Briggs & Stratton 150Z Series Lawn Mower User Manual


 
20
CHECK / ADJUST PTO CLUTCH
Service Interval: 200 Hours.
The Power Take Off (PTO) clutch drives the mower
blades. The PTO clutch is engaged and disengaged by
the mower blade switch. Check the PTO clutch
adjustment every 200 hours of operation. Also perform
the following procedure if the clutch is slipping, will not
engage, or if a new clutch has been installed.
1. Remove key from ignition switch and disconnect
spark plug wires to prevent the possibility of
accidental starting while the PTO is being adjusted.
2. See Figure 24. Note the position of the 3 adjustment
windows (A) in the side of the brake plate and the
nylock adjustment nuts (B).
3. Insert a .012”-.015” (2,5-4mm) feeler gauge (C)
through each window, positioning the gauge between
the rotor face and the armature face as shown in
Figure 25.
4. Alternately tighten the adjustment nuts (B, Figure 24)
until the rotor face and armature face just contacts
the gauge.
5. Check the windows for an equal amount of tension
when the gauge is inserted and removed, and make
any necessary adjustments by tightening or
loosening the adjustment nuts.
NOTE: The actual air gap between the rotor and
armature may vary even after performing the adjustment
procedure. This is due to dimensional variations on
component parts, and is an acceptable condition.
6. Check the mower blade stopping time. The mower
blades and mower drive belt should come to a
complete stop within five seconds after the electric
PTO switch is turned off. If adjustment does not stop
a mower braking problem, replace the electric PTO
clutch.
Figure 24. PTO Clutch Adjustment
A. Adjustment Window (Qty. 3, one shown)
B. Adjustment Nut
A
B
B
B
A
B
C
Figure 25. Adjust PTO Clutch
A. Window
B. Adjustment Nut
C. Feeler Gauge
WARNING
To avoid serious injury, perform adjustments only
with engine stopped, key removed and tractor on
level ground.