When I think of two-stroke engines, I generally think of either lawn maintenance equipment or dirt bikes, and pretty much the last thing that comes to mind is a massive 16-cylinder 5,000-pound diesel engine meant to propel a giant semi across the country.
Except that's exactly what Detroit Diesel built when it created its 16V71 two-stroke diesel engine, and thankfully Rich from the YouTube channel Deboss Garage got a junkyard example to tear down and demystify for us.
A 16-cylinder two-stroke diesel sounds like kind of a weird engine -- and it is -- but they weren't entirely uncommon in their day, thanks to their ability to produce vast amounts of power and torque. Ultimately, as is the case with other two-stroke engine applications, tightening emissions regulations killed them off.
The Detroit Diesel 71-series engine was built from the mid-1930s through the mid-1990s in configurations ranging from an inline-four-cylinder all the way up to a V24. The 71-series was modular too, so a 16-cylinder model used four inline-four cylinder heads and two V8 blocks bolted together. The engines were also capable of running clockwise or counterclockwise with only a change of starter.
Rich's explanation is fantastic and shows just how unique, ingenious and seriously robust these engines were in their heyday, and it's definitely worth kicking back for a half-hour with a cup of coffee to check it out.