Carburetion System; Idle Speed And Mixture Adjustment; Primer Nozzle Cleaning - Superior Vantage Engine O-360 SERIES Maintenance Manual

Idle Speed and Mixture Adjustment

Perform idle speed and mixture adjustments for
carbureted engines as follows:
•
Start the engine and warm up until oil and
cylinder head reach normal temperatures.
•
Check the magnetos.
(drop in RPM) is normal, proceed with the
idle adjustment, otherwise refer to the
Testing and Fault Isolation section of this
manual to determine cause and correct the
problem.
•
Set throttle stop screw so the engine idles at
the airframe manufacturer's recommended
RPM. If the RPM changes substantially
after making the following idle adjustment,
readjust the idle speed to the correct RPM.
•
Once the idling speed has been stabilized,
move the cockpit mixture control lever with a
smooth pull toward
position. Observe the tachometer for any
change during the "leaning out" process. Be
sure to return the mixture control to the "Full
Rich" position before the RPM drops to
where the engine stops.
engine speed of more than 50 RPM during
the leaning process indicates an excessively
rich idle mixture.
RPM (not preceded by a brief increase in
RPM) indicates that the idle is too lean.
•
If the above procedure indicates that the idle
adjustment is either too rich or too lean, turn
the mixture adjustment in the appropriate
direction and check this setting by repeating
the above steps.
setting that will obtain maximum RPM with
minimum manifold pressure. Make added
adjustments until the above check results in
a momentary increase of about 50 RPM.
Every time the idle is adjusted, the engine
should be run up to 2000 RPM to clear the
engine before proceeding with the RPM
check.
© March 2006 Superior Air Parts Inc.
Maintenance Manual
O-360 and IO-360 Series Engines

CARBURETION SYSTEM

If the "mag drop"
the "Idle-Cut-Off"
An increase in
An instant decrease in
The goal is to find a
•
Make the final tuning of the idle speed
adjustment with a closed throttle.
setting does not remain stable, check the
linkage. Loose linkage can cause erratic
idling. Consideration for the effect of
weather conditions and altitude on idling
adjustments must be made.

Primer Nozzle Cleaning

Remove the nozzle from the end of the fuel line
and cylinder. Submerge in a cleaning solvent
such as Stoddard solvent, MEK or equivalent
and allow to soak for a minimum of 10 minutes.
Remove from
compressed air and reassemble.
CAUTION: DO NOT USE A SHARP TOOL TO
CLEAN OR DISASSEMBLE FUEL NOZZLES.
NOTE: Under normal conditions, the shield
and screen are NOT removed from the
nozzle assembly.
necessary, both must be thoroughly
cleaned prior to reassembly.
shield must have a tight fit on the
body.
1
solvent, dry with
If removal is
73-20-00
Carburetion System
If the
clean
The