Internal combustion engines called straight or inline Caterpillar C18 have a single row of cylinders. They frequently have four, six, and eight cylinder arrangements. The simplicity of these engines as compared to horizontally opposed or even V designs is a significant advantage. They can mill their crankshaft and cylinder banks from the same metal casting. The arrangement uses fewer cylinder heads and camshafts. Since straight engines are frequently compact, they can be installed in any direction. The majority of the engine’s parts and accessories can be accessed from the side rather than the top or bottom of the cylinder banks, making maintenance significantly simpler. Caterpillar C18

The simplest engine plan that has both primary and secondary mechanical engine balance and does so without a balancing shaft is the straight-six or I-6 arrangement. Compared to engines with fewer cylinders, it has significantly less vibration.

The front and rear trio of cylinders are mirrored to prevent vibration. The pistons travel on distinct strokes of a whole 4-stroke cycle and are intended to move in pairs, but they do so 360 degrees out of phase. The likelihood of polar rocking motions is therefore eliminated. Its three planes of arrangement for its six crank throws are offset by 120 degrees. In this manner, the total secondary forces brought about by variations in sinusoidal motion are zero. A carefully thought-out vibration damper is also included in the Caterpillar C18, which aids in absorbing torsional vibration. Caterpillar C18