Tennant 1550, Manual

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MAINTENANCE
1550 Gas/LPG/Diesel MM283 (8--02)
3--26
Injectors should be taken out only if engine is
malfunctioning as outlined below:
Misfiring
Knocking in one (or more) cylinders
Engine overheating
Loss of power
Smoky exhaust (black or white)
Increased fuel consumption
The faulty injector or injectors may be located by
loosening the line fitting nut on each, in turn, with
the engine running at a fast idle. This allows the
fuel to escape and not enter the cylinder. The
injector least affecting the engine performance
should be removed from the cylinder head and
reconditioned or replaced.
NOTE: No attempt should be made to adjust the
injection pressure without a proper testing pump
and pressure gauge. It is impossible to adjust the
setting of the injector with any degree of accuracy
without proper equipment.
PRIMING THE FUEL SYSTEM --
CONTINENTAL ENGINES (For machines serial
number 001000--001055)
Priming is necessary on initial installation of the
fuel injection system, after any subsequent
removal, or if the system was drained by running
out of fuel.
Before priming and venting, ensure that the
outside of the vent screws and surrounding area
is thoroughly clean to prevent dirt and foreign
matter entering the system.
NOTE: Electrical equipment such as starters
should be shielded during priming to prevent fuel
entry.
Carry out steps 1 and 2 while operating the fuel lift
pump priming lever.
1. Operate the fuel lift pump priming lever and
loosen the filter outlet connection until fuel
flows free of air.
2. Continue operating the fuel lift pump priming
lever while loosening the top vent valve and
the vent screw on the governor housing.
When fuel flows free of air, tighten the
connections. Stop operating the priming
lever and place it in the vertical position.
NOTE: Leaving the priming lever in the horizontal
position will lock the pump action stopping the fuel
supply.
3. Loosen any two injector high pressure pipe
nuts at the injector end. Set the accelerator
to the fully “open” position and ensure that
the stop control is in the “run” position.
Crank engine until fuel is free of air bubbles.
Tighten nuts.
NOTE: The bleeding operation may take a
considerable amount of cranking with the starter
to purge all air. It is important that the battery be
in good operating condition when bleeding.
If the engine will not start after bleeding, or any
other time, it may be an indication of a low battery
charge. If the voltage to the fuel shutoff solenoid
falls below 8 volts, the valve will shut off fuel to
the engine. This may happen during cranking if
the battery charge is low. The condition may not
be readily apparent since cranking speed might
still be good.
4. Start the engine.
A
B
C
D
01475
INJECTION PUMP VENTS
A. Top Vent Valve
B. Governor Housing Vent Valve
C. Injection Pump
D. Fuel Pump Inlet Connection