6v71 detroit diesel engine

The Legendary 6V71 Detroit Diesel Engine

The 6V71 is a two-stroke diesel engine manufactured by Detroit Diesel, known for its robust design and distinctive sound. This engine, part of the “71 Series,” was widely used in various applications, from buses and trucks to boats and industrial equipment. Its relatively simple mechanics made it a popular choice for its time.

What is the 6V71?

The “6V71” designation breaks down as follows: “6” indicates the number of cylinders (six), “V” denotes the engine’s V configuration, and “71” refers to the cubic inch displacement per cylinder. This results in a total displacement of 426 cubic inches (approximately 7.0 liters). The 6V71, like other Detroit Diesel engines of its era, is a two-stroke engine, meaning it completes a power cycle in one revolution of the crankshaft, unlike the more common four-stroke engine.

Key Features and Characteristics

Several aspects define the 6V71:

Two-Stroke Operation

Unlike four-stroke engines, the 6V71 uses a blower (a type of supercharger) to scavenge exhaust gases and fill the cylinders with fresh air. This results in a quicker power stroke but can also lead to higher fuel consumption compared to four-stroke engines.

Unit Injectors

Each cylinder has its own individual fuel injector, mechanically operated by the engine’s camshaft. This system delivers precise fuel metering and contributes to the engine’s responsiveness. More information about the Detroit Diesel Series 71 can be found on Wikipedia.

Reliability and Maintainability

The 6V71 is known for its robust construction and relatively simple design. This made it a popular choice for applications where reliability and ease of maintenance were crucial. Its parts were also widely available, further contributing to its longevity.

Distinctive Sound

The 6V71 engine has a unique and recognizable sound, often described as a “screaming” or “whistling” noise due to the blower and the two-stroke combustion cycle. This sound has become iconic in the world of diesel engines.

Common Applications

The 6V71 found widespread use in:

• Buses: City buses were a common application for the 6V71, especially in the mid-20th century.
• Trucks: Various trucks and heavy-duty vehicles utilized the engine.
• Boats: Marine versions of the 6V71 powered boats and yachts.
• Industrial Equipment: Generators, pumps, and other industrial machinery often employed the 6V71.

FAQs

Why is the 6V71 called a “two-stroke” engine?

It completes a power cycle in one revolution of the crankshaft, using a blower to scavenge exhaust and fill the cylinders.

What kind of fuel does the 6V71 engine use?

It uses diesel fuel, as it is a diesel engine.

What is the displacement of a 6V71 engine?

The displacement is approximately 426 cubic inches (7.0 liters).

What makes the 6V71 engine so loud?

The blower and the two-stroke combustion cycle contribute to its distinctive and loud sound.

Are 6V71 engines still in production?

No, the 6V71 is no longer in production, but many are still in use, and parts are often available.

Summary

The 6V71 Detroit Diesel engine is a legendary engine known for its two-stroke operation, robust design, and distinctive sound. While no longer in production, its impact on various industries and its enduring popularity among engine enthusiasts cement its place in diesel engine history. Its reliability and maintainability made it a staple in buses, trucks, boats, and industrial equipment for many years.