Before operating your chainsaw, ensure that it is fully and properly assembled. Turn the engine off and remove the spark plug cap from the spark plug before attempting to service your equipment. Wear heavy protective gloves while working with the chains on your equipment, especially while working with chains and bars.

The following instructions are based on the DCS6400, DCS6401, DCS6420, DCS6421, DCS7300, DCS7301, DCS7900, and DCS7901 model Makita chainsaws. Always read and be familiar with your equipment's operator's manual to understand the specific parts and procedures that pertain to your equipment.

• Step 1: Before mounting a new chain on your saw, check to see if the sprockets are excessively worn or damaged. Replace any sprockets that have the potential to damage the new chain.
• Step 2: Take off the sprocket guard.
• Step 3: Remove the chain and guide bar from the saw.
• Step 4: Remove the circlip. Hold it down with your thumb while you carefully remove it so that it doesn't jump out.
• Step 5: Remove the thrust washers.
• Step 6: Replace the sprocket guard with a new one.
• Step 7: Assemble the sprocket, thrust washers, and circlip.
• Step 8: Mount the new saw chain/guide bar.

For information about safety, warranty, and your specific model, read and be familiar with your owner’s manual.

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Before operating your chainsaw, ensure that it is fully and properly assembled. Turn the engine off and remove the spark plug cap from the spark plug before attempting to service your equipment. Wear heavy protective gloves while working with the chains on your equipment, especially while working with chains and bars.

The following instructions are based on the DCS6400, DCS6401, DCS6420, DCS6421, DCS7300, DCS7301, DCS7900, and DCS7901 model Makita chainsaws. Always read and be familiar with your equipment's operator's manual to understand the specific parts and procedures that pertain to your equipment.

Mounting the Guide Bar and Saw Chain

• Step 1: Set your chainsaw on a flat surface.
• Step 2: Pull the hand guard to release the chain brake.
• Step 3: Unscrew the retaining nuts on the lower right side of the power head.
• Step 4: Remove the sprocket guard.
• Step 5: Place the guide bar against the sprocket and the bolts through the slit on the guide bar.
• Step 6: Place the chain on the sprocket and position the chain in the groove on top of the guide bar.
• Step 7: Pull the chain around the front of the guide bar so that it is wrapped around the nose of the guide bar.
• Step 8: Guide the chain so that it goes over the chain catcher at the bottom of the guide bar.
• Step 9: If you need to remove slack in the chain, gently move the guide bar to the right to pull slack out of the chain.
• Step 10: Line up the holes and tensioning screw on the sprocket guard with the bolts and bottom hole on the guide bar.
• Step 11: Attach the sprocket guard and tighten the nuts.

Tightening the Saw Chain

• Step 1: Slightly loosen the retaining nuts on the bolts that connect the sprocket guard and guide bar.
• Step 2: Lift the guide bar up slightly.
• Step 3: Turn the chain adjusting screw on the sprocket guard clockwise until the chain is tight against the bottom of the guide bar.
• Step 4: Tighten the retaining nuts using a universal wrench while you still have the guide bar lifted.

For information about safety, warranty, and your specific model, read and be familiar with your owner’s manual.

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When servicing your starter cable and return spring, be aware of the possibility of springs/cables snapping and popping out. Always securely hold parts that are capable of moving as you work with them. Be careful while working with parts that are under tension.

The following instructions are based on the DCS6400, DCS6401, DCS6420, DCS6421, DCS7300, DCS7301, DCS7900, and DCS7901 model Makita chainsaws. Always read and be familiar with your equipment's operator's manual to understand the specific parts and procedures that pertain to your equipment.

Turn off your equipment's engine and allow it to cool before servicing it.

