Operation Manual

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6. Reinstall filter.
NOTE: Replace filter if frayed, torn, damaged or unable to be cleaned.
Fig.11A Fig.11B
9.2 CUTTING BLADE
CAUTION: Be sure to disconnect and ground the spark plug wire before working on the cutting blade to
prevent accidental engine starting. Protect hands by using heavy gloves or a rag to grasp the cutting blades.
Tip mower as specified in separate engine manual. Remove the hex bolt and washer which hold the blade and
blade adapter to the engine crankshaft. Remove the blade and adapter from the crankshaft.
WARNING: Periodically inspect the blade adapter for cracks, especially if you strike a foreign object,
replace when necessary.
For best results your blade should be sharp. The blade may be re-sharpened by removing it and either grinding
or filing the cutting edge keeping as close to the original bevel as possible. It is extremely important that each
cutting edge receives an equal amount of grinding to prevent an unbalanced blade. Improper blade balance
will result in excessive vibration causing eventual damage to the engine and mower. Be sure to carefully
balance blade after sharpening. The blade can be tested for balance by balancing it on a round shaft
screwdriver. Remove metal from the heavier side until it balances evenly.
Before reassembling the blade and the blade adapter to the unit, lubricate the engine crankshaft and the inner
surface of the blade adapter with light oil. Install the blade adapter on the crankshaft. Refer to figure 12. Place
the blade with the part number facing away from the adapter. Align the washer over the blade and insert the
hex bolt. Tighten the hex bolt to the torque listed below:
Fig.12
9.3 BLADE MOUNTING TORQUE
Center Bolt 40Nm.min, 54Nm.max. To insure safe operation of your unit. ALL nuts and bolts must be checked
periodically for correct tightness. After prolonged use, especially in sandy soil conditions, the blade will
become worn and lose some of the original shape. Cutting efficiently will be reduced and the blade should be
replaced. Replace with an approved factory replacement blade only. Possible damage resulting from blade
unbalance condition is not the responsibility of the manufacturer.
When you change the blade, you must use the original type marked on the blade (Cobra Part No.
26300100401 contact your local dealer)