Because of the har1ened steel exhaust
valve seat Inserts In the exhaust valve posI-
tions, It Is recommendedthat the valves be
refaced on a nnchlne IIBdefor th 1s purpose
and the seats be reground wIth a hIgh speed
valve seat grInder
As a final operat ton, the valves and
seats maybe pol1shed by Iappfng theminwlth
a s:Jall amount of valve gr-tndtng compozid,In
thIs mannera perfect seat can be obt arned
which VillI gIve manyhours
0
f satisfactory
servIce.
:::ARBJRETOR ADJUSTI.:il~TS
The carburetor has two adjustment ~
dle valves for correcting changes in fuels ami
atmospheric condItions. These adjustments are
knownas the nIdl1ng Adjustment Needle" and
the "L a.inAdjustment Needle".
The idlIng adjustment needle, located
to the rear on outside of carburetor upper
body, controls the flow.af air for the idl1ng
mixture. Turning in this needle shuts off the
flO¥lof air and makesa richer fuel mixture.
Turntng out makesa leaner mixture. A good
place to start for adjustment
w
one and one-
half turns open. Donot expect a newmotor,
that is too "stiff" to rock freely ancomprea-
Sion, to idle smoothly.
To get the proper idl1ng speed, set
the stop screw on the throttle valve arm of
carburetor. Turn stop screw to right to in-
crease idle speed, to left to decrease idle
speed.
The main jet adjusting needle, located
on side toward engine block on the rear of
carburetor upper body, is for admitting more
fuel to the engine than is supplied by the
min jet, which maybenecessary due to the
variation of fuels andatmospheric comttaons,
Turning out admits more fuel andmakes a rich
mixture. DOnot force the needle downen its
seat as this w111cause damageto these parts.
JlAGNETO
The contact points must be kept clean
and properly spaced. If they are pyra.mided
or pitted, they should be madesmoothwith a
tongsten file or a stone, andadjusted to al-
Iowa gap of
.012"
to
.015"
when open on RV4
ma.~etos, and
.020
on FMmagnetos.
The spark plug points should lBvea
IJlP
of
.030
to
.035
Inch.
The magneto Is manufactured
tu'
a reU-
able co:n~ny and is serviced through tts many
authorized service statIons.
RAiJIATOR AND COOLING SYSTI::M
Only rain or soft water should beused
in the radiator if ava11able. Hard or alka-
line water will froma scale whIchwIll Impair
radiatIon if allowed to build up in the cool-
ing system. Tne use of washing soda
will
help
to loosen thIs scale; and where~'onlyhard or
alkal1ne water 15 available tie washing
SCXh
should be used at regurar intervals and be-
fore the accumulation of scale beconesmavf
enoughto scale off and stq>up tie radiator
passagea,
In cold 'weatheranantI-freeze solu-
tion can be used in the radiator.
1)0
not run engtne wlthout water or
somecooling solution in radiator.
Never pour cold water in a hot motor
whenthe water is low.
To drain coolIng system removepipe
plug from bottom of radIator on right hand
side.
CUJTCH
The clutch Is of the spr
t
ng loaded
sIngle plate dry dtsc type. The release
engagement;Is by movement,of the clutch sntr-
ter a nd the throwout bear-Ing contacting the
3 release levers.
Each release lever has an adjustIng
screw whIch Is for the p.lI1)OOeof regulating
the level' contact
wIth
the throwout bearing.
As the clutch racrngs wear, the release le-
vers movenearer to the throwout bearingam
the only clutch adjustment necessary Is to
prOVideclearance at thIs poInt.
To adjust: Turn adjustIng screws to
allow a clearance of 1/4" between the ends
of each of the three release levers andthe
throwout bearIng.
FAN BELTS
To adjust fan belts, loosen
tlE
four
capscrews holdIng the air cleaner bracket to
the front of the motor, andby using a smll
bar turn pumphouslni clock-wIse unt11 the
fan belts have
1-1/2
slack lII1d-waybetween
the pulleys. TIJhten the capscrews evenly
to prevent leakaee.
Donot tighten fan belts moreor of-
tener than necessary to prevent slippage.
FRONT WHEEL BEARING AUJUSTMalT
The front wheels are mounted<ntaper
roller bearings. At frequent intervals re-
movethe we1ght from the wheels am examIne
for stde PlaY. If si de play exrata it will
be necessary to adjust bearIngs.
To adjust beartngs , relnorethe hub
cali
and tap bolt and spIndle washer. Between
spindle washer and endof spIndle is a series
Of sntma, Removeenough sh1ms to take up
play but not enough to bind bear mga, Tap
bolt must be tightened securely to prevent
its backing out.
The insIde of the wheel hub is pro-
vIded with a felt washer 10protect
tm
bEar'-
tngs from dirt and to retaIn the grease In
the hub. ThIs washer should be replaced each
season when\vorkingunder average <Xnllti<l18.
6
