MegaTech MTC 7805, Owner'S Manual

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Starting Engine
General – During break-in, it may be necessary to leave
the glow plug igniter attached to the engine to keep it run-
ning while the fuel-air mixture is adjusted “rich” for
break-in. This is normal.
The high speed needle valve adjusts the fuel-air mixture
only at higher throttle settings and will not affect low
speed. The low speed needle valve affects the fuel-air
mixture only from idle through mid-range. The idle speed
stop screw is a mechanical stop that determines only how
far the carburetor barrel will close, and has no effect on
fuel-air mixture. There must be approximately a 1mm
opening in the carburetor barrel when the carburetor is
closed (idle position). If this adjustment is not correct,
(and the engine idle speed is too slow) it will be nearly
impossible to set the low speed needle valve properly.
After priming the engine, and turning on the transmitter
and receiver, pull the engine starter handle two or three
times to circulate the fuel in the engine.
Important! Whenever you start the engine, always pull
the starter handle with short, quick pulls straight away
from the engine. Do NOT pull the handle all the way out,
or at any angle that allows the cord to contact any part of
the engine or truck. Always let the starter handle back in
slowly after each pull, do not let go and allow the handle
to snap back into the engine. Make sure the throttle trig-
ger is set at idle speed.
Break-In procedure
Attach a fully charged 1.5 volt glow plug igniter to the
engine, and wait three seconds to allow the glow plug to
heat up. Start the engine using short, quick pulls on the
starter handle. Once the engine is running, observe the idle
speed. If the speed is too high (above 3000 RPM), open
the low speed needle valve (counterclockwise) until the
engine speed slows to a safe idle. If the engine stops or
runs too “rich” (lots of smoke and liquid fuel droplets
coming from the exhaust), then close the low speed needle
valve (clockwise) until the engine reaches a reliable idle
speed. Adjust the low speed needle valve so that the en-
gine idles as “rich” as possible while still running. If the
engine will not keep running reliably at idle speed during
this time, turn the idle speed stop screw ½ turn clockwise
to increase the minimum speed.
As soon as you are able to keep the engine running (with
the glow igniter attached if necessary) at a reliable, ultra-
rich idle, run
two full tanks of fuel through the engine at
the rich idle setting.
If the cylinder head temperature reaches 230 degrees F,
shut down the engine, let it cool completely, and start it
again.
After idle break-in, the low speed needle valve can now be
adjusted for optimum low and mid-range running. With
Tempest Gladiator 8
Megatech’s MegaNiter rechargeable glow
plug igniter allows easy starting, and can be
left on to keep the engine running reliably
during the rich mixture break-in period.
Location of Low Speed Needle Valve
Starter Handle
Starter Handle