Chrysler RAM TRUCK 2500 1994 Service Manual page 253

6 - 20 CLUTCH
•
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
i t 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 i n Figure 24 and i n
step (7) above, the bore is offset toward the 0.010
inch reading. To correct this, remove the housing and
original dowels. Then install the new offset dowels i n
the direction needed to center the bore with the
crankshaft centerline.
In the example, TIR was 0.012 inch. The dowels
needed for correction would have an offset of 0.007
in. (Fig. 25).
Install the dowels with the slotted side facing out
so they can be turned with a screwdriver. Then i n ­
stall the housing, remount the dial indicator and
check bore runout again. Rotate the dowels until the
TIR is less than 0.010 in. i f necessary.
I f a TIR of 0.053 in. or greater is encountered, i t
may be necessary to replace the clutch housing.
7/16 - 20 THREAD
NUT
STUD O R THREADED ROD
/
•10 INCHES L O N G -
CLUTCH
H O U S I N G
BORE
CIRCLE
+ .004
(SAMPLE READINGS) J9Q06-27
Fig. 24 Housing Bore Measurement Points And
Sample Readings
SLOT SHOWS DIRECTION
OF OFFSET
DOWEL S
OFFSET
ELECTION
TIR
VALUE
OFFSET DOWEL
REQUIRED
0.011 - 0.021 inch 0.007 inch
0.022 - 0.035 inch
0.014 inch
0.036 - 0.052 inch
0.021 inch
J9206-7
J9O06-25
Fig. 22 Dial Indicator Mounting Stud Or Rod
MOUNTING STUD DIAL INDICATOR
INDICATOR
PLUNGER
CLUTCH
H O U S I N G
BORE J9006-26
Fig. 23 Checking Clutch Housing Bore Runout
Fig. 25 Housing Bore Alignment Dowel Selection
M E A S U R I N G CLUTCH HOUSING FACE
RUNOUT (NW4S00I
(1) Reposition the dial indicator plunger on the
housing face (Fig. 26). Place the indicator plunger at
the r i m of the housing bore as shown.
(2) Rotate the crankshaft until the indicator
plunger is at the 10 O'clock position on the bore.
Then zero the dial indicator.
(3) Measure and record face runout at four points
90° apart around the housing face (Fig. 27). Perform
the measurement at least twice for accuracy.
(4) Subtract the lowest reading from the highest to
determine total runout. As an example, refer to the
sample readings shown i n Figure 27. I f the low read­
ing was m i n u s 0.004 i n . and the highest reading was
plus 0.009 in., total runout is actually 0.013 inch.
(5) Total allowable face runout is 0.010 inch. I f
runout exceeds this figure, runout will have to be
corrected. Refer to Correcting Clutch Housing Face
Runout.