Yanmar 4BY, Service Manual

Page: 108 / 275

ENGINE
BY Service Manual 5-53
Camshaft and Timing Gear Train
5. Remove high-pressure pump sprocket using
special tool OEM No. 13 5 191. See Replacing
High-Pressure Fuel Pump on page 6-20.
6. Remove sprockets and timing chains.
7. Install lower chain on sprockets and install as
an assembly.
8. Install nut (Figure 5-84, (2)) and tighten to
65 N·m (48 ft-lb).
9. Install tensioner rail and guide rail. Remove
retainer (Figure 5-84, (1)) .
10. Install timing case cover. See Installing Timing
Case Cover on page 5-53 .
Installing Timing Case Cover
Note: The front crankshaft seal must be
installed with the timing case cover
installed.
1. Thoroughly clean all old gasket material from
mating surfaces.
2. Check condition and location of alignment
dowel sleeves.
Note: Only a one-piece gasket is available for
timing case cover and water pump.
When repairing timing chain cover only,
detach seal at marked points.
Figure 5-85
3. If coolant pump was not removed, cut gasket at
three locations (Figure 5-85, (1)) . Install gasket
(Figure 5-85) and apply a thin coat of Three
Bond 1207F (Yanmar part No. 977770-1207F)
sealing agent to gasket at ends (arrow) on both
sides.
4. Install timing case cover.
5. Install all bolts and tighten to an initial torque of
5 N·m (44 in.-lb), then tighten in an alternating
sequence to final torque specification of 14 N·m
(124 in.-lb).
6. After all bolts have been tightened to final
specification, tighten them a second time.
7. Install front crankshaft seal. See Replacing
Front Crankshaft Seal on page 5-68.
8. Install vibration dampener. See Removing and
Installing Vibration Damper - 4BY on page 5-50
or Removing and Installing Vibration Damper -
6BY on page 5-51.
9. Install alternator belt tensioner.
10. Install cylinder head. See Installation of
Cylinder Head on page 5-32.
11. Install oil sump. See Remove and Install Oil
Sump on page 8-16.
12. 4BY: Install alternator. See Remove and Install
Alternator on page 11-7.
13. Install alternator belt and belt guard. See
Remove and Install Alternator on page 11-7
and Replace Seawater Pump Belt on
page 7-21.
14. Fill engine with coolant. See Draining and
Filling Closed Cooling System on page 7-12.
15. Connect battery negative (-) cable.