Toro T4240, Operator'S Manual

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Cutterhead Cylinder To Bottom Blade Adjustment
IMPORTANT: PREVENT DAMAGE - It is essential that the relationship between the bottom blades
and the cutting cylinders is kept in good adjustment in order to ensure good cutting performance,
minimum power consumption and prolonged life for the cutting edges.
Carry out the following procedure before commencing work and
re-check the settings every few hours.
Check that the cutting cylinder is correctly set to the bottom blade
by holding a thin piece of paper between the cutting cylinder and the
bottom blade as shown. Carefully rotate the cylinder as shown and
check that the paper is cut cleanly at all points along the length of the
blade. Hold the paper at 90̊ (right angles) to the bottom blade to
obtain the correct cutting action.
WARNING: PREVENT ACCIDENTS - Ensure that people are clear of the cutting cylinders as rotation
of one may cause others to rotate.
If adjustment is necessary proceed as follows;
Release nut ‘A’ 1/4 turn both ends.
Turn hand wheel ‘B’ each end alternately whilst rotating the cutting
cylinder backwards until the bottom blade is in ‘fleeting’ contact with
the cylinder along its entire length. Re-check the cutting action along
the length of the bottom blade using a thin piece of paper making
marginal adjustments as necessary.
Tighten nut ‘A’ both ends.
If it is impossible to obtain a good clean paper cut across the entire length of the bottom blade it will be nec -
essary to carry out the back lapping procedure to reprocess the cutting edges. In severe cases it will be neces -
sary to regrind the cutting cylinder and the bottom blade, refer to BACK LAPPING/GRINDING .
Do not be tempted to over adjust, thus causing heavy contact between the cylinder and bottom blade, as this
will cause very rapid uneven wear to take place leading to tram lining and waviness of the cutting edges. The
frictional losses will be high and a significant amount of power will be absorbed, thus
reducing the power available for cutting. The heating effect due to friction will cause excessive
expansion to take place which will further aggravate the situation by increasing the contact pressure.
If the cutterheads are allowed to operate for more than a few hours without adjustment the running wear will
eventually cause the cylinder to run out of contact with the bottom blade. At this stage very rapid rounding of
the cutting edges will occur as grass and abrasive particles pass through the clearance
between the blades.
Lack of attention to adjustment can therefore be foolhardy as maintenance costs will escalate. The
quality of cut will also be seriously affected as will the health and growth of the grass.
An experienced operator will notice when a cutterhead starts to go out of adjustment; when the grass ceases
to be cut cleanly and the cut ends become ragged.
MAINTENANCE
90
0
B
A