GMC 4000 Series Service Manual page 310

DAMPER
CENTER PLUG
Figure 11 — Tool Application for Rem oving Crankshaft Dam per
d. Finally, check all bolts in proper sequence
to assure a minimum torque of 130 foot-pounds.
DO NOT LOOSEN ANY BOLT A SECOND TIME.
NOTE: No retorquing of head bolts is required
after engine warm-up.
7. Position water outlet hose at front of head
and install hose clamps.
8. Using new manifold gasket, install intake
and exhaust manifold on cylinder head. Tighten
manifold end bolts with washers (fig. 8) to 20 foot­
pounds. Tighten clamp bolts to 20 to 25 foot-pounds.
NOTE: Intake manifold openings should be
plugged or covered while installing on engine or
performing other work to prevent foreign objects
from falling into manifold openings.
9. Install push rods and assem ble rocker arm
and shaft assembly to cylinder head, refer to
rocker arm replacement procedure given previ­
ously under "In-Vehicle Component Replacement"
for instructions on installing rocker arms and
shaft, and rocker arm cover.
10. Referring to ENGINE FUEL SYSTEM (SEC.
6M) of this manual, install fuel injection nozzles,
leak-off lines, fuel high pressure lines, and fuel
injection pump controls. Instructions and illustra­
tions for installing fuel lines are included in ap­
propriate portion of ENGINE FUEL SYSTEM (SEC.
6M) of this manual.
11. Connect exhaust pipe to manifold.
12. After installing right-hand cylinder head,
mount fuel secondary filter assembly and connect
fuel supply line.
13. Assem ble air intake hoses and air cleaner.
14. On tilt cab models, install control island.
15. Fill cooling system and check for leaks.
Run engine until normal operating temperature is
reached, then recheck and adjust valve lash.
CRANKSHAFT DAMPER
REPLACEMENT
On some models, it may be necessary to re-
G M C S E R V I C E M A N U A L
PULLER SCREW
TORO-FLOW DIESEL ENGINE
1 Seal "O" Ring
2 Slinger
3 Key
4 Installer
5 Installer Screw
Figure 12— Installing Crankshaft Dam per
move radiator core to provide sufficient space for
a ccess to and removal of damper.
REMOVAL
NOTE: On some engines fan is mounted on hub
at front end of crankshaft. Remove hub mounting
bolts and remove fan mounting hub; then proceed
to remove pulley and damper as directed below:
1. Remove pulley which is bolted to damper
hub.
2. Remove bolt and retainer washer which
secures damper hub to crankshaft.
3. Assem ble puller (J-7879-01) in manner
shown in figure 11 and remove damper from crank­
shaft. A center plug is used at end of crankshaft to
serve as bearing for puller screw.
4. Remove O-ring seal, found either at coun­
terbore in damper hub, or on crankshaft behind key.
INSTALLATION
Key numbers in text refer to figure 12.
1. P lace new seal O-ring (1) on crankshaft and
position squarely at inner end of damper key (3)
as shown in figure 12. DO NOT PLACE SEAL RING
(1) AGAINST SLINGER (2). The seal ring must roll
into hub counterbore when damper is installed.
2. Apply engine oil on damper hub at surface
contacted by oil seal (10). Start damper onto crank­
shaft with keyway aligned with key (3). If damper
does not slide onto crankshaft easily, installer
screw (5) may be threaded into end of crankshaft
and installer (4) and thrust bearing (6) maybe used
to install damper.
3. Referring to figure 13, install cone, re­
tainer washer, and bolt as shown. Tighten damper
retainer bolt to torque shown on page 302.
Sec. 6B
Page 299
Thrust Bearing
6
7 Crankshaft Damper
Crankshaft
8
9 Engine Front Cover
10 Oil Seal ;
1 2 1 7