C A R B U R E T O R C O N T R O L S; Care And Maintenance - Protek Samurai 321B Instruction Manual

C A R B U R E T O R C O N T R O L S

The following procedure is recommended for this engine when the ProTek R/C P3,
PTK-2060 or PTK-2090 tuned pipe and fuel containing up to 30% nitromethane are used.
H I G H S P E E D N E E D L E ( N E E D L E VA LV E )
Use to adjust the fuel mixture when the throttle is fully open. (*3½ Turns from fully closed)
M I D N E E D L E ( M I X T U R E C O N T R O L VA LV E )
For changing the fuel mixture at mid speed and acceleration. DO NOT rotate the screw more
than one turn. (*2¾ turns from fully closed)
L O W S P E E D N E E D L E ( M E T E R I N G N E E D L E )
For adjusting the fuel mixture at partial throttle and idle speed to obtain steady idling and
smooth acceleration to mid speed. (*5½ turns from fully closed)
I D L E S C R E W ( T H R O T T L E S T O P S C R E W )
For setting the minimum idle speed. This is adjusted at the factory.
Carburetor Restrictor (Venturi)
High Speed
Needle
(Needle Valve)
Mid Needle
(Mixture Control Valve)
Ball Link
Thermo Insulator
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NOTE: We recommend
you double check
the needle settings
prior to beginning the
break in process. The
settings are set at
the factory, but slight
Slide Boot
readjustment may be
necessary to allow
Idle Screw
for changes in fuel
formula, gear ratio or
(Throttle Stop Screw)
clutch engagement
point.
*Factory default settings.
When screwing the needles all
the way in, the slide must be in
the fully open position.
Low Speed Needle
(Metering Needle)
C A R E & M A I N T E N A N C E
1 The small particles of foreign matter that may be present in any fuel may obstruct fuel
flow, causing erratic engine performance, unreliable operation or permanent damage to
the engine. It is recommended that a high quality in-line fuel filter be installed between the
fuel tank and carburetor.
2 Do not forget to clean or replace filters regularly to remove the dirt and other material that
can accumulate. Additionally, the carburetor may require occasional maintenance.
3 At the end of each operating session, drain out any remaining fuel from the fuel tank.
Then restart the engine to burn off any fuel that may remain inside the engine. Repeat
this procedure until the engine fails to start. This should be performed while the engine
is still warm.
4 Remove the glow plug and inject a small amount of after-run oil into the engine from the
glow plug hole in the combustion chamber. Then turn over the engine with the starter box
for 4 to 5 seconds to distribute the oil to the working parts inside the engine.
NOTE: Do not inject after run oil in through the carburetor, as this may cause the
carburetor o-rings to deteriorate. These procedures will reduce the risk of starting
difficulties or corrosion after a period of storage.
5 Finally, when cleaning the exterior of the engine, use an approved nitro cleaner. Do not use
gasoline, kerosene, or any petroleum based chemical as this could damage engine seals
and other components.
NOTE: This engine uses a silicone ramped crankshaft. DO NOT use light oil, water-
displacing oil, kerosene, or other petroleum based oils as an after run oil or to clean the
crank, as this will permanently damage the silicone. Use alcohol or nitro fuel to clean
the crank.
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