Components; Reassembly Of Camshaft And Timing - Yanmar 4TNV98 Service Manual

Reassembly of Camshaft and Timing

Components

Installation of Gear Case or Front Plate
1. If removed, install a new camshaft bushing
(Figure 6-141, (3)) using the appropriate service
tool.
2. Apply a continuous bead of Three Bond Liquid
Gasket No. 1212 to the mounting area of the gear
case or front plate. Be sure to circle each bolt hole.
3. Install two new O-rings (Figure 6-141, (2)) in the
cylinder block.
Figure 6-141
4. Reinstall the gear case (Figure 6-141, (1)) Tighten
the bolts to the specified torque.
Installation of Camshaft
NOTE : The gear housing or front plate must be
reinstalled prior to installing the camshaft. See
Installation of Gear Case or Front Plate on page 136.
1. If removed, reinstall the camshaft end plate
(Figure 6-143, (1)), key, and timing gear (Figure
6-143, (4)) onto the camshaft using a press.
NOTE : Heat the gear to 356 - 392°F (180 - 200°C)
and press onto the end of the camshaft.
4TNV98 & 4TNE98 Diesel Engine
2. Rotate the cylinder block so that gravity will keep
the tappets (Figure 6-143, (5)) in place and out of
the way of the camshaft lobes when the camshaft
is being reinstalled.
NOTE : If the engine is not installed on an engine
repair fixture, stand the engine upright on the
flywheel end mounting flange.
NOTE : The tappets are "mushroom" shaped and
must be installed from inside the engine crankcase.
3. Lubricate the tappets with clean oil or assembly
lube. Reinstall the tappets in their respective
locations in the cylinder block. Push the tappets
fully into the tappet bores so they will not interfere
with the installation of the camshaft.
4. Lubricate the camshaft (Figure 6-143, (2)) with
clean engine oil or assembly lube. Slowly insert
the camshaft through the front of the engine.
5. Reinstall and tighten the cap screws (Figure 6-
143, (3)).
6. If removed, reinstall the fuel injection pump.
Adjust the fuel injection timing the engine after
installation. See Adjusting Fuel Injection Timing on
page 161.
Installation of Timing Gears
1. Set the No. 1 piston to top dead center.
2. Rotate the camshaft until the mark (Figure 6-144,
(C)) is approximately at the 9 o'clock position.
136
Figure 6-143
Section 3. Engine