GMC 1982 Light Duty Truck, Service Manual

Page: 989 / 1435

AUTOMATIC TRANSMISSIONS 7 A - 11
CLOSED-END POP RIVET
(USE ONLY A CLOSED-END
POP RIVET FOR THIS FIX)
(— —
A-
I I r
OPEN END POP RIVET
(DO NOT USE THIS TYPE)
(X
Z >
1 0 2 9 7 9
Fig. 7A-22--Pop Rivets
Torque C o n verter E valuation
The converter should only be replaced if one of the
following conditions exist:
1. E ither the front oil pum p cover or body are badly
scored, which results in cast iron grindings entering the
converter and thus, the oil circuit. This could be a result
of the drive gear w earing into the crescent, or down into
the pocket, or the outer gear w earing in the pocket or
som e o th e r condition such as a crack e d flexplate,
causing the drive lugs on the drive g ear to becom e badly
dam aged.
2. In tern al converter failure, such as the stator overrun
clutch not locking, th ru st bearing failure, etc. Such
fa ilu res a re also n o rm ally asso ciated w ith
11 alum inized " oil in the converter.
3. End play in the converter exceeds 1.27 mm (.0 5 0 ").
This m easurem ent cannot be estim ated, but m ust be
m ade w ith tool J - 2 1371.
4. Leaking externally, such as at the hub weld area. A
converter th a t has been in service and which did not
leak, very likely never will.
5. A scored, or otherw ise d am a g e d h u b , w hich could
cause a front seal failure or front pum p bushing failure.
6. A broken, dam aged, or even possibly a bad fitting
POP RIVET
1 0 2 9 0 9
converter pilot, which could cause th e converter to
either not fit into th e c ran k sh aft bore properly or not be
correctly aligned w ith the crankshaft.
7. T he converter has an unbalance w hich results in a
vibration th a t cannot be corrected. M ost such problem s
are m in im al an d m ost tim es can be c o rre c ted by
following C onverter V ibration Procedure.
A secondary
balance procedure is to balance flywheel. If th e original
balance weights have broken loose and the procedure
discussed does not c o rre c t th e co n d itio n , th e n th e
converter should be replaced.
The converter should not be replaced for
one of the
following conditions:
1. T he oil has an odor, is discolored, and th ere is no
evidence of m etal particles. T here is no indication th a t
there is internal dam age, nor any front pum p dam age.
D um p out as m uch oil as possible from the converter
and replace only the oil filter in the pan.
2. T h e oil cooler w as defectiv e w hich allow ed engine
coolant to e n te r th e tran sm issio n . D rill, d ra in an d
repair the converter as described in converter flushing
procedure. (Including T .C .C . C onverters).
3. A small am ount of w ear (som etim es referred to as
fretting w ear) appears on the hub w here th e oil pum p
drive gear locates. A certain am ount of such w ear is
norm al for both the hub and oil pum p gear. N e ith e r the
co n v erter nor th e fro n t pum p assem b ly should be
replaced.
4. T he threads in one or m ore of the th ree converter bolts
holes are dam aged. C orrect such conditions w ith the
use of a Heli-Coil or its equivalent.
GENERAL SERVICE PROCEDURES
Engine C oo lan t In Transmission
If the transm ission oil cooler, located in the rad iato r
assem bly, has developed a leak allowing engine coolant to
enter the transm ission, use the following procedure:
1. Remove transm ission from vehicle.
2. D isassem ble transm ission and replace all ru b b er type
seals. (T he coolant will a tta c k the seal m aterial causing
leakage.)
U S IN G TOOL J-21369, CHECK
CONVERTER FOR LEAKS AT 80 PSI
DETECTING S O LU TIO N TO POP RIVET
Fig. 7A-23--Pop Rivet Installed
Fig. 7A-24--Pressure Testing Converter