Special Procedures Engine; Setting The Rpm; Adjusting Valve Clearance And Retightening The Cylinder Head Bolts - Whisper Power W-SQ16 User Manual

TROUBLE SHOOTING
5.4

SPECIAL PROCEDURES ENGINE

5.4.1

Setting the RPM

RPM is set by the manufacturer and should not need
readjustment! However a very slight offset after running in
could occur. RPM can be measured by a frequency meter.
Before readjustment check any other explanation for the
wrong speed. Engine speed is set at the factory at nominal
1500 (50 Hz) RPM. A RPM drop of 5% at full load is
acceptable. Therefore a no load setting should be at ±
1575 RPM = 52.5 Hz. Under no circumstances should the
RPM be under full load below 1470 RPM = 49 Hz. When
no cause can be found for a wrong speed, the setting can
be adjusted:
Fig. 25 1 =Adjustment screw operational RPM
2 =Adjustment screw max. RPM
It is very important to identify the correct setting assembly
(refer to fig. 25). The screw is to be locked in position with
the lock-nut.
32
5.4.2 Adjusting valve clearance and
retightening the cylinder head bolts.
Both procedures have to be carried out with a cold engine.
When both procedures are carried out be sure to retighten
the cylinder head bolts before adjusting the valve
clearance. When retightening the cylinder head bolts,
drain the coolant by removing the drain plug (ref. to fig. 2).
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
(ref. to fig. 24).
Tightening torque cylinder head bolt:
Rocker stay tightening torque:
Long bolts
Short bolts
Fig. 24 Tighten sequence cylinderhead bolts
The clearance of both (intake and exhaust) valves should
be 0.25 mm in cold condition. Set the piston of the first
cylinder to be adjusted to top dead centre (T.D.C.) of
compression stroke.
January 2009 / W-SQ16 for mobile applications / EN
118 ± 5 Nm
15 ± 2 Nm
12 ± 1 Nm