MAINTENANCE
235 MM166 (5--91)
3-18
The initial setting of the main fuel needle valve, if
it is present, is made by lightly turning it all the
way in, then turning it out two and three-quarter
turns. The fuel tank should be approximately
one-half full and with the engine running at
approximately 2200 RPM. Final adjustment is
made with the engine warm. Turn the main fuel
adjusting needle valve out until the engine begins
to lose speed (rich). Note the position of the
needle. Then turn the needle in. The engine
speed may increase, then it will decrease as the
needle is turned in (lean). Note the position of the
needle. Set the needle half way between the rich
and lean positions.
B
A
03496
CARBURETOR ADJUSTMENTS
A. Idle Needle Valve
B. Main Fuel Needle Valve
FUEL SYSTEM -- LPG
LPG FUEL SYSTEM
The LPG fuel system is made up of six
components which are: the LPG fuel tank,
pressure relief valve, fuel filter lock,
vaporizer-regulator, secondary regulator, and the
carburetor.
Liquid LPG fuel flows from the LPG tank, under its
own pressure, to the pressure relief valve. This
valve is normally closed, preventing LPG fuel from
escaping into the atmosphere. The valve opens to
relieve pressure if the fuel pressure exceeds
system limits. From the pressure relief valve, the
LPG fuel is piped to the fuel filter lock. The fuel
filter lock filters unwanted tank scale and deposits
out of the LPG fuel. The fuel filter lock also stops
the flow of LPG fuel when the engine is not
operating. The oil pressure switch controls the
fuel filter lock. When the engine oil pressure is 4
psi (30 kPa) or greater, the oil pressure switch
permits an electrical current to open the fuel filter
lock which allows LPG fuel to flow on to the
vaporizer, then the regulator. The oil pressure
switch is bypassed when the engine is being
started, allowing LPG fuel to flow.
The vaporizer converts the LPG fuel into a
gaseous LPG fuel. Within the vaporizer, the
gaseous LPG fuel is sent to the primary regulator.
The primary regulator section reduces the
pressure of the LPG fuel. From the primary
regulator section of the vaporizer, the LPG fuel is
sent to the secondary regulator. The secondary
regulator reduces the LPG fuel pressure to the
level required by the carburetor. Then the fuel is
sent to the carburetor where it is finally metered
into the air flow which is sent to the engine
combustion chamber.
A
B
C
D
E
F
G
H
04232
LPG FUEL SYSTEM
A. Carburetor
B. Secondary Regulator
C. Vaporizer-Regulator
D. Fuel Filter Lock
E. Pressure Relief Valve
F. Tank Service Valve
G. LPG Fuel Tank
H. Oil Pressure Switch
Summary of Contents for 235
Page 1: ...235 MM166 Operator Manual ...
Page 6: ...ABOUT THIS MANUAL 235 MM166 5 91 d ...
Page 14: ...SPECIFICATIONS 235 MM166 5 91 1 2 ...
Page 18: ...SPECIFICATIONS 235 MM166 5 91 1 6 ...
Page 20: ...OPERATION 235 MM166 5 91 2 2 ...
Page 36: ...OPERATION 235 MM166 5 91 2 18 ...
Page 49: ...MAINTENANCE 3 13 235 MM166 3 94 03460 HYDRAULIC SCHEMATIC ...
Page 61: ...MAINTENANCE 3 25 235 MM166 3 94 03489 ELECTRICAL SCHEMATIC ...
Page 62: ...MAINTENANCE 235 MM166 3 94 3 26 03489 ELECTRICAL SCHEMATIC AUXILIARY SIDE BRUSH ...
Page 78: ...MAINTENANCE 235 MM166 3 94 3 42 ...
Page 80: ...APPENDIX 235 MM166 5 91 4 2 ...