Rotek EG4-0210-5 Скачать руководство пользователя

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6.5.3.1. Cleaning the carburetor

Close the fuel cock and drain the gasoline using the drain-screw of
the carburator or by unsrewing the float chamber of the carburator.
Drain the gasoline into a glass container and check the drained ga-
soline for pollutants as well as water.
To clean the carburettor the air filter assembly must be removed.
Now unscrew the float chamber. Check and clean the float cham-
ber. The float must easily move up and down. The float is hollow and
must not be filled with gasoline. In that case the float is leaky - close
the hole with gasoline proof glue after removing any gasoline residue
or change the carburator.
The float triggers a needle valve. When you push the float upwards
and open the fuel cock - the gasoline may not flow on. If the float
pushed downwards the needle valve opens up and gasoline flows
into the float chamber. When the needle valve does not work pro-
perly the axis of the float can be removed and both the valve seat
and the needle should be cleaned accordingly. If the needle valve
is broken or the float has a hole, too much gasoline is released into
the float chamber.
Generally the carburetor can only be set up in very narrow borders.
The default is set by the used factory-needle. If necessary for special
usage (for example for usage at high sea level) the main nozzle must
be changed for one with a different diameter.
The adjusting screw for idle speed is responsible for mixing the alloy
during idle. The standard set-up is 2,5 turns open.
The carburetor is fixed to the device with two long screws below
the air filter case. Check that the nuts are all well-fastened in order
to avoid additional air getting into the device through the seals bet-
ween intake pipe and carburettor. If necessary, open the screws and
the seals between carburettor and intake pipe.

6.5.4. Cleaning and exchanging the air filter

If the air filter is loose or dirty the engine performance will be low (ex.
motor produces black gas under load). Therefor you must always
change the filter according to the maintenance intervals.
Open the nut on the top of the air filter box and take off the cover.
Also remove the nut from the air filter. The filter can now be taken
out of its base.
The filter element can be washed out in gasoline. Let the filter dry
completely after washing it. Check for any tears or other damage.
If the filter is damaged it must be replaced. Additionally clean the
inside of the air filter case with a dust cloth. Then place the filter
element on the base fix it with the screw and close the air filter case.

Sometimes tiny dirt particles are not visible with the naked eye. Indi-

cators for pollution are when the motor is producing black smoke (not

enough air). In that case exchange the air filter. Never put the motor

into operation without an air filter - this could damage your device.

6.5.5. Proper timing/adjusting the valves

Improper valve clearance is noticeable by restless engine run, back
fire or low performance.
To set up the valves follow these instructions:

• Remove the valve bonnet.
• Press the outtake-valve and turn the shaft manually using the

hand start until both valves are closed (valves completely out/
push rods at their lowest point).

• The push-rods should be easy to move. Check the valve clea-

rance with a feeler gauge. The valve clearance should be 0,10-
0,15 mm when the engine is cold for both valves.

Should there be no feeling gauge available normal typewriter paper is

fine (meaning two layers of paper).

• Unscrew the check nut in order to set up the valves. Set up the

valves with the adjusting-screw so that if the feeler gauge is
moved through the gap there is a noticeable resistance. Then
hold the screw until the check nut is refastened.

• Check the valve clearance again and repeat the process if ne-

cessary - check allways both valve clearance values.

When reassembling the push-rods they have to lay on appropriate ta-

pers of the camshaft (in the engine). Check whether the valves are

working properly by turning the camshaft.

The timing of this device is fixed and cannot be changed.

It has to be easy to move or turn the push rods. The valve springs must

not be broken and the push rod guides must not be worn. The position

(how deep the nut is) of the check nuts should be nearly the same.

Significant differences of nut depths are a sign of incorrect assembly

or a damaged rocker arm, push-rod or valve. In that case remove the

rocker arm entirely and pull out the pushrod. Always replace damaged