How to Adjust the Valves on the Kawasaki Mule 3010

Kawasaki produced the Mule 3010 utility vehicle between 2001 to 2008. Kawasaki fitted the Mule 3010 with a 617 cc, four-stroke V-twin engine and a continuously variable transmission mated to a four-wheel-drive, two-speed transfer case that allowed the Mule to travel over rough terrain with ease. As part of a regular maintenance schedule, Kawasaki recommends an inspection and adjustment of the engine's valve clearance -- the distance between the valves and the rocker arms that operate them -- after the initial 50 hours of use, then again every 500 hours. Accessing the valves is made simpler by the pivoting cargo bed, which can raised to provide complete access to the engine's cylinder heads and valves.

Park the Mule on a level work surface and set the parking brake. Let the engine cool for a minimum of two hours; the engine must be completely cold to accurately measure and adjust the valve clearance.

Unlock the rear cargo bed, using the release lever, and lift the bed into its fully raised position. Remove the alternator cover and gasket from the right side of the engine, located just in front of the right rear wheel, using a socket and a ratchet.

Grasp the front cylinder spark plug boot, located just below the rocker cover marked with "OHV". Twist the boot a half-turn to release it from the spark plug, then pull the boot off of the end of the spark plug. Remove the spark plug using a ratchet and a spark plug socket. Remove the rear cylinder spark plug using the same method.

Remove the rocker covers and gaskets from both cylinder heads using a ratchet.

Place a socket and a breaker bar over the nut at the center of the alternator flywheel. Turn the flywheel clockwise until the front cylinder timing mark -- indicated by the number "1" -- is aligned with the mark imprinted into the crankcase breather cover directly above the flywheel. Wiggle the front cylinder rocker arms by hand, which should move slightly. If the rocker arms are stiff, rotate the flywheel clockwise a full turn.

Slide a blade-type thickness gauge between the front cylinder rocker arms and the valve tappets in the cylinder head. There should be a 0.010-inch air gap between the rocker arms and the tappets. With a 0.010-inch gap, the thickness gauge will slide through the gap with a slight resistance.

Hold the adjuster screw lock nut, located on top of the rocker arm, with a box-end wrench. Loosen the adjuster screw with a flat-head screwdriver. Turn the adjuster clockwise to decrease the air gap, or counterclockwise to increase the air gap. Recheck the clearance between the valve tappet and the rocker arm. Hold the screw in place and tighten the lock nut, once the valve clearance has been set to 0.010-inch. Repeat on the remaining valve, if needed. Skip this step if both front cylinder valves are within specification.

Turn the alternator flywheel clockwise one full turn until the rear cylinder timing mark, indicated by the number "2," is aligned with the mark on the crankcase breather cover. Wiggle the rocker arms to check for free play. Turn the flywheel a complete turn if the rocker arms are tight.

Check and adjust the rear cylinder valve clearances as described in steps 6 and 7.

Reinstall the rocker covers and gaskets onto the engine cylinder heads. Tighten the cover bolts to 16 foot-pounds using a torque wrench. Screw the spark plugs into both cylinder heads by hand. Tighten the spark plugs to 12 foot-pounds. Push the spark plug cable boots over the spark plugs until they snap into place.

Reinstall the alternator cover and gasket onto the engine. Screw the cover bolts into place until they are hand-tight. Tighten the cover bolts to between 35 and 43 inch-pounds, alternating between bolts in a crisscross pattern.

Lower the cargo bed until the release lever latches into a locked position.