How to Maintain Chippers and Shredders

Chipper/shredders can perform an amazing amount of work but are subjected to high levels of mechanical stress during normal operation. Maintenance falls into two categories: engine-related and chipper/shredder related. Both types of maintenance can be completed as needed in under an hour by most homeowners. Follow an "interval of use" maintenance schedule, beginning with the most frequently performed items first.

Things You'll Need

• Socket set (SAE or metric, depending on manufacturer)
• Replacement spark plug (model specific)
• Spark plug wrench
• Replacement air cleaner (model specific)
• Engine oil (model specific)
• Plastic oil drain pan
• Light machine oil
• Allen wrench set

Instructions

1. Clean grass and accumulated debris away from engine and muffler prior to each use. Keep the control linkage clean and debris-free to prevent control switch malfunctions. Fill the gas tank with gas, and be sure the gas cap is secured tightly prior to each use. Check that the engine oil level is sufficient prior to each use.

2. Lubricate all moving parts with a light machine oil every eight hours of operation. The hopper assembly and discharge chute should be lubricated at the swivel pivot joints, then tested for full range of motion. The chute release rod as well as all control levers should lubricated and checked for smooth operation.

3. Replace the engine air filter every 25 hours of machine operation. Loosen the screw holding the air filter cover in place, then remove the cover. Pull the old air filter out and install a new air filter. Install the air filter cover and make sure the cover-retaining screw is tight.

4. Change the engine oil after every 50 hours of operation. Run the engine for three minutes, then shut it off. Remove the oil drain plug from the base of the engine and drain the oil into a plastic pan. Replace the drain plug and tighten securely. Refill the engine with new engine oil per manufacturer recommendations.

5. Remove the spark plug wire from the spark plug to prevent accidental starting. Replace (or sharpen) the chipper blades annually or every 100 hours of machine operation by first removing the chipper chute (held in place by several hex-head screws and washers). Remove or loosen the chipper chute support brace before pulling the chute from the machine. Rotate the now-visible impeller assembly until you see one of two or more chipper blades screwed to the impeller assembly. Remove the chipper blade by removing the two Allen-head screws that hold it in place. Rotate the impeller to remove the remaining blades in the same fashion. Install new chipper blades by following the reverse order of the blade-removal sequence.

6. Replace (or sharpen) the shredder blades annually or every 100 hours of machine operation by first removing the hopper assembly (held in place by several hex-head screws and washers). If not previously done, remove the spark plug wire from the spark plug to prevent accidental starting. Rotate the now-visible impeller assembly until you see the two retaining screws that hold the shredder blade to the impeller assembly. Remove the shredder blade by removing the two Allen-head screws that hold it in place. Install a new shredder blade. Follow the reverse order of the blade-removal sequence to reassemble the machine.

References

• Craftsman: Operator's Manual Chipper Shredder