Yanmar 1GM User Manual page 125

MVLTlCYL INDER ENGINES
1. Disconnect the negative battery cable from the nega-
tive battery terminal.
2. Remove the alternator as described in Chapter Nine.
3. Remove the oil filter.
4. Detach the control cab les from the speed control lever
and the stop lever.
119
5. Remove the fuel injection pump as described in Chap-
ter Seven.
6. Remove the seawater pump as described in Chapter
Eight.
7. Remove the crankshaft pulley retaining nut. Using a
suitable puller, remove the crankshaft pulley (Fi gure 46,
typical). Remove the drive key from the crankshaft.
8. Remove the manual starter cover (Fi gure 47, typical).
9. Remove the setscrew in the end of the camshaft (A,
Figure 48 , typical), the n remove the manual starter drive
pin (B). . . . - -
10. Remove the timing gearcasc (Fi gure 49). 6
11 . Remove the gaske t and any residue from the gearease L _
and crankcase surfaces.
12. If cran kshaft or starter seal replacement is necessary,
proceed as follows:
a. Pry the old seal from the gearcase with a large
screwdriver. Work carefully to prevent damage to
the gearcasc seal surface.
b. C lean the seal recess in the cover with solvent and
blow it dry wit h compressed air.
c. Apply gasket sealer to the periphery of the seal.
d . Position a new seal in the cover recess with its open
end facing the inside of the gearcasc. Drive the seal
into place with a suitably sized seal driver or socket.
13. If crankshaft bea ring replacement is necessary, pro-
ceed as follows:
a. Refer to Chapter Seven and remove governor shaft
from timing gearcase.
b. Pry the sea l from the gearcase with a large screw-
driver. Work carefully to prevent damage to the
gearcasc seal sur face.
c. Drive or press out the bearing.
Force the bearing to-
ward the inside of the gcarcase.
d. Clean the seal and bea ring recesses in the cover
with solvent and blow them dry wit h compressed
air.
e. Drive or press in a new bearing until the bearing
scats in the recess in the gearcase.
f.
App ly gas ket sealer to the peri phery of the seal.
g. Position a new sea l in the cover recess wit h its open
end facing the inside of the gearcase. Drive the seal
into place with a suitably sized seal driver or socket.
h. Refer to Chapter Seven and reinstall the governor
shaft.
14. Reverse the removal procedure to reinstall the timing
gearcase. Refer to Table 4 for the tightening torque of the
gearcase retaining screws.