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LOCATING AND RECTIFYING POSSIBLE TROUBLES.
TROUBLE.
Failure to Start.
Erratic Slow Running.
"Loss of Power.
Excessive Oil
Consumption.
Engine Runs Harshly.
Engine Cuts -Out at
Large Throttle
Openings.
POSSIBLE CAUSES.
Faulty plug. Faulty H.T. lead.
Contact breaker points dirty or out
. of adjustment.
Pick-up brush worn or broken. Slip
ring oily.
Failure of petrol to reach
mix
tug
chamber.
Broken throttle wire.
Pilot adjustment requires re-setting.
Worn inlet valve guide.
Faulty valve seats.
No tappet clearance.
Exhaust valve lifter holding valve off
Mat.
Front chain too tight.
Loose carbon wedged on valve seat.
Broken piston rings.
If accompanied by black smoke from
exhaust, broken piston rings, worn
rings or barrel.
Oil pump not returning.
If unaccompanied by exhaust smoke,
faulty oil pump timing cover
connection.
Mag. chain too tight.
Dirt in carburetter.
REMEDY.
Remove plug, place plug body in
contact with cylinder, revolve
engine. If blue spark of fair
intensity occurs, plug and ignition
O.K.
If no spark, change plug, and if still
no spark, remove plug from H.T.
lead, hold end of lead 1/8' from
cylinder and revolve engine. In the
event of there being still no spark,
examine contact breaker points and
check their gap. Examine pick-up
brush and clean slip ring.
Ensure that ‘ petrol is flowing down
feed
pipes. Clean carburetter.
Ensure that throttle slide rises as
twist grip is revolved.
With throttle about 1/-8' open and
air closed, adjust pilot screw until
good
idling is obtained.
Remove valve spring and test valve
for side play in guide.
Examine and re-grind as necessary.
Check and re-set as required.
Ensure that there is some movement
in cable before lever begins to lift
valve.
Adjust.
Can usually be removed by kicking
engine over a few times.
Examine and replace as required.
Examine and make necessary replace
ments.
With engine running an intermittent
stream of oil should be seen upon
opening oil tank filler cap.
Ensure that the necessary pressure is
generated between timing cover and
oil pnmp nipple fibre washers as
instructed in para. 26.
Adjust as in para. 32.
Clean Mid re adjust.