Lycoming TIO-540-A1A, Руководство оператора

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LYCOMING OPERATOR’S MANUAL SECTION 5
TIO-540 SERIES – ANGLE VALVE CYLINDER HEADS MAINTENANCE PROCEDURES
If step (4) indicates that the idle adjustment is too rich or too lean, turn the idle mixture
adjustment in the direction required for correction, and check this new position by repeating the
procedure in step (4). Make additional adjustments as necessary until a check results in a
momentary pick-up of approximately 50 RPM. Each time the adjustment is changed, the engine
should be run up to 2000 RPM to clear the engine before proceeding with the RPM check. Make
final adjustment of the idle speed adjustment to obtain the desired idling RPM with closed throttle.
The above method aims at a setting that will obtain maximum RPM with minimum manifold
pressure. In case the setting does not remain stable, check the idle linkage; any looseness in this
linkage would cause erratic idling. In all cases, allowance should be made for the effect of weather
conditions and field altitude upon idling adjustment.
3. LUBRICATION SYSTEM.
a. Oil Grades and Limitations –
Service the engine in accordance with the recommendations shown in
Section 3.
b. Oil Suction and Oil Pressure Screens –
At each fifty hours inspection remove, inspect for metal
particles, clean and reinstall.
NOTE
On installations employing external oil filters, step 3, b is not practical at this time. But
should be observed at the 100-hour inspection
c. Oil Relief Valve (Non-Adjustable) –
The function of the oil pressure relief valve is to maintain engine
oil pressure within specified limits. The valve, although not adjustable, may be controlled by the
addition of a maximum of nine STD-425 washers under the cap to increase pressure or the use of a
spacer (Lycoming P/N 73629 or 73630) to decrease pressure. A modification on later models has
eliminated the need for the spacers. Particles of metal or other foreign matter lodged between the ball
and seat will result in faulty readings. It is advisable, therefore, to disassemble, inspect and clean the
valve if excessive pressure fluctuations are noted.
d. Oil Relief Valve (Adjustable) –
The adjustable oil relief valve enables the operator to maintain engine
oil pressure within the specified limits. If the pressure under normal operating conditions should
consistently exceed the maximum or minimum specified limits, adjust the valve as follows:
With the engine warmed up and running at approximately 2000 RPM, observe the reading on the oil
pressure gage. If the pressure is above maximum or below minimum specified limits, stop engine and
screw the adjusting screw out to decrease pressure and in to increase pressure. Depending on
installation, the adjusting screw may have only a screw driver slot and is turned with a screw driver;
or may have the screw driver slot plus a pinned .375-24 castellated nut and may be turned with either
a screw driver or a box wrench.
4. CYLINDERS.
It is recommended that as field operation, cylinder maintenance be confined to
replacement of the entire assembly. For valve replacement, consult the proper Overhaul Manual. This
should be undertaken only as an emergency measure.
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