To fully appreciate the value of an aircraft cylinder overhaul, it helps to understand the anatomy of an aircraft cylinder and how each of its components function.

In general, an aircraft cylinder is where the power in the aircraft engine is initiated. The cylinder provides a combustion chamber and it houses the piston (which transfers the force created by expanding gas to the crankshaft) and connecting rod (which connects the piston to the crankshaft, affecting overall balance and efficiency). Aircraft cylinders need to be light enough to keep engine weight optimal, strong enough to withstand high temperatures and the strain of normal engine operation, as well as maintain efficient heat conducting and cooling properties.

Aircraft cylinders are comprised of two main parts, the cylinder head and the cylinder barrel: 

The Cylinder Head

As the portion of the aircraft cylinder where the combustion of the fuel-air mix takes place, the cylinder head provides heat conductivity and adequate cooling. Typically, in an air-cooled aircraft engine, the cylinder head is made from aluminum which is an excellent heat conductor that is also lightweight. For strength, cylinder heads are die-cast or forged. The cylinder head’s inner semi-spherical shape adds even more strength. Spark plus bushings, valve guides, rocker arm bushings and valve seats are all installed within the cylinder head once it has been cast. 

The Cylinder Barrel

When assembled, the aircraft cylinder head is expanded by heating and screwed down on a cooled aircraft cylinder barrel. When the cylinder head cools and the barrel warms back up, this results in a tight, gas leak-free connection.

The aircraft cylinder barrel also needs to be as lightweight as possible while being capable of handling high temperatures. Some cylinder barrels are smaller in diameter or choked at the top to allow for more optimal heat expansion. Since it is the place housing all the piston action, the cylinder barrel must also be constructed of strong material – usually steel forged with a hardened inner surface to resist wear from the piston and piston rings. As it does wear, an aircraft cylinder barrel may be repaired by chroming and honing cylinder walls can restore its proper dimensions.

Other components essential to the proper function of the aircraft cylinder include:

Spark Plugs 

The spark plugs are tasked with igniting the air-fueled mix within the combustion chamber. Spark plug openings are fitted with bushings that are screwed in after shrinking.

Valves, Valve Guides and Valve Seats

Valves control air flow and exhaust gasses. More specifically, intake valves allow the fresh air-fuel mix to enter the cylinder and the exhaust valve expels burned gas. Valve guides, which provide guides for valve stems, are shrunk and screwed into drilled openings within the cylinder head. Valve seats are rings made from hardened metal that protect the cylinder head from exhaust gasses and valve action.

Rocker Arm

The aircraft rocker arm is basically a fulcrum-style leverage device which allows fuel and air to be drawn into the combustion chamber during the intake stroke and exhaust gasses to be expelled during the exhaust stroke.

Cylinder Gaskets and Seals 

These aircraft cylinder components prevent leaks between the head and the barrel and help to ensure that proper lubrication takes place.

Fins

The cylinder heads of air-cooled aircraft engines are subjected to extreme temperatures. External fins in air-cooled cylinders dispel heat during combustion. Additionally, the aluminum alloy used in the construction of the cylinder head is ideal for machining deep and closely spaced fins, and more resistant than most metals to the corrosive nature of the elements within gasoline.

Pistons

Pistons in an aircraft engine serve to transfer the force created by expanding gas to the crankshaft via a piston rod – also called a connecting rod. Essentially, a fuel-air mix is ignited by spark and as it burns, enabling the piston to act as a moving wall within the combustion chamber. As the charge is ignited and it draws the fuel-air mixture, the piston moves down the cylinder. This is referred to as the power stroke. The piston then compresses the charge as it moves upward toward the top center, which is the compression stroke.

An Aircraft Cylinder Specialist You Can Trust

Aircraft cylinders and their proper performance are a crucial part of safe and efficient flights. That is why it is important to trust yours to an experienced, reputable aircraft cylinder overhaul specialist, such as Moore Performance Products. 

A very specific skill set is required for proper aircraft cylinder maintenance and overhauls. For over 30 years, the professional aircraft cylinder overhaul specialists at Moore Performance Products have expertly served the aviation industry. The Moore Performance Products aircraft service professionals provide a variety of overhaul services nationwide and overseas for the aircraft and aerospace industries and are uniquely qualified with aircraft cylinder repair knowledge and experience to take the proper steps for your aircraft cylinder repair.

It is also important to use a properly qualified FAA-certified repair station with highly ranked, experienced personnel possessing an innate knowledge of everything from the most general, to the most minor details of FAA regulation compliance. Only an FAA-certified mechanic may overhaul aircraft cylinders and return an aircraft to service once FAA aircraft airworthiness standards are met. Moore Performance is an FAA-certified repair station.

You can reach Moore Performance Products, which is conveniently located at 132 W. Park Avenue in Edgewater Florida, by calling 386-409-7501 or 888-409-7555 anytime between 9 a.m. and 5 p.m. Monday through Friday.