TRUCK SERVICE MANUAL
ENGINE
b. To set the depth of cut, place a feeler gauge of
1. Install ST-1084 Bore Adapter (8, Fig. 1-14) onto ST-
required thickness between adjusting nut and top of housing.
1081 Boring Tool.
For example: if 0.005 inch [0.13 mm] of material is to be
2. Install ST-1064 Adapter Plate (4) onto boring tool with
removed from counterbore ledge, use 0.005 inch [0.13 mm]
3/4 inch recess toward bore adapter.
feeler gauge. Make sure there is no grease or dirt between
3. Engage retaining nut (5) onto boring tool and tighten
adjusting nut and top of housing.
retaining nut until boring tool, bore adapter and adapter plate
c. Rotate adjusting nut until feeler gauge is just held
are secure.
between adjusting nut and top of housing. Tighten locking
4. Install ST-1081-52 Tool Holder (9) into boring tool (7)
screw. Remove feeler gauge.
and tighten in position with capscrews (10).
d. Hold down on handle applying more pressure on tool
PRESETTING TOOL BIT
bit side and rotate handle in a clockwise direction until unit
turns freely and is bottomed out between adjusting nut and top
1. Loosen two setscrews. Install ST-1081-55 Tool Bit
of housing.
into tool holder, being sure that spring is in place.
e. Measure depth of counterbore as described in Step 5.
2. Push in on tool bit until it bottoms on spring. Lock one
setscrew.
ST-1081 Boring Tool (Lower Cylinder Liner Bore)
3. Place tool holder into setting gauge and fasten in place
with capscrew finger tight and position point of tool bit so it will
ST-1064, ST-1081, ST-1081-52 and ST-1084 Service Tools
engage setting nib.
are also used in this operation. Assemble boring tool as
Note:
Proper nib will be indicated by stamped letters or
follows:
numerals for particular engine.
4. Loosen setscrews allowing point of tool bit to engage
setting nib, then tighten against bit.
5. Remove tool holder and bit from setting gauge. Install
in boring tool.
INSTALLATION AND OPERATION
1. Install assembled boring tool into cylinder block,
allowing bore adapter (8) to engage counterbore and holes in
adapter plate to match holes in cylinder block.
2. Fasten adapter plate in place, tighten capscrews to 50
to 75 ft-lbs [6.9 to 10.4 kg m] torque. Install torque reaction
bar (3) into plate.
3. Install gear drive (2) onto boring tool with 1/2 inch
square drive engaging boring tool and gear drive anchor arm
engaged over the torque reaction bar.
4. Install drive adapter (12) into drill motor (1)and fasten
in place. Engage adapter and motor onto gear drive.
5. Being sure boring tool shaft is in maximum up position,
turn on drill motor. Initial contact of tool bit with bore will be
intermittent and care should be exercised at start of cut. While
unit is rotating, apply a slight downward pressure until
maximum depth bf bore is complete.
1. Drill Motor
8. Bore Adapter
2. Drive Gear
9. Tool Holder
6. Pull-up on drive shaft of boring tool (turning clockwise)
3. Torque Reaction Bar
10. Capscrew
until drive shaft is in up position, then repeat procedure to be
4. Adapter Plate
11. Capscrew
sure of a true hole.
5. Retaining Nut
12. Drive Adapter
6. Retaining Nut Handle
13. Upper Bearing
7. Boring Tool
Fig. 1-14, (V40153), ST-1081 Tool Bit installed in blockST-
1081 Tool Bit installed in block
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