nifty 170SD series Operating/Safety Instructions Manual page 25

4.1.14
PETROL (GASOLINE) BOX:-Located adjacent to the petrol (gasoline)engine, the Petrol (gasoline)
Box combines all of the functions for dual power operation, as well as controlling the petrol engine
itself. The relays in this box control Starting, High Throttle, Pump Dump, Duty Selector and Engine
Stop. There is also an integral Thermal trip, which protects the Throttle solenoid and other
functions.
4.1.15
LPG OPERATION:-On machines equipped for LPG operation (propane) the Honda engine will also
have an LPG vaporiser, valve lock and micro-vac switch. The supply and regulation of the propane
is governed by the installed gas bottle and regulator. The vapour take-off system requires a
vaporiser to convert the liquid gas into an airborne mixture. This is then held by the micro-vac
switch and valve lock until the engine turns over, creating a vacuum on the inlet to the engine
carburettor. The micro-vac switch then tells the valve lock to open, admitting the gas to the engine.
If the engine is halted, the system returns to normal, holding the gas until a re-start is attempted.
When running on Petrol, the main tap to the gas bottle should be securely closed, to prevent the
engine from trying to run on a mixture of the two fuels. If starting to run on LPG, it should be
ensured that all petrol is discharged from the carburettor bowl before changing to LPG, since the
engine will not run satisfactorily if any petrol is in the carburettor bowl.
4.1.16
FUNCTION SELECTOR: Two Wheel Drive: Situated adjacent to the drive/outrigger controls is a
two position hydraulic hand valve which allows the machine's hydraulics to be directed to either the
outrigger/drive circuit (downwards) or the boom operation (upwards). The outrigger/drive circuit
requires the booms to be lowered in order to operate. The boom circuit needs all four outriggers to
be in contact with the ground before it will operate.
Four Wheel Drive: The hand operated duty selector is situated adjacent to the drive/steer joystick
and the electrical solenoid outrigger controls. Grasping the handle automatically routes the hydraulic
flow through to the outrigger and drive circuit and at the same time operates the micro switch to run
the appropriate power option chosen. This then permits the use of either jack deployment or
machine drive. Releasing the spring loaded handle returns it to the boom position. As soon as the
boom raises, the electric micro switch is disabled denying the use of the outrigger and drive
functions whilst elevated. As before, the boom circuit needs all four outriggers to be in contact with
the ground before it will operate.
4.1.17
SPEED CONTROL: A two position selector allows high throttle for the engine to be selected, or twin
power pack operation for fast speed duty. This will operate when the booms are lowered, to allow
fast set-up of the outriggers, and fast drive speed.
4.1.18
2WD: Machine is two wheel drive and front wheel steer. Braking is hydrostatic on the front wheels
and with mechanical parking brakes on the rear wheels. Speed control is fully proportional with hi/lo
throttle control and series/parallel switching of the drive motors. (Tortoise/hare).
4.1.19
4WD: This variation is four wheel drive and front wheel steer. Braking is hydrostatic on all wheels
and with fail-safe hydraulic parking brakes on the rear wheels. Speed control is fully proportional
with hi/lo throttle control and series/parallel or parallel/parallel switching of the drive motors
(Tortoise/Hare).
English/USA 09/03
Operating & Safety Instructions
SD Series
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