Bolens 979 Service Manual

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11
SECTION 6:  MAKING ADJUSTMENTS
WARNING: Do not at any time make any
adjustments without first stopping engine
and disconnecting spark plug wire.
Cutting Height Adjustment
Your mower is shipped with the cutting height in the 
lowest position. The cutting height adjustment lever is 
located above the left rear wheel. To adjust the cutting 
height, pull the lever out and away from the mower and 
then move it forward or backward to select a new 
cutting height. See Figure 10.
NOTE:  For rough or uneven lawns, move the height
adjustment lever to a higher position. This will help stop
scalping.
Figure 10
Handle Height Adjustment
Your mower is shipped with the handle in the higher 
height position. To lower the height proceed as follows:
Remove the starter rope from the rope guide.
Remove the upper handle by removing the hand 
knobs and carriage bolts. Lay the upper handle out 
of the way, being careful not to bend or kink the 
cables.
Remove the hairpin clips from the weld pins on the 
handle brackets and remove the wing nuts and 
carriage bolts from the upper hole on the handle 
mounting bracket.  Press out on the legs of the 
lower handle and remove lower handle from the 
mower.
Turn lower handle around so the notch on the 
bottom of the lower handle is facing forward.
See Figure 11.
Reassemble, placing the bottom holes in the 
handle over the weld pins in the handle mounting 
bracket.
Place the hairpin clips in the inner holes in the weld 
pins and  insert the carriage bolts the upper hole on 
the handle mounting bracket and secure with 
plastic wing nuts.
Reassemble the upper handle to the lower handle.
Attach the starter rope as instructed in the 
Assembly Section.
   
Figure 11
Drive Clutch Control Adjustment
The adjustment wheel is located in the drive clutch 
control handle housing and is used to tighten or loosen 
the drive belt. You will have to adjust the drive clutch 
control if any of the following happens:
The mower does not propel itself with the drive 
clutch engaged.
The mower’s drive wheels hesitate with the drive 
clutch engaged.
To resolve the above problems, rotate the adjustment 
wheel with your fingers. Clockwise to tighten the cable 
and counter-clockwise to loosen the cable.
See Figure 12.
Figure 12
NOTE:  For some people the drive clutch control may
not be in a comfortable position. You can adjust the
handle out by tightening the adjustment wheel.
Shift Lever Cable Adjustment
Periodic adjustment of the six speed shift cable may be 
Cutting Height
Adjustment Lever
Lower
Higher
Notch
Lower Handle
Adjustment
Bottom View
Wheel
Drive Clutch
Control
Upper
Handle