Raket 95 Owner's Manual - page 21
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Raket 95 Manual - English
21
of metal while the other is mould cast.
Under the moulded cap lie a rubber
diaphragm and a gasket. There is a small
chamber on each side.
One of these chambers is connected to
the engine’s crankcase via a channel.
When the pressure in the crankcase
changes the pump diaphragm in the
carburettor will begin to move. On the
other side of the diaphragm there is fuel in
the other chamber. When the diaphragm
moves the fuel is pumped in and out of
the chamber. Two small lip valves that are
cut-out in the same piece of rubber en-
sure that suction from the tank occurs and
that the fuel is pumped further towards
the carburettor’s inlet valve. The pump
should sustain a pressure of approx.0.5
kp/cm2.
It is quite simple to check if the pump is
working correctly. Take off the spark plug
so that it will be easier to move around
the engine. Ensure that the fuel line is
correctly attached and that the carburet-
tor is sitting correctly on the engine. All
gaskets should be OK. Ensure that the
hose running from the crankcase to the
carburettor is in place. Press carefully (we
emphasise – CAREFULLY) down on the
master diaphragm which you can reach
through the small hole on the die-cut
cover of the carburettor. When you press
down on the diaphragm the inlet valve
opens. Turn the engine around and check
to see if there is any fuel coming from the
tank.
If no fuel is coming then you should firstly
loosen the fuel line from the tank and
blow into the hose. You should still be
pressing down on the carburettor dia-
phragm. You should feel that it is possible
to blow air through the carburettor. If
you are not able to blow air through the
carburettor then you should take off the
moulded cap, because there is obviously
something wrong. Firstly check the small
fuel strainer (this has article number 3043
in the spare parts list). It may be clogged.
After that it is time to focus on the pump
diaphragm itself. It could be worn out, but
that is actually difficult to determine with
the naked eye; however if it has been
used for a while then you should change
it! Remember that one should always
change the gasket when one changes the
diaphragm.
The rule is: The diaphragm should be fac-
ing the carburettor casing – otherwise the
lip valves will not seal!
Now the pump should be working OK,