Lycoming TIO-540-A1A, Руководство оператора

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LYCOMING OPERATOR’S MANUAL SECTION 1
TIO-540 SERIES – ANGLE VALVE CYLINDER HEADS DESCRIPTION
SECTION 1
DESCRIPTION
The TIO-540 series listed in this manual are six cylinder, direct drive, horizontally opposed, fuel injected,
turbocharged, air cooled engines with angle head valves.
In referring to the location of the various engine components, the parts are described in their relationship
to the engine as installed in the airframe. Thus, the power take-off end is considered the front and the
accessory drive end the rear. The sump section is considered the bottom and the opposite side of the engine
where the shroud tubes are located the top. Reference to the left and right side is made with the observer
facing the rear of the engine. The cylinders are numbered from front to rear, odd numbers on the right, even
numbers on the left. The direction of rotation for accessory drives is determined with the observer facing the
drive pad.
Cylinders
– The cylinders are of conventi onal air-cooled construction with the two major parts, head and
barrel, screwed and shrunk together. The heads are made from an aluminum alloy casting with a fully
machined combustion chamber. Rocker shaft bearing supports are cast integral with the head along with
housings to form the rocker boxes for both valve rockers. The cylinder barrels, which are machined from
chrome nickel molybdenum steel forgings, have deep integral cooling fins and the inside of the barrels are
ground and honed to a specified finish.
Valve Operating Mechanism –
A conventional type camshaft is located above and parallel to the crankshaft.
The camshaft actuates hydraulic tappets which operate the valves through push rods and valve rockers. The
valve rockers are supported on full floating steel shafts. The valve springs bear against hardened steel seats
and are retained on the valve stems by means of split keys.
Crankcase –
The crankcase assembly consists of two reinforced aluminum alloy castings, fastened together
by means of studs, bolts and nuts. The mating surfaces of the two castings are joined without the use of a
gasket, and the main bearing bores are machined for use of precision type main bearing inserts.
Crankshaft
– The crankshaft is made from a chrome nick el molybdenum steel forging. All bearing journal
surfaces are nitrided. Freedom from torsional vibration is assured by a system of pendulum type dynamic
counterweights.
Connecting Rods
– The connecting rods are made in the form of “H” section from alloy steel forgings. They
have replaceable bearing inserts in the crankshaft ends and bronze bushings in the piston ends. The bearing
caps on the crankshaft ends are retained by two bolts and nuts through each cap.
Pistons
– The pistons are machined from an aluminum all oy forging. The piston pin is a full floating type
with a plug located in each end of the pin. Depending on the cylinder assembly, pistons may be machined
for either three or four rings and may employ either half wedge or full wedge rings. Consult the latest
revision of Service Instruction No. 1037 for proper piston and ring combinations.
Accessory Housing
– The accessory housing is made from an aluminum casting and is fastened to the rear of
the crankcase and the top rear of the sump. It forms a housing for the oil pump and the various accessory
drives.
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