Speed/Governor Adjustment; Ignition Test; Oil Alert Test; Start Mechanism - DeWalt DW168F Manual

pRoBlEM CausE
Excessive vibration/ Loose/worn connecting rod
knocking
Carbon in combustion
chamber
Bent crankshaft
Engine mount damaged
Timing out
Perform Test Checks

spEED/GoVERnoR aDjusTMEnT

If speeds are out of adjustment use this procedure to reset to factory settings.
1. Back off both idle adjustment screws far enough so they are out of the way.
noTE: This is the black plastic screw (L3, Q2) at carburetor and the screw with the
black spring under the head on the solenoid L-shaped linkage (if equipped).
C5
L3, Q2
E5, Q5
2. Loosen the governor arm (E5, Q5) from the shaft (F2) coming out of the top of engine.
on 9 and 13 hp engines:
Rotate the shaft counterclockwise with the governor arm held to the right at wOT
(wide open throttle). Make sure governor arm remains straight and does not pivot at
the joint in the middle (if equipped). Retighten governor arm to shaft in this extreme
position.
on 6.5 hp engines:
Rotate the shaft clockwise with the governor arm held to the right at wOT (wide open
throttle). Retighten governor arm to shaft in this extreme position.
3. Governor spring (large silver) should be in the hole on the governor arm closest to the
shaft.
4. Back out high speed adjustment screw (N5, Z4) on top of the engine at the small silver
lever. A few complete turns will do.
5. Start the engine. If it hunts (speed varies up and down.), move the governor spring to
the outer hole, if power is too low move it back in toward the shaft. noTE: Hunting is
unpredictable and sometimes the opposite movement of the spring helps.
6. Engine will probably be running slow. Adjust high speed to 3600 rpm by turning high
speed screw (N5, Z4) on top, in to increase speed and out to slow down. If engine still
runs to fast, governor arm may still be out of adjustment on shaft or it has moved since
tightening. Or there could be an internal governor issue (this is rare).
noTE: If governor arm was over tightened to shaft and has no gap at the end of the
arm next to the shaft, over tightening of the governor arm will not result in sufficient
holding force to shaft. The governor arm must be replaced.
7. With engine off, ensure idle linkages on solenoid are not binding and are free to move
the full travel. Also make sure throttle linkage from carburetor to governor arm moves
back and forth freely.
soluTIon
Repair connecting rod
Clean carbon from chamber
Disassemble crankcase and
repair
Check engine mounting bolts
or replace rubber isolator
Check flywheel key
N5, Z4
f2
8. Ensure the idle screw (with black spring under the head on the L-shaped lever on the
solenoid) is backed out far enough to just clear touching the governor arm with idle
control turned off.
9. Start the engine. Turn idle control on after engine has warmed up some. Solenoid
should push governor arm and throttle to the left toward carburetor and the black plastic
throttle should stop up against black plastic screw (L3, Q2). Adjust the idle speed to
2700–2800 RPM by adjusting this screw in to increase idle speed, back it out to reduce.
If solenoid does not push lever over far enough to touch black plastic screw (the screw
with the black spring on the L-shaped solenoid lever) can be turned in to make this
happen. both of these screws can be adjusted in our out so one is not at the extreme
of it's adjustment length.
10. Cycle idle control switch on and off a few times and check both high speed and idle
speed to ensure they are still correct.

IGnITIon TEsT

ChECk FoR spaRk
waRnIng: Risk of explosion. Spilled gas o line and it's vapors can be come ignited from
sparks from smoking products, electrical arcing, exhaust, flame, gas es and hot engine com-
ponents such as the muffler. Make sure there are no sources of ignition, such as smoking
products near servicing location. Wipe any fuel spillage from engine.
waRnIng:
• Never hold the spark plug wire with wet hands while performing test.
• Wipe any fuel spillage from engine.
• Make sure the spark plug is not wet with fuel.
• Do not allow sparks near the plug hole.
1. Remove the spark plug from the cylinder head.
2. Ground spark plug against air shroud as shown.
3. Place the on/off switch in the "ON" position and
crank the engine.
4. Check to see if the spark bridges the electrode
gap. If you can see the spark (this may be difficult
in bright daylight) the problem is most likely not the ignition system. If spark plug fails
to spark, see Flywheel Ignition Inspection.

oIl alERT TEsT

perform this check if the engine will not start and other troubleshooting attempts
have failed. Ensure oil is a proper level, see oil under maintenance.
Engine will not start:
Disconnect the lead from the oil alert
sensor and directly connect the
leads from the ignition switch and
the ignition bypassing the low oil
sensor. If the engine starts replace
the sensor.
Engine will not stop:
with the engine running disconnect
the oil alert sensor lead and ground
it against the engine. If the engine does not stop replace the sensor.
21