Replacing the Starter Cable

• Step 1: Unscrew the three screws that are securing the fan housing in place.
• Step 2: Remove the fan housing.
• Step 3: De-tension the cable drum return spring if you are replacing a starter cable that is not broken. To do this, pull the cable all the way out of the fan housing. Hold the drum with one hand while you place the cable in place. Allow the drum to turn until the return spring no longer has tension.
• Step 4: Remove the cable drum by removing the screw and washer securing it.
• Step 5: Take out any pieces of cable that remain.
• Step 6: Thread a new 1/8'' diameter, 38.6'' length cable. Ensure that the washer is included and that each end is knotted.
• Step 7: Pull the knot closest to the cable drum into the cable drum.
• Step 8: Pull the knot closest to the starter grip into the starter grip.
• Step 9: Place the drum on the spindle.
• Step 10: Slightly turn the drum on the spindle until the spring engages.
• Step 11: Screw in the screw and washer. Tighten.
• Step 12: Guide the cable into the drum. Use the cable to turn the drum clockwise twice.
• Step 13: Hold the drum with your left hand and untwist the cable with your right hand. Pull it tightly and hold it.
• Step 14: Release the cable drum carefully.
• Step 15: Repeat this three or four times. The grip should now be upright on the fan housing.

For information about safety, warranty, and your specific model, read and be familiar with your owner’s manual.

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Maintain a clean and properly assembled saw to not only maximize your productivity, but to extend the overall lifespan of your equipment. Remember to never operate your chainsaw unless it is fully assembled.

The following instructions are based on the DCS6400, DCS6401, DCS6420, DCS6421, DCS7300, DCS7301, DCS7900, and DCS7901 model Makita chainsaws. Always read and be familiar with your equipment's operator's manual to understand the specific parts and procedures that pertain to your equipment.

Before servicing your equipment, turn the engine off and allow it to cool.

• Step 1: Take off the filter hood.
• Step 2: Remove the air filter.
• Step 3: Take the spark plug cap off and unscrew the spark plug to remove it.
• Step 4: Push in the decompression valve, activate the chain brake.
• Step 5: Push the cable cutout and the ignition cable out to the side.
• Step 6: Remove the two screws on the cover that are furthest to the back.
• Step 7: Remove the screws that are securing the handguard pivot and take off the bushing.
• Step 8: Remove the cover from the air intake guide.
• Step 9: Put on the air filter again and secure it.
• Step 10: Insert the spark plug. Tighten it.
• Step 11: Place the spark plug cap on and pull the decompression valve out.
• Step 12: Take off the fan housing and remove the air guide.
• Step 13: Clean out the entire inner area using a brush and/or compressed air. Be gentle with your cleaning and do not use force that could damage wires or fragile parts.
• Step 14: Clean between the cylinder ribs and fins. Remember to clean between the mounting plate and the cylinder itself.

For information about safety, warranty, and your specific model, read and be familiar with your owner’s manual.

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The following instructions are based on the DCS6400, DCS6401, DCS6420, DCS6421, DCS7300, DCS7301, DCS7900, and DCS7901 model Makita chainsaws. Always read and be familiar with your equipment's operator's manual to understand the specific parts and procedures that pertain to your equipment.

Never touch the spark plug or plug cap while the engine is running. Make sure you turn the engine off and allow it to cool before attempting to service your equipment in any way. Wear protective eye and hand gear while performing maintenance.

Only use an NGK BPMR7A spark plug for the models listed above.

• Step 1: Turn off the engine and allow it to cool before beginning to work on your equipment.
• Step 2: Take the filter cover off.
• Step 3: Remove the spark plug cap from the spark plug.
• Step 4: Use the combination wrench supplied with your unit to remove the spark plug.
• Step 5: Replace the spark plug if insulator or electrode is excessively worn or damaged. If the electrode is very dirty or covered in oil, the spark plug should be replaced.
• Step 6: Check to make sure the electrode gap is .020'' (0.5 mm).
• Step 7: Set your combination tool between the head and the cylinder but not in the spark plug hole. Make sure it is only touching the cylinder.
• Step 8: Attach the spark plug cap to the unscrewed spark plug.
• Step 9: Hold the plug with insulated pliers against the combination tool (away from the spark plug hole).
• Step 10: Switch the ignition switch and pull the starter cable briskly.
• Step 11: A spark will be visible near the electrode if there is proper functionality.

For information about safety, warranty, and your specific model, read and be familiar with your owner’s manual.

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