46
4WD MonsterTruck Destroyer XXL 1:8 No. 3 58 10
g) Check carburettor basic settings
Fine tuning of idle speed and full throttle can only be carried out with a well run in engine
The carburettor of Monster Truck “Destroyer XXL” is characterized by a material
combination of a new type made of plastic and metal.
The low thermal absorption of the synthetic material, compared to a carburettor made of
metal only, reduces the evaporation of the fuel mixture already in the carburettor.
Thus, the fuel supply can be more precise, even with a hot engine and can be regulated
in a simpler way.
Throttle stop screw (idle speed-adjusting screw)
The throttle stop screw is the small screw next to the idle speed-mix adjusting screw. It is
already pre-adjusted;
a readjustment should not be necessary. The idle speed adjusting screw regulates the
position of the slide carburettor (the choke limit stop) and therewith the carburettor outlet
in idle speed.
We recommend a carburettor outlet of approximately 1 mm.
Turning the adjusting screw clockwise widens the outlet, turning it anticlockwise causes the
slide to retract further, which reduces the opening.
Main nozzle needle (mix adjusting screw)
The main nozzle needle is located above the fuel supply to the carburettor. It is adjusted for the first start of the engine
and should not be modified yet.
The main nozzle needle regulates the air / fuel mix by full throttle. Turn the screw clockwise in order to make the mix “leaner” (to reduce the proportion of
fuel) and turn it anticlockwise in order to make the mix “richer”.
In the basic setting for the first start, the main nozzle needle must be completely screwed in then unscrewed by two to three rotations.
Idle speed- mix adjusting screw
The idle speed mix adjusting screw is the little screw on the side of carburettor linkage.
It is adjusted for the first start and should not be modified yet.
The idle speed mix adjusting screw regulates the air /fuel mix in idle speed and in the transition interval to full throttle.
Turn the screw clockwise in order to make the mix “leaner” (to reduce the proportion of fuel) and anticlockwise, if the mix should be “richer”.
Depending on fuel, glow plug used and environmental conditions, small modifications in the settings might be necessary at a later time.
In order to reset the factory setting proceed as follows:
Open the slide carburettor completely
Keep the slide open and turn the idle speed mix adjusting screw clockwise as far as it will go.
Now unscrew it turning it by 7.5 rotations anticlockwise.
h) Starting the engine
Combustion engine
The engine of Monster Truck Destroyer XXL is equipped with an
ABC assembly
.
ABC
means “
A
luminum”, “
B
rass” and “
C
hrome”.
Aluminum with its relatively small thermal expansion and small weight serves as material for the
piston. The light piston allows high revolutions and quick load-cycle changes through the small mass
inertia. The cylinder is made of brass with chrome-plated contact surface and has a slightly conical
shape which narrows upwards (in the range from 1 – micrometer). During operation, the upper part
of the cylinder heats via the glow plug and the combustion procedures; it expands, thus giving the
cylinder sleeve its exact cylindrical shape for the optimal tuning of the piston. In this way, piston rings
are preserved, which reduces frictional loss to a minimum and excludes leakages. These engines
are manufactured according to high technical outlays with precision machining. However, small
manufacturing tolerances cannot be avoided, just as little as slight unevenness and roughness of the
material.
In addition, there are deformations due to thermal and mechanical stress.
Thus, when driving the new engine, a certain break-in time must be observed.
During the break-in time, engine parts tune to one another, whereby maximal capacity is reached and
premature wear is avoided.
•
•
•
•
Throttle stop screw
Idle speed mix- adjus-
ting screw
Main nozzle
needle
Air suction opening
Summary of Contents for 23 58 10
Page 122: ...121 REELY 12 08 121 121 ...
Page 123: ...122 4WD MonsterTruck Destroyer XXL 1 8 No 23 58 10 ...
Page 124: ...123 REELY 12 08 123 123 ...