16 ENGINE 140
16.4.23 Checking the valves
305605-10
– Check the run-out at the valve plate.
Valve - run-out
On the valve plate ≤ 0.05 mm (≤ 0.002 in)
» If the measured value does not equal the specified value:
– Change the valve.
302809-10
–
Check sealing seat
on the valve.
Valve - sealing seat width
Intake 1.60 mm (0.063 in)
Valve - sealing seat width
Exhaust 2.00 mm (0.0787 in)
» If the sealing area is not in the center of the valve seat or deviates from the
specified value:
– Machine the valve seat.
16.4.24 Checking valve springs
305593-10
– Check the valve springs for fractures and wear (visual check).
» If the valve spring is fractured or worn:
– Change the valve spring.
– Measure the valve spring lengths.
Valve spring
Minimum length (without valve
spring cap)
42.3 mm (1.665 in)
» If the measured value does not equal the specified value:
– Change the valve spring.
16.4.25 Checking valve spring retainer
305594-10
– Check the valve spring retainer for fractures and wear (visual check).
» If the valve spring retainer is fractured or worn:
– Change the valve spring retainer.
– Measure the thickness of the valve spring retainer.
Valve spring cap - thickness 2.4… 2.5 mm (0.094… 0.098 in)
» If the measured value does not equal the specified value:
– Change the valve spring retainer.
16.4.26 Checking the cylinder head
305595-10
–
Check valve guides
with the special tool.
Limit plug gauge (59029026006) ( p. 230)
» If the special tool is easy to insert into the valve guide:
– Change the valve guide and valve.
– Check the sealing area of the spark plug thread and the valve seats for damage and
cracking.
» If there is damage or cracking:
– Change the cylinder head.