Checking Basic Settings Of Carburettor - Reely MAMMOTH PRO RTR Bedienungsanleitung

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REPARATION
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HECK CARBURETTOR BASIC SETTINGS
The engine of Monster Truck chassis „MAMMOTH Pro" is equipped with an ABC
assembly.
ABC means "Aluminum", "Brass" and "Chrome".
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 – 2 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 aredeformations 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.
Thus, the break-in procedure must be carried out with the highest accuracy!
The following must be observed during initial break-in:
- Low engine speed
- Rich fuel- air mix
- Short runtimes with cooling down phases (each phase approx. 3 minutes)
- Runtimes (mere engine runtime) totaling approx. 45 minutes
Basic settings of the carburettor
The carburettor of Monster Truck "MAMMOTH Pro" 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 evaporati-
on 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 adjus-
ting 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.
44
Schiebevergaser (Abb. modellähnlich)
Main nozzle
needle
Throttle stop screw
Operating Instructions 4WD Monster Truck Chassis Item No. 23 32 35
Air suction opening
Idle speed mix-
adjusting screw