CONTENTS
SOUNDS
UNDERHOOD
RHYTHMIC

MUFFLED, BELL-LIKE SOUND

CONDITION(S)

• MUFFLED, BELL-LIKE SOUND (PISTON KNOCK OR SLAP)
• NOISE IS LOUDER WHEN ENGINE IS COLD AND BECOMES QUIETER AS ENGINE WARMS UP
• NOISE INCREASES AS ENGINE IS PUT UNDER LOAD

POTENTIAL CAUSE(S)

CHECK THIS FIRST:

1. EXCESSIVE PISTON CLEARANCE
Have piston professionally serviced.

CHECK THIS NEXT:

2. COLLAPSED PISTON SKIRT
Have piston professionally replaced.

CHECK THIS LAST:

3. WORN CYLINDER
Have cylinder professionally serviced.

CONTENTS
ENGINE BACKFIRES
ENGINE KNOCKS OR PINGS