not breathe the fumes and black
smoke that are produced by a large leak. They are
poisonous. Any time an open flame is used near
a car there is a certain amount of danger. Al-
though the torch flame is small and well pro-
tected, it is recommended that a fire extinguisher
be close at hand for any emergency that might
arise.
LIQUID LEAK DETECTORS
There are a number of fittings and places throughout the
air conditioning unit where a liquid leak detector solution
may be used to pinpoint leaks.
By merely applying solution to the area with the swab that
is attached to the bottle cap, bubbles will form within
seconds if there is a leak.