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12
CARE OF FUEL PUMP
NEVER disassemble the fuel pump or pressure
regulator. Their original performance may not be
restored after reassembly.
NEVER insert anything into the inlet or outlet
nipples in an attempt to clear a suspected
obstruction.
ALWAYS use fuel filters. Keep the fuel tank
scrupulously clean and filter all fuel as it enters the
tank
(e.g.via
an
O.S.'Super-Filter'
Code
No.72403050) and use a good quality in-line filter
between the tank and pump. Remember to inspect
filter screens at regular intervals and rinse clean as
necessary.
Do not clean the pump with organic solvent such
as kerosene, light machine oil, gasoline, thinner or
crc or the silicone rubbur parts inside is
detoriorated. Be sure to use methanol or fuel.
Do not more the pump adjusting screw at the
center a the adjustment gets out of order and the
parts inside is damaged.
Do not remain fuel in the pump. After finishing the
day's flight session, be sure to use out the fuel in
the pump. Stop the fuel flow to the pump with the
stopper and run the engine at idling to use out the
fuel in the pump. After stopping the engine, rotate
the engine by electric starter to eject fuel inside the
engine.
Pressure adjusting screw
13
IN
OUT
FUEL TANK AND PIPING
Install the engine and a muffler according to the
instructions supplied with the model. Then, connect
piping between tha muffler and fuel tank for muffler
pressurized fuel feed. Then, cut the silicone tube
supplied to 96mm and connect the pump and
carburetor with it.
Pump has fuel flow direction as shown in the sketch.
Be sure to connect between out nipple and carburetor
inlet nipple.
Next, connect piping from one-way valve for fuel
retur. There are two ways.
To return the fuel to the tank.
1.
Connect between one-way valve and fuel tank. Fit a
nipple on the tank. This system ensures stable fuel
supply even with the 3D flight which requires
successire big throttle works.
Clear the burr, if any, off the hole to fit the nipple
with a cutter knife. Also clean the tank with
methanol to remove the dust or tank cut-off
particle.
Fuel tank
Commercialy
available nipple
Nut
Washer
Summary of Contents for MAX-91SX-HRING C Spec PS VIPER
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