A Retired Book Keeper's Hobby - Amazing Craftsman

[Cmar]

Also notice the heads are inverted, with intake manifold at the bottom and the headers rising from the typical "intake valley" between the heads of as V style engine! Such a tight fit for the headers. Some serious out of the box thinking going on. Also note the headers grouped in sets of 3. Two V6s back to back to make the V12.

After seeing this engine I did a little research to see if there were any examples of mix match technologies leveraging common parts that made inline and V engine configurations, Sure enough I found a nice example from Detroit Diesel Engines. Here's part of my correspondence to my father in law:

Thanks for the note and further explanation. I had missed the twin V6 engine angle. I was too distracted looking and analyzing the top of the engine turbo routing configuration.​

​

I know that Detroit Diesel built the Series 71, (a 2 stroke engine that came) in multiple configurations, both inline and V! Inlines were 1,2,3,4, and 6 cylinders. V configurations were 6, 8, 12, 16, and 24 cylinders. Heads were designed to be swapped among different configurations. for instance, the V-24 used 4 heads from the inline 6 engine. Doing so kept costs, and weight down. Detroit Diesel even made a few models in an opposing cylinder pancake configuration, ala Subaru or the Corvair engine designs. ​

​

The inlines were first produced in 1938 and were used in all manner of equipment, tanks, landing craft, and heavy equipment. The US Military used a ton of them. The bigger V configurations were also used in all manner of products, like buses. motor homes, trucks, fire engines, tractors and even small commercial fishing/shrimp boats, as well as yachts, and electric generators. ​

​

The V's came out in 1957. Production stopped in 1995 when the 4 stroke diesel replaced it. ​

​

I think it strange that the 71 series was considered normally aspirated, but it came with a turbo. It was also produced in left hand and right hand configurations, (clockwise and counter - clockwise rotations). Which was great for twin engine boat applications, and front engine vs rear engine applications (think Greyhound buses and Caterpillar road graders).​

​

The S-71 was a clever modular design that proved itself, staying in production for over 57 years! Engineering at its finest!​

That's because diesel two strokes require a super charger to work, they need it to charge the cylinder and scavenge the exhaust, it's not a performance aid per se, it is an integral part of the engine design. That function is performed by crankcase compression in a normal two stroke like a mower, motorcycle, or whipper snipper.

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[5thranger]

That's because diesel two strokes require a super charger to work, they need it to charge the cylinder and scavenge the exhaust, it's not a performance aid per se, it is an integral part of the engine design. That function is performed by crankcase compression in a normal two stroke like a mower, motorcycle, or whipper snipper.

Correct, use to work on a fleet of International semi-trucks with 8V-71 engines. Had a driver dump clutch and had engine running backwards and exhaust started going out air cleaner. Back in the early 1980s.

 

[Chris M]

Correct, use to work on a fleet of International semi-trucks with 8V-71 engines. Had a driver dump clutch and had engine running backwards and exhaust started going out air cleaner. Back in the early 1980s.

Back in 1988 when I was in truck driving school our instructors mentioned that such a thing could happen in the engines of the day.
Thankfully I never made that happen!

 

[TJC]

That's because diesel two strokes require a super charger to work, they need it to charge the cylinder and scavenge the exhaust, it's not a performance aid per se, it is an integral part of the engine design. That function is performed by crankcase compression in a normal two stroke like a mower, motorcycle, or whipper snipper.

Thanks for the explanation! Makes sense.

 

[TJC]

Correct, use to work on a fleet of International semi-trucks with 8V-71 engines. Had a driver dump clutch and had engine running backwards and exhaust started going out air cleaner. Back in the early 1980s.

That is a great story!

 

[5thranger]

That is a great story!

It was a 2 stroke Detroit Diesel 8V-71

 

[rang19ca]

Also notice the heads are inverted, with intake manifold at the bottom and the headers rising from the typical "intake valley" between the heads of as V style engine! Such a tight fit for the headers. Some serious out of the box thinking going on. Also note the headers grouped in sets of 3. Two V6s back to back to make the V12.

After seeing this engine I did a little research to see if there were any examples of mix match technologies leveraging common parts that made inline and V engine configurations, Sure enough I found a nice example from Detroit Diesel Engines. Here's part of my correspondence to my father in law:

Thanks for the note and further explanation. I had missed the twin V6 engine angle. I was too distracted looking and analyzing the top of the engine turbo routing configuration.​

​

I know that Detroit Diesel built the Series 71, (a 2 stroke engine that came) in multiple configurations, both inline and V! Inlines were 1,2,3,4, and 6 cylinders. V configurations were 6, 8, 12, 16, and 24 cylinders. Heads were designed to be swapped among different configurations. for instance, the V-24 used 4 heads from the inline 6 engine. Doing so kept costs, and weight down. Detroit Diesel even made a few models in an opposing cylinder pancake configuration, ala Subaru or the Corvair engine designs. ​

​

The inlines were first produced in 1938 and were used in all manner of equipment, tanks, landing craft, and heavy equipment. The US Military used a ton of them. The bigger V configurations were also used in all manner of products, like buses. motor homes, trucks, fire engines, tractors and even small commercial fishing/shrimp boats, as well as yachts, and electric generators. ​

​

The V's came out in 1957. Production stopped in 1995 when the 4 stroke diesel replaced it. ​

​

I think it strange that the 71 series was considered normally aspirated, but it came with a turbo. It was also produced in left hand and right hand configurations, (clockwise and counter - clockwise rotations). Which was great for twin engine boat applications, and front engine vs rear engine applications (think Greyhound buses and Caterpillar road graders).​

​

The S-71 was a clever modular design that proved itself, staying in production for over 57 years! Engineering at its finest!​

While in the US Army I was a track mechanic. We had quite a few normally aspirated 6V-71, and 8V-71 engines that we worked on. Later as a Transit bus mechanic, I worked on 6V-71 and 8V-71 turbo after cooled engines. These were all 2 cycle engines. They all screamed like they were going to explode, but rarely ever did. Old school technology for sure.

 

[Cmar]

While in the US Army I was a track mechanic. We had quite a few normally aspirated 6V-71, and 8V-71 engines that we worked on. Later as a Transit bus mechanic, I worked on 6V-71 and 8V-71 turbo after cooled engines. These were all 2 cycle engines. They all screamed like they were going to explode, but rarely ever did. Old school technology for sure.

Yep nothing like the sound of a Detroit Diesel V8 or V12 two stroke diesel whipped up to full noise. They were popular here in interstate buses and Semi's, and boats as well, in the 60's and 70's.
My father was marine engineer for a company over here which used to build aluminum pleasure cruisers. I remember him telling me how one that they built used twin V16 Detroit 2 strokes, and at full throttle that massive 115 foot cruiser would almost plane, and consume 44 imperial gallons per hour each engine. He said is was impossible to enter the engine room without earmuffs.

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