BBM 25 Push Mower Model: BB25-Kawasaki. Manual - part 4

13

BLADE MAINTENANCE 

For best results, the mower blade must be kept sharp.  Always 
replace a bent or damaged blade.

Removing the blade 
1. Disconnect spark plug wire from spark plug and place wire
where it cannot come in contact with plug.
2. Turn lawn mower on its right side.  (Make sure air fi lter and
carburetor are up).
3. Use a wood block between blade and mower deck to
prevent blade from turning when removing blade bolts.
NOTE: Protect your hands with gloves and/or wrap the blade
with a heavy cloth.
4. Remove blade bolts by turning counter-clockwise with a
11/16” (17mm) wrench or socket.

Installing the blade

1. Position the blade with the bent corner of the blade (sail)
pointing towards the deck.  Install the blade bolts.

 Important:

Blade bolts are heat treated.  If a bolt is worn or

 damaged

replace it only with a bolt available from 

Bad Boy Mowers.

2. Use a block of wood between blade and mower deck and
tighten the blade bolts.  Always use a torque wrench.
The recommended tightening torque is 30 to 35 ft. lbs.
(40 to 45 Nm)

WARNING

Use only a replacement blade approved by 

Bad 

Boy Mowers.  Using a blade not approved by 

Bad Boy Mowers is hazardous.  It can damage 
your mower and cause serious personal injury.  

A worn or damaged blade can break and parts of 
the blade could be thrown into the operators or 
bystanders area, resulting in serious personal 
injury or death.

Inspecting the blade
Carefully examine the blade for straightness, damage and 
abnormal wear.  In some areas abrasive sand and dust can 
wear away the metal of the blade - see illustration.  

1. Cutting edge
2. Square corner
3. Erosion from sand and dirt
4. Air lift wing (sail)

1

2

3

4

1

2

3

4

1

3

4

MAINTENANCE

Sharpening the blade
File the top side of the blade (1) and maintain the original 
angle of the cutting edge.  Maintain the radius where the cut-
ting edge ends.  Always remove the same amount of material 
from both ends of the blade.  This ensures that the blade stays 
balanced.  

If sharpening is done with a grinding stone the blade should 
always be balanced using a blade balancing device.  A blade 
balance tool is available from 

Bad Boy Mowers or most lawn 

and garden dealers, and hardware stores. 

If the blade shows wear or cracking at the edge where the 
blade is bent up (3) it must immediately be replaced.  

ENGINE OIL CHANGE

NOTICE: Before tipping lawn mower on its right side to drain 
oil, empty fuel tank by running engine until fuel tank is empty.

1. Disconnect spark plug wire from spark plug and place wire
where it cannot come in contact with plug.

2. Remove oil fi ller cap/dipstick.

3. Tip lawn mower on its right side as shown and drain oil
into a suitable container.  Rock lawn mower back and forth to
remove any oil trapped inside of engine.

4. Wipe off any spilled oil from lawn mower or side of engine.

5. Fill engine with oil. Slowly pour oil down the oil fi ll spout
into the engine.  Use an SAE 10W-30 oil (22 Fl.Oz - 0.65 Liter
without oil fi lter, 29 Fl.Oz - 0.85 Liter with oil fi lter replacement).
See engine Owner’s Manual for complete information.

6. Wait one minute to allow oil to settle.  Use gauge on oil fi ller
cap/dipstick for checking level.  Insert dipstick into the tube
and rest the oil fi ll cap on the tube.
DO NOT thread the cap into the tube when taking the reading.

7. Continue adding small amounts of oil and rechecking
the dipstick until it reads full.  DO NOT overfi ll, or engine
will smoke on startup.

8. Always be sure to retighten oil fi ll cap/dipstick before
starting engine.

9. Reconnect spark plug wire to spark plug.