Subaru Robin EH90 - Manual (Page 13)

13
Figure 11
NOTE: The rocker arm jam nut must be held in place as
the pivot ball stud is turned.
When the valve clearance is correct, hold the
pivot ball stud in place with the Allen wrench and
tighten the rocker arm jam nut. Tighten the jam
nut to 168 in/lbs. (19 Nm) torque. After tightening
the jam nut, recheck valve clearance to make
sure it did not change.
• Install new valve cover gasket.
• Re-install the valve cover and torque to 60 in.lbs (6.8 Nm).
NOTE: Start all four screws before tightening, then torque
in a crisscross pattern. Make sure the valve cover
gasket is in place.
• Repeat the process for the other cylinder.
• Re-install spark plugs.
• Re-attach the spark plug wires to the spark plugs.
MAINTENANCE SCHEDULE
The owner/operator is responsible for making sure that all
periodic maintenance tasks are completed on a timely basis;
that all discrepancies are corrected; and that the equipment is
kept clean and properly stored. Never operate a damaged or
defective engine.
Disconnect the spark plug wires from the spark plugs,
and place the wires where they cannot come in contact
with the spark plugs before working on this engine.
• Operating the engine at high engine speeds is dangerous
and increases the risk of personal injury or damage to the
equipment.
• Operating the engine at low engine speeds with heavy
loads may shorten the engine’s life.
CARBURETOR ADJUSTMENTS
The carburetor of the engine is pre-set at the factory. The car-
buretor should not be tampered with because it would violate
EPA and CARB regulations and VOID THE EMISSION
CONTROL SYSTEM WARRANTY.
CHECKING AND ADJUSTING VALVE CLEARANCE
Check valve clearance and adjust (if necessary) after the fi rst
50 hours of operation and every 300 hours thereafter.
IMPORTANT: if not qualifi ed for doing this procedure or the
proper tools are not accessible, please take the engine/equip-
ment to the nearest Authorized Subaru Service Center to have
the valve clearance adjusted. This is a very important step to
insure a long life for the engine.
To adjust valve clearance:
• Make sure the engine is at room temperature
• Remove spark plugs and make sure that the spark plug
wires are out of the way.
• Remove the four screws attaching the valve cover with a
10 mm wrench or socket.
• Make sure the piston is at Top Dead Center (TDC) of its
compression stroke (both valves closed). To get the piston
at TDC, remove the intake screen at the front of the
engine to gain access to the fl ywheel nut. Use a ratchet
and a 36 mm socket to rotate the engine in a clockwise
direction. While watching the piston through the spark plug
hole, the piston should be observed moving up after the
intake valve closed. The piston is at TDC when it is at its
highest point of travel.
• Loosen the rocker jam nut (Figure 11). Use a 10 mm Allen
wrench to turn the pivot ball stud while checking clearance
between the rocker arm and the valve stem with a feeler
gauge. Correct clearance is 0.002-0.004 inch (0.50-0.1mm)
for both intake and exhaust valves.
0.076 mm
(0.003") GAUGE
JAM NUT
BALL STUD
CAUTION
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