Valve seat width check
• Check that valve seat contact surface is neither damaged nor worn.
Check
• Measure valve seat width (A) (contact surface without soot deposits).
Technical specications
Intake valve seat width New 1.3 mm
Wear limit Max. 1.95 mm
New 1.6 mm
Wear limit Max. 2.4 mm
Result: Valve seat outside tolerance values.
Action:
• Grind or replace valve seat.
Valve guide clearance check
Check
• Apply a dial gauge at right angles with valve stem, preferably close to cylinder
head bearing point.
• Measure valve clearance by moving it. Repeat this procedure by moving dial
gauge by 90° (A, B).
Technical specications
Intake valve clearance
inside corresponding
guide
New, with 15 mm
valve lift
0.01 mm
Wear limit, with 15
mm valve lift
Max. 0.25 mm
Exhaust valve
clearance inside
corresponding guide
New, with 15 mm
valve
lift
0.02 mm
Wear limit, with 15
mm valve lift
Max. 0.25 mm
Result: Stem clearance outside tolerance values, even with new valve.
Action:
• Replace valve guide
Check
• Check valve spring for damages and wear
Result: Worn or damaged springs
Action:
• Valve spring replacement