Yamaha MM700A Manual page 121

a. Tape a piece of 400-600 grit wet emery paper onto a
piece of plate glass or a surface plate.
b. Move the case half slowly in figure-eight patterns
on the sandpaper. See Figure 55, typical.
surface is flat.
d. Rotate the case half several times to avoid removing
too much material from one spot.
3. Check the bearing support area (Figure 56) of both the
upper and lower halves.
4. Check the threaded holes in both crankcase halves for
damage or dirt buildup. If necessary, clean or repair the
with kerosene or aluminum tap fluid before use.
5. Check the studs in the upper crankcase for thread dam-
age. If necessary, replace damaged studs as described in
Chapter One.
6. Check the upper and lower crankcase halves around
the grooves for the oil seals and bearing retaining rings
(Figure 57 and Figure 58) for cracks or damage.
7. Inspect the seal and bearings for the coolant pump and
oil injection pump for wear or damage.
8. Check the machined surfaces of the coolant pump on
the lower crankcase half (Figure 59) for gouges or other
damage.
9. Inspect the coolant pump as described in Chapter
Eight.
case halves, and they cannot be repaired, replace the
crankcase halves as a set.
Crankshaft Inspection
Do not remove any bearings that are pressed onto the
crankshaft unless new bearings are available. Refer to
Figure 60 for an exploded view of a typical crankshaft.
1. Remove the crankshaft seals from each end of the
crankshaft. Replace the seals. Even though the seals may
be in good condition, replace them when the crankcase is
disassembled to make sure the crankcase is airtight when
it is assembled.
other damage.
3. Check the connecting rod small end side play by mea-
suring side-to-side movement with a dial indicator placed
against the small end (Figure 62). If the play exceeds the
service limit in Table 2 or Table 3, replace the big-end
bearing and connecting rod.
feeler gauge. Insert the gauge between the crankshaft and
the connecting rod as shown in Figure 63. If the side
61) and big end