Radne Motor Raket 95, Руководство пользователя

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Raket 95 Manual - English Raket 95 Manual - English
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9. Service tips
Experiences from the previous engine
model, Raket 85, have taught us that a
Raket engine should normally not require
any comprehensive levels of service
during a racing season, since we believe
that a Raket 95 engine will be used no
more than 50 times per season. We do
not believe that it should be necessary to
change bearings, sealing rings and piston
rings several times during a season, such
as is required with more extreme kart
engines. It is of course up to every driver
and mechanic to make their own deci-
sions about what they think is necessary
or best.
The following simple service routines can
however be said to fall into the category
of normal maintenance work:
1. Lubricating the clutch parts.
We recommend that you lubricate the
bearing of the clutch drum. The clutch it
self shall be clean and not lubricated.
2. Silencer
As we mentioned previously, it is possible
to drill out the rivets at the back edge of
the silencer.
When you have done this you can remove
the end of the barrel and thus even the
damping material that is lying wrapped
around the barrel. Assuming that the
carburettor is setup normally and correctly
it should not be necessary to change the
damping material during a season. How-
ever we would recommend a change prior
to the start of each new season.
3. Servicing the carburettor
The only aspect of your Raket 95 engine
that requires regular service is the
carburettor. A diaphragm carburettor is a
quite amazing component that is capable
of operating in chainsaws, cutters and
other testing applications whilst working
problem-free for several years at a time.
As long as you are careful to only refuel
using well-filtered fuel, and always drive
with the inlet silencer attached, then you
should also be able to get through a sea-
son without needing to disassemble the
carburettor for cleaning and control. On
the other hand you must possess the abil-
ity to clean and setup your carburettor. To
that end there now follows a short tutorial
in carburettor service.
The carburettor is a Tillotson 319 A. If we
follow the passage of the petrol through
the carburettor we will be able to quickly
describe the carburettor’s function.
The carburettor has two caps, one made
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,