Engine construction

Textron Lycoming IO-360-L2A engine is direct drive, four cylinder, fuel injected, horizontally opposed, and air cooled. The cylinders, numbered from front to rear, are staggered to have individual throws on the crankshaft for each connecting rod. The right front cylinder is number 1 and cylinders on the right side of the engine are identified by odd numbers 1 and 3. The left front cylinder is number 2 and the cylinders on the left side are identified as 2 and 4.

Cylinders –  are of air-cooled construction with the two major parts, head and barrel, screwed and shrunk together. 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. Barrels have deep integral cooling fins and the inside of the barrels are ground and honed to a specified finish.

Valve Operating Mechanism – 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. Valve springs bear against hardened steel seats and are retained on the valve stems by means of split keys.

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 is made from a chr-ni-moly steel forging. Bearing journal surfaces are nitrided.

Connecting Rods  are made in the form of “H” sections from alloy steel forgings. They have replaceable bearing inserts in the crankshaft ends and bronze bushings in the piston ends. Two bolts and nuts through each cap retain the bearing caps on the crankshaft ends.

Pistons  are machined from an aluminum alloy. Piston pin is of 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  is made from an aluminum casting and is fastened to the rear of the crankcase and the top rear of the sump. If forms a housing for the oil pump and the various accessory drives.

Oil Sump  incorporates an oil drain plug, oil suction screen, mounting pad for carburetor or fuel injector, the intake riser and intake pipe connections.

Crankcase Covers  are employed on the top and bottom of the engine. These covers incorporate oil suction screens, oil scavenge line connections. The top cover incorporates a connection for a breather line and the lower cover a connection for an oil suction line.

Cooling System –  cooled by air pressure. Baffles are provided to build up a pressure and force the air through the cylinder fins. The air is then exhausted to the atmosphere through gills or augmentor tubes usually located at the rear of the cowling.

Induction System –  distribution of the fuel-air mixture to each cylinder is obtained through the center zone induction system, which is integral with the oil sump and is submerged in oil, insuring a more uniform vaporization of fuel and aiding in cooling the oil in the sump. From the riser the fuel-air mixture is distributed to each cylinder by individual intake pipes.