Technical data

F
lywheel / Stator / Reversing Gear / Starter / Cylinder head
Assemble Flywheel Cylinder head
Test Valve seat tightness, piston gap
22
- Fasten the stator in the crankcase and screw on
the attaching clamp
- Install the flywheel. Tightening torque of the
flywheel screws is 7.0 kpm
- Attach the reversing gear
- Attach the starter
- Adjust the gap with a corresponding cylinder
foot gasket
The gasket set contains gaskets of various
thicknesses.
NOTE
When installing the cylinder head pay close attention
to the following points. It is imperative that a new
cylinder head gasket be used and pay close
attention to valve sit back and tightness
Tightness is checked by filling fuel into the
intake or exhaust channel. If nothing leaks
through, the valve seat is tight.
CAUTION
Do not damage the rubber sealing rings for the
decompression lever, resp. decompression shaft
and stop pin
After replacing cylinder, piston, connecting rod,
crankshaft or crankcase, measure the gap
between cylinder and piston upper surface at
TDC (42).
Use the measuring bridge No 74 64 1 333 544
and clamping piece No 74 64 1 333 546 with
measuring gauge, for measuring the gap.
- Mount the completely assembled cylinder head
onto the cylinder
- Fasten the cylinder head with the aid of socket
wrench No 6425 evenly and crosswise with the
required tightening torque.
Tightening torque of the M8 hex nut on studs
(tension rod) for the fastening of cylinder and
cylinder head – 35 Nm (3.5 kpm)
NOTE
Oil threads lightly. However, do not use molykote.
Seal locking screws in the oil space of the cylinder
head with a permanently elastic sealing compound
(e.g. Atmosit or similar)
Repair Data
Cylinder Head Dimension D7 nominal
values
Piston gap (A)
Cylinder head (b)
gasket
Cylinder shim
mm
mm
mm
0.55 – 0.65
1.50
0.1/0.2
CAUTION
If the gap is too small piston, cylinder head and
valves may be damaged. If the gap is too large,
the engine loses performance.