Valves/Valve Springs - Stihl 4180 Series Manual

7.9

Valves/Valve Springs

: Valves are distinguished by the
mark (1) on the valve head and
the head diameter "d"
Valves marked "A" and "B" or "
may be used for the inlet side only.
If used valves are reinstalled,
take care not to mix up the inlet
and exhaust valves.
Only valves marked "E" or "I" are
available as replacements. These
valves may be installed at either the
inlet or exhaust side – also in older
engines.
Assignment of valves to machines,
b 3.1
Remove the valves as follows:
– Remove rocker arms/pushrods,
b 7.3
– Remove the crankshaft, b 7.8.3
48
1
2
1
: Press valve spring retainer (1)
down and move it sideways so
that the valve stem is in the large
hole.
:
"
: Remove the retainer (1) with
valve spring (2).
– Take the valves out of the
cylinder.
1
: Inspect seats (1 and 2) on valves
and replace valves if necessary.
– Inspect valve seats in cylinder
head and valve heads for any
damage. Replace if necessary.
Valve spring retainer must engage
properly in groove of valve stem.
Reassemble in the reverse
sequence.
– When installing, check the valves
again, b 3.1
2
Series 4180 Powerhead