EN
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6.5.4. Proper timing/adjusting the valves
Improper valve clearance is noticeable by restless engine run, back-
fire or low performance.
In order to set up the valves follow these instructions:
• Remove the valve bonnet by unscrewing 2 screws (N1).
• Press the Outtake-valve (N4) and turn the shaft manually by hand
(pull the recoil starter) until both valves are closed (valves are
completely closed - push rods N3 on lowest position).
• The push-rods (N3) should be easily to move. Check the valve
clearance with a feeler gauge. The valve clearance should be ap-
prox. 0,15mm for both valves (N2) and (N4).
Should there be no feeler gauge available, normal typewriter paper is
fine (meaning two layers of paper is approx. 0,15mm also).
• Unscrew the check nut (N5) in order to set up the valves. Set up
the valves with the screw (N6) so that if the feeler gauge is moved
through the gap, there is a noticeable resistance. Then hold the
screw until the check nut is refastened.
• Check the valve clearance again and repeat the process if neces-
sary. Set up both the intake valve (N4) and the outtake valve (N2).
It has to be easy to move or turn the push rods. The valve springs must
not be broken and the push rod guides must not be worn. The position
(how deep is the nut) of the check nuts should be nearly the same.
Significant differences of nut deeps are a sign of incorrect assembly
or a damaged rocker arm, push rod or valve. In that case remove the
rocker arm entirely and pull out the push rod. Always replace damaged
or deformed parts..
When reassembling the push rods they have to lay on the appropriate
tapers of the camshaft (in the engine). Check whether the valves are
working properly by turning the camshaft.
The timing of this device is fixed and cannot be changed..
• After setting up the valves, reassemble the bonnet assembly.
Check whether the bonnet gasket is properly mounted.
6.5.5. Governing behaviour
The mechanical governer can be influenced in its regulation in diffe-
rent ways. The governing (how much the actual speed deviates from
the ideal speed) and the oscillating (engine speed oscillates arround
ideal speed) are important. These two characteristics disagree with
each other. Optimal balance is reached when the speed changing
causes a 1-time low oscillation.
This means: set up the speed without load. Then burden the motor
up with maximum load. Now the speed must first sink, then become
higher than the rated speed and then final go back to rated speed.
Engine speed should not oscillate around the rated speed.
To improve the governing, the regulating spring can be hung closer to
the middle of the regulation-arm. To decrease the oscillation the regu-
lating spring can be hung closer to the outside of the regulation-arm.
Normally a allready marked rated speed has to be reset after changing
the spring position – see the diagrams of the governor in 4.8.
Normally it is not necessary to change the speed or the behaviour. At
too low engine speed first check for any other causes of error (air filter,
diesel, valves, etc.)!
6.5.6. Muffler and colours of exhaust fumes
Backfire can be a result of loose screws on the outtake-manifold or
the muffler. In that case the fit of the screws as well as the state of
the gaskets should be checked. The exhaust pipe should be leak
and damage free
Residue must be removed from the exhaust pipe and the muffler. How-
ever, such residue indicates that either the wrong fuel is being used or
that oil is being burnt.
Too much exhaust back pressure can overheat the engine.
The colour of the exhaust gas can be an indication of the current
operation state of the motor:
motor is smoking
white or grey
water in the
fuel
drain the fuel tank
motor is smoking blue
motor oil is
being burned
check the oil level, valve guides
and compression
motor is smoking
black
too heavy load
check the air filter as well as the
injection nozzle. Maybe reduce
the load
6.5.7. Other
Unusual noises might be caused by worn piston, piston-rings, cylin-
der, piston bolt, bearings, etc..
Too little compression might be caused by worn piston, broken cy-
linder, incorrect set up or leaking valves.
If the motor gets too hot, the cause is either a too heavy load or a
clogged up ventilation system (air housing, ventilator).
If there is water in the fuel the engine does not start up, it smokes
white or it runs very restlessly. In this case drain the fuel.
Measure clearance
on this point
