MAINTENANCE
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W-GV4 Scalino outdoor — April 2017 — EN
5.4.4
Cleaning the external coolant radiator
Check the external radiator for leakage and air restriction. Make
sure the 12VDC fan is not blocked.
5.4.5
Replacing the fuel filter
Filter change is needed when the fuel is contaminated and as
part of preventive maintenance at least every 400 running
hours. Before changing the filter, clamp off the supply line.
Remove the hoses from filter and attach them on the new filter
again. The arrow on the filter housing indicates the direction of
the flow. A clogged filter results in a lack of output of the
engine and irregular running.
5.4.6
Air filter element
The W-GV4 Scalino is standard supplied with an air inlet filter
element. Filter change depends on environmental
contamination. Replace the air filter at least every 400 running
hours. The foam around the filter element can be cleaned by
compressed air. Do not use solvents to clean the foam. The
filter cannot be cleaned and must be replaced. Access to the
filter can be obtained by unscrewing the wing nut and pulling
the engine towards the service side. The filter can now be
replaced.
5.4.7
Checking hoses and electrical connections
Visually check cooling hoses, fuel hoses and electrical wiring,
paying particular attention to abrasion, wear and corrosion.
Have items replaced when necessary.
5.4.8
Retightening cylinder head bolts and adjusting valve
clearance
Both procedures have to be carried out with a cold engine. Be
sure to retighten the cylinder head bolts before adjusting the
valve clearance. First remove the valve cover.
Loosen the bolts slightly, remove the rocker assembly (the
rocker arms, shaft, and stays) and then retighten the bolts to
the specified torque in the numerical order illustrated
Figure 9: Cylinder head bolts
Tightening torques
Cylinder head screws M9x1,5: 47 to 51 Nm
Rocker arm bracket mounting: M6 x 1: 10 to 12 Nm
Standard torque chart
Size
M6x1.0
M8x1.25
M10x1.5
Nm
10.8+1.0
25.5+2.9
49.0+4.9
Apply 80% torque when tightening bolts to
aluminium alloy.
Valve clearance
When the engine is in cold condition both valves should have a
clearance of 0.15 ± 0.03mm. The adjustment has to be done at
top dead centre (TDC) of the compression stroke. There is a
marking on the flywheel, but this is invisible due to the PM
cover. One can find the TDC by rotating the flywheel and
watching each valve to open and close, though.
Rotating the flywheel can be realized by means of the flywheel
turning tool (article number 98002002; also refer to Figure 10).
Figure 10: Turning tool to move to Top Dead Center position
To be able to access the turning tool insertion point, first
disassemble the water pump. Rotate the flywheel clockwise,
allowing the exhaust valve to open and close and the intake
valve to open and close. After the intake valve has closed,
rotate the flywheel clockwise an additional ¼ turn. At this
position the piston will be on compression stroke and both
valves will be closed allowing valve clearance adjustment to be
completed.
Before closing the valve cover apply some oil to the contact
surface between the adjusting screw and push rod. Use a new
valve cover gasket.
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