MBW MM120 - Manual (Page 12)

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Lubrication
1. Grease both trunnions and pillow blocks daily. There
are two grease fittings on each side of the drum.
2. Oil clutch yoke shaft every 50 hours at the pivot
points (see Figures 1 & 2).
Checking Gearbox Oil
1. Remove check plug on side of gearbox.
2. Oil level should be even with bottom of check plug.
3. If low, add oil by removing the breather plug on top of
gearbox. Change oil if it appears dark brown or
smells burnt. Gearbox is shipped with 32 oz. of
Chevron 680 (140-wt.) worm gear oil. Any 90-wt., or
heavier, gear oil is acceptable for this gearbox. Do
not mix different types of oil.
4. Apply pipe sealant to check plug and breather plug
and reinstall them.
Changing Gearbox Oil
1. Remove breather plug on top of gearbox.
2. Remove magnetic drain plug on bottom of gearbox
and drain oil into pan.
3. Clean drain plug thoroughly.
4. Apply pipe sealant to drain plug and reinstall.
5. Add 32 oz. of gear oil. Chevron 680 (140-wt.) worm
gear oil is recommended, however any 90-wt., or
heavier, gear oil is acceptable.
6. Apply pipe sealant to breather plug and reinstall.
Adjusting Clutch
If clutch begins to slip, or if a positive snap is not felt when
engaging or disengaging clutch, the clutch should be
adjusted. Failure to do so could result in premature clutch
failure. The following procedure is easier if shroud is
removed (see Engine Shroud Removal, page 11).
1. Move engagement handle to “IDLE” position.
2. Stop engine and disconnect spark plug wire. Allow
gearbox and clutch to cool before continuing.
3. Remove the access cover which is secured with four
bolts.
4. Using the recoil starter, rotate the clutch so the
locking tab and bolt are facing up. Loosen bolt.
5. Hold the clutch body from rotating, and turn the
adjusting plate clockwise to increase the pressure on
the clutch disk. NOTE: It is easiest to use a flat
screwdriver against the teeth on the adjusting plate to
rotate it. Rotate the plate a small amount and check
it by engaging the mixer. If a positive snap is not felt,
rotate the plate further. If excessive force is required
to engage it, or if it does not engage, rotate the
adjusting plate counter-clockwise to decrease the
pressure.
6. Retighten the locking tab onto the teeth to hold the
adjusting plate in place.
7. Using a sprayable grease, lubricate all linkages and
moving parts of the clutch to increase the life of the
clutch.
8. Reinstall the access cover and tighten all four bolts.
9. Reconnect spark plug wire and start engine. Check
that a positive snap is still felt while running.
FIGURE 1
CHECK PLUG
BREATHER /
FILL PLUG
OIL PIVOT
FIGURE 2
DRAIN PLUG
OIL PIVOT
LOCKING TAB
ADJUSTING PLATE
DECREASE
PRESSURE INCREASE
PRESSURE
FIGURE 3