Riviera V6-231 3.8L Turbo VIN 8 4-bbl (1983)
Valve Body: Customer Interest
A/T - Apparent Loss of Engine Power
Model Year
1983
Bulletin No.
83-174
File in Group
70
Number
32
Date
Aug. '83
SUBJECT:
Apparent Loss of Engine Power
MODELS AFFECTED: 1982 & 1983 THM 325-4L Transmissions - All Models
Some 1982 and 1983 vehicles equipped with a THM 325-4L transmission may exhibit an apparent loss of engine power. This condition may be caused
by an incorrect application of the low and reverse clutch assembly, during third speed operation.
FIGURE 1
This condition is caused by a missing coiled spring pin that is used for locating the Lo-1st detent valve bushing in the control valve assembly. (Figure
#1). The absence of the coiled spring pin allows the Lo-1st detent valve bushing to rotate in its bore, allowing detent oil to apply the low and reverse
clutch.
When servicing any 1982 and 1983 THM 325-4L for this apparent loss of engine power condition, inspect the Lo-1st detent valve bushing for correct
orientation in its bore (Figure #1). If the bushing is found misoriented and the coiled spring is missing, reorientate the bushing in its bore and install a
coiled spring pin (Part #8628400).
