Jeep 1996 Grand Cherokee Service Manual page 1156

ZJ
DIAGNOSIS AND TESTING (Continued)
(7) Check probe upper surface. If upper surface
is dry, converter and seal are OK. If probe upper sur-
face is wet, converter and/or seal is leaking.
(8) Fluid leaking under the probe is coming from
pump housing area. Leak could be from: pump seal
and/or bushing, pump vent, kickdown lever shaft
access plug, pump bolts, or porous spots in pump
body or transmission case (Fig. 17).
(9) If porous spots in the transmission case or
pump body are the suspected leak source, pressurize
transmission as described in Leak Testing With Air
Pressure.
Fig. 16 Leak Test Probe
Fig. 17 Pump Area Inspection Points
TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
(1) Leaks at the weld joint around the outside
diameter weld (Fig. 17).
(2) Leaks at the converter hub weld (Fig. 18).
LEAK TESTING WITH AIR PRESSURE
This test involves closing off all openings and pres-
surizing the transmission to 8 psi with hand oper-
ated Air Pump Tool 7700.
TRANSMISSION AND TRANSFER CASE
Fig. 18 Converter Leak Points—Typical
A soapy water solution is applied to suspected leak
points before and during the pressure test. Leaks will
be indicated by the presence of air bubbles coming
through the solution.
Some transmission openings such as the fill tube
and front cooler line fitting can be closed off with a
rubber plug or similar device. Plugs can secured with
wire or duct tape.
The transmission rear output shaft opening is
closed off simply by leaving the transfer case bolted
in place. However, if the transfer case has been
removed, a shipping plug can used to close off this
opening.
The torque converter hub opening in the pump and
the pump vent require special tools to close them off.
The converter hub seal cup is made from thin wall
tube and a 3.17 mm (1/8 in.) thick disc (Fig. 19).
A retaining strap is needed to secure the seal cup
for testing. The strap can be made from 31.75 mm
(1-1/4 in.) wide stock (Fig. 20). The strap attaching
hole positions are approximate only. Measure hole
position on the converter housing before drilling.
The pump vent tool is made from 6.35 mm (1/4 in.)
rod and 4.76 mm (3/16 in.) plate (Fig. 21).
The fabricated tools can all be made from mild
steel or aluminum stock.
Fig. 19 Converter Hub Seal Cup
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