ronbros

A 2 stroke diesel is probably the ultimate piston engine, it comes in many forms, an engines effeciency is determined buy its power to weight ratio, weight any where is the enemy, it allows more weight to be moved ,which should be the purpose of any engine. the ultimate hi-speed diesel, was built by JUMO engines. quick think, what does your engine weigh in lbs. and what is the HP. back in WW2 Jumo had diesels that weighed 1400lbs and put out 1200HP continuosly! try that with any diesel that you know of, and they where 2strokes opposed piston, not to be confused with opposed cylinders(like Porsche,etc), even the wonderful Audi V12 race car has a job to match those incredable JUMOs, some one has to stepup and manufacture some modern tech electronic 2stroke opposed piston units. Thx Ron

DiezelSmoke

The marine models have a return fuel, they have too, to provide cooling to the injector and lubrication. I primarly worked on 60' or less and they all had it. DD made a military model with an aluminium block, these are very light weight engines.

Diesel_Storm

That is a chain saw engine compared to this:

http://people.bath.ac.uk/ccsshb/12cyl/

The cylinder bore is just under 38" and the stroke is just over 98". Each cylinder displaces 111,143 cubic inches (1820 liters) and produces 7780 horsepower. Total displacement comes out to 1,556,002 cubic inches (25,480 liters) for the fourteen cylinder version.

Some facts on the 14 cylinder version:

Total engine weight:2300 tons (The crankshaft alone weighs 300 tons.)
Length: 89 feet
Height: 44 feet
Maximum power: 108,920 hp at 102 rpm
Maximum torque: 5,608,312 lb/ft at 102rpm

Raspy

I was on a Coast Guard 311 Cutter with 4 F-M 10 cyl opposed piston engines. I was in the front engine room with two of them. I can remember checking the rod bearing wear by inserting a piece of 1/4 inch lead rod into the injector hole and rolling the engine over. The two pistons would come together and smash the lead, then we'd measure it's thickness. Once we had a lot of gear noise from the the verticle shaft area and pulled the upper crank while out at sea. Then a bad storm hit and we only had one prop shaft operable. The boat had a single rudder and soon we couldn't steer because the sea was so rough. The boat was rolling to 55 degrees and we had the upper crank out and lashed to 4X6s laid between the two engines. Finally the captain ordered down to get the other engine and our prop shaft on line regardless. It was a problem because it was so dangerous down there and the two engines cooling and other systems were all interconnected. We scrambled around getting pipes capped and plugged etc and every once in a while the OD would pipe over the loud speaker "all hands stand by for heavy rolls!". We'd grab ahold and you could hear tools and equipment crashing as she rolled. It was exciting! Good times. The final thing was that our relief ship came out with parts and we had to high line them across at sea. We were about 1000 miles off the east coast and at the time I didn't think something like that was possible.

ronbros

Like i said, HP to engine weight. makes more effeicent engines, at least an engine most of us could use for hiway transportation. this topic has gotten a little off topic! Its like a Nuclear sub, Trident comes to mind, how many guys take there family for a sunday afternoon ride, not a practable idea! if we want silly and save fuel, do away with all personal transportation. THX RON

johnh

if i remember right, all the greyhound busses had DD 6-71' s in them...there was a lot of conversions to motor homes when greyhound got rid of them

Red3quarter

The ones I work on are mostly 645E 16 and 12 cyl engines, some are 567C with 645 powerpacks in them most of them are 12 cyl with a couple 8s, and then we have a couple 567AB blocks running around. No 710s in any of our locos we don't run high enough speed or haul heavy enough to utilize the big turbo engines. Most of our locos are SD38-2 & 3's and sw1200's. We have a few sw1001's,NW2,SW1500,GP38-2, and a few leased SD40M-3 (Former SD45's that had the turbo 20 cyl replaced with a turbo 16 cyl)

What impresses me about these engines is that how forgiving and durable they are. Our crews beat the snot out of them and they hold up pretty well.

ronbros

johnh! I did own aGMC Greyhound,converted to motorhome, DD 6-71 power. it got 10mpg at 70mph,my newer 2003 cummins 8.3, only gets 7.5-8mpg, yes it will go up the hills faster, but at cost of fuel id settle for more mpg, and do it a little slower. what has been lost in the 50yrs of engine technology.?? they used to say the old DD 2stroke was bad on fuel ,cant prove it by me!! that old DD had mechanical unit injectors,$50. a piece exchange, cylinder kits 125.each, full set of baerings 150.. MAN! have times changed. Thx Ron

Haulin_in_Dixie

I never got over 4 mpg out of my 238, uphill, downhill, cold, hot, empty, loaded, did not matter.... 4 mpg.

318 was four also, 6v92tt was 5 1/2 to 6 mpg. 12v71, well easy throttle light load 5, get on it in the mountains and I was lucky to get 3. A local trucking company had a few glider KW's built with 12v92t and they claimed to get 5 and I can attest that they were the fastest thing on the road. I was empty climbing El Cahon with the 6v92, one passed me, he was doing at least 70 with a full load of cast iron pipe.

GMC coaches were 318 (8v71) after about 1970, the Silver Eagle busses (Trailways) were 318 also. The original Sceni Cruisers (1955) were twin engine but after a year or so they were 318.

ronbros

my GMC was a 1948, model 3751, 220hp, GMC 6-71 and it got on a flat cruise 9-11mpg, just what the manual said. sold it to a movie company. maybe you were trying to keep up with everyone and runnin FULL rack all the time along with big injectors. 6-71s were only 7 liters. Thx Ron

GasganoFJ60

Neat little Detroit 2-Stroke video I came across....

wannadiesel

Never gotta worry about somebody borrowing a truck like that - only an old-school truck driver could get it out of the driveway.

Haulin_in_Dixie

yes yes and yes. I could wear out a set of liners in 100,000. Took about $600 and a Saturday afternoon to put them in. Test drove on Sunday and loaded on Monday. Throttle had two positions, slow idle and fast idle. Governor set to 2500, 13 speed, tag axle, 444 rear, gross flat bed loads, 48 states mostly west.

rip 112

this is a screamer!

NoSeeUm

Nuclear powered Cold War submarines had a diesel similiar to this one. About 400KW as I recall. I am not sure what they have these days, that was 25 years ago for me. I do remember that if the snorkel got submerged while dieseling it would feel like your ear drums got sucked into some where to the vicinity of your tonsels.

Jim