Dodge ram truck 3500 1996 Service Manual page 274

6 - 1 2 CLUTCH B R
D I A G N O S I S A N D T E S T I N G ( C o n t i n u e d )
Correcting Clutch Housing Bore Runout—NV4500 l a s
Engine Only
On gas engine vehicles, clutch housing bore runout
is corrected with offset dowels. However, i f bore
runout exceeds 0 . 0 1 5 in. TIR on a diesel equipped
model, the clutch housing, or transmission adapter
plate may have to be replaced. Offset dowels are not
available for diesel models.
The dial indicator reads positive when the plunger
moves inward (toward indicator) and negative when
it moves outward (away from indicator). As a result,
the lowest or most negative reading determines the
direction of housing bore offset (runout).
In the sample readings shown (Fig. 1 3 ) and in Step
7 above, the bore is offset toward the 0 . 0 1 0 inch
reading. To correct this, remove the housing and orig­
inal dowels. Then install the new offset dowels in the
direction needed to center the bore with the crank­
shaft centerline.
In the example, TIR was 0 . 0 1 2 inch. The dowels
needed for correction would have an offset of
0 . 0 0 7
in. (Fig.
1 3 ) .
INDICATOR
PLUNGER
DIAL INDICATOR
SLOT S H O W S DIRECTION
OF OFFSET
OFFSET
D O W E L
DOWEL SELECTION
mm
VALUE
OFFSET DOWEL
REQUIRED
0.011 - 0 . 0 2 1 inch 0 . 0 0 7 inch
0 . 0 2 2 - 0 . 0 3 5 inch
0 . 0 1 4 inch
0 . 0 3 6 - 0 . 0 5 2 inch 0.021 inch
J 9 2 0 6 - 7
Fig. 13 Housing Bore Alignment Dowel Selection
Install the dowels with the slotted side facing out
so they can be turned with a screwdriver. Then
install the housing, remount the dial indicator and
check bore runout again. Rotate the dowels until the
TIR is less than 0 . 0 1 0 in. i f necessary.
I f a TIR of
0 . 0 5 3
in. or greater is encountered, i t
may be necessary to replace the clutch housing.
Measuring Clutch Housing Face Runout—NV4500
( 1 ) Reposition the dial indicator plunger on the
housing face (Fig. 1 4 ) . Place the indicator plunger at
the rim of the housing bore as shown.
( 2 ) Rotate the crankshaft until the indicator
plunger is at the 1 0 O'clock position on the bore.
Then zero the dial indicator.
CLUTCH
HOUSING
FACE
INDICATOR MOUNTING
STUD OR ROD
J9006-29
Fig. 14 Measuring Clutch Housing Face Runout
( 3 ) Measure and record face runout at four points
9 0 ° apart around the housing face (Fig. 1 5 ) . Perform
the measurement at least twice for accuracy.
+ .009
CLUTCH
H O U S I N G
FACE
CIRCLE
(AT RIM
O F BORE)
.004
(SAMPLE READINGS)
J9006-30
Fig. 15 Housing Face Measurement Points And
Sample Readings
( 4 ) Subtract the lowest reading from the highest to
determine total runout. As an example, refer to the
sample readings shown (Fig. 17). I f the low reading
was minus
0 . 0 0 4
in. and the highest reading was
plus
0 . 0 0 9
in., total runout is actually
0 . 0 1 3
inch.
( 5 ) Total allowable face runout is 0 . 0 1 0 inch. I f
runout exceeds this figure, runout will have to be
corrected. Refer to Correcting Clutch Housing Face
Runout.
CORRECTING CLUTCH HOUSING FACE
RUNOUT—NV4500
Housing face runout, on gas or diesel engines, can
be corrected by installing shims between the clutch
housing and transmission (Fig. 16). The shims can be
made from shim stock or similar materials of the
required thickness.
As an example, assume that face runout is the
same as shown i n (Fig. 1 7 ) and in Step 4 . I n this