Diesel Two Stroke
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If you have answers, please help by responding to the unanswered posts.
Lepke
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3-53 is about 73 hp, I've never seen a 2-53. I don't think the 53s had the same range of cylinder options as the 71s.
My current natural IL671s were built in 1947 and rebuilt once by me about 10 years ago. Exact hours unknown, but 10s of thousands. They'll be looking at a rebuild about 50 years from now. I don't think the average yacht engine of today can match that.
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Well if you’re as crazy about engines as about anchors, then go search out an old DD 1-71, give it a nice overhaul and motor off into the sunset!
rslifkin
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Very true, most won't match that. But for how most boats are used, they don't need to. When you start out with that kind of lifespan, it's almost a no-brainer to give up a little lifespan to save a bunch of weight (relative to power output). As most people still won't manage to wear the thing out.
FF
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You base your condemnation of the DD's noise based on that ???"
The Jimmy exhaust is fairly loud , when used with a poor muffler system.
Install a "hospital critical" muffler unit and its as loud as a new Buick.
Lighter weight units are aluminum blocks that were found in mine sweepers.
The Jimmy exhaust is fairly loud , when used with a poor muffler system.
Install a "hospital critical" muffler unit and its as loud as a new Buick.
Lighter weight units are aluminum blocks that were found in mine sweepers.
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pacopico
Veteran Member
Back to my EMD reference, on a Tier III (EUI) 16-710G7C rated at 4000BHP/900RPM continuous BSFC is .325 LB/HP-Hr. Assuming 7.1Lb/gal for fuel that gets you to 183GPH, or 21.8 hp/gal.
2-cycle, uniflow scavenged, using a gear-driven centrifugal supercharger/turbocharger with an overrunning clutch.
On the Jimmy subject, they did make 2-53's for industrial applications...I have never seen one in a boat.
I have a data book that calls out a 2-71 power unit at 48 HP/1800RPM, I would assume the 2-53 to be mid thirties on HP.
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Nomad Willy
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Ye godds they made a one cylinder DD?
Never would’a thunk.
I was on the boat Monday running it at the floats and thinking how smooth it is.
Yes Ted the 3-71 should be smooth w a big flywheel and as many power strokes as a typical 6 cylinder engine.
Yes Mako I do like engines and had a good time w many. UL aircraft, outboards (got 4 in the garage, cars and many motorcycles.
And the replies here have just extended my engine life.
Never would’a thunk.
I was on the boat Monday running it at the floats and thinking how smooth it is.
Yes Ted the 3-71 should be smooth w a big flywheel and as many power strokes as a typical 6 cylinder engine.
Yes Mako I do like engines and had a good time w many. UL aircraft, outboards (got 4 in the garage, cars and many motorcycles.
And the replies here have just extended my engine life.
Ski in NC
Technical Guru
DD's can get real close to the 20hp/gph benchmark if they are set up for it. Cam timing, injector size, compression ratio, and maybe modest turbo. Then run in their sweet spot, usually 1200-1600rpm.
Where their numbers are in the 16-17hp/gph is the high rated versions with lots of turbo and big injectors.
Interesting to read about the origin of these things. Alexander Winton in Cleveland built bicycles and then automobiles, got interested in engines. Started developing a variety of gas and diesel four strokes, then really focused on the two stroke diesel with the intent of powering locomotives. Had some very promising engines in development and in production.
In the mid (??) 1930's was bought out by GM. GM continued with development. The EMD came out with 567. Cleveland made the 278 that powered many subs in ww2. Then in the late 30's the little 71 for landing craft, etc. I think GM developed the 71, but the EMD and Cleveland were mostly Winton designs refined by GM.
The 53 came out in the 1950's, the 92 (basically a slightly larger bore than 71, different liner (wet) came out in the 1970's.
I have rebuilt some of these in my shop. The engine block casting is rather complicated and very well made. Really humbling to look at how they are made by having all of it apart.
Where their numbers are in the 16-17hp/gph is the high rated versions with lots of turbo and big injectors.
Interesting to read about the origin of these things. Alexander Winton in Cleveland built bicycles and then automobiles, got interested in engines. Started developing a variety of gas and diesel four strokes, then really focused on the two stroke diesel with the intent of powering locomotives. Had some very promising engines in development and in production.
In the mid (??) 1930's was bought out by GM. GM continued with development. The EMD came out with 567. Cleveland made the 278 that powered many subs in ww2. Then in the late 30's the little 71 for landing craft, etc. I think GM developed the 71, but the EMD and Cleveland were mostly Winton designs refined by GM.
The 53 came out in the 1950's, the 92 (basically a slightly larger bore than 71, different liner (wet) came out in the 1970's.
I have rebuilt some of these in my shop. The engine block casting is rather complicated and very well made. Really humbling to look at how they are made by having all of it apart.
I had two of them. Apparently they were destined as gensets onboard minesweepers. I prefer the iron blocks actually although I have to admit that they were quite clean of the typical rust you see. I had internal electrolytic corrosion issues on mine due to neglect by previous owners.
Reducing noise. Definitely a high grade muffler like you state.
Also need to reduce the noise coming from the engine. Three big sources are the air intake, blower and injectors. Basically adding sound suppressing blankets around the air filter, blower and the valve cover.
Island Cessna
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I worked around a mid 1950’s tug having a 6-110 engine with a centrifugal blower, not the roots type on virtually all other GM 2 strokes. The 2 stroke bark was replaced by a pleasant, soft whistling noise. A similar newer tug had the same 6-110 with the roots blower, and the familiar bark, though its 1300 top rpm softened it. It’s too bad the centrifugal blower was short lived, and to my knowledge only used in a few early 110 series. If it had carried on the DD 2 strokes might only be infamous for leaking, not the noise!
Ski will be the expert, but my observation says the leaking can be stopped with modern gasket and seal material, and attention while assembling. In the gentler days of these engine’s youth leaking was less frowned on.
The tug is called the Fosthall, and is still in the Canadian registry, home ported in Masset. If anyone has seen her I’d love an update.
Bill
sbman
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They really should not leak much. Later versions have a better valve cover which helps. If properly put together with copper crush washers under bolts they don't leak much at all, assuming they are healthy. Many engines have been worked on by those not familiar with them and have replaced copper crush washers with split steel lock washers which causes leaks. I found a bunch of these when I rebuilt mine.
They can also leak from the air box drains when oil gets into the Airbox from worn seals or stuck lower piston rings which of course requires service to repair, if it's leaking oil from the airbox drains, there's an issue that needs to be corrected.
Lepke
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I had a 1-71 10kw generator in a tug. 1200 rpm, built in WWII or before. It had compression release and a huge cast iron flywheel you bar'ed over to start it. Fuel usage was about 5gl/24hours depending on the load. I wish I still had it.
You can still buy 6-110 parts from: https://www.wwwilliams.com
The engine was used in the oil industry. Williams bought the rights, molds, patterns, etc. I think the hp was about equal to the 12v71 natural. Sometimes used parts and rarely whole 6-110 engines can be found at:
https://www.surplusman.com/
Detroits properly rebuilt and cared for don't leak with the seals made after WWII.
You can still buy 6-110 parts from: https://www.wwwilliams.com
The engine was used in the oil industry. Williams bought the rights, molds, patterns, etc. I think the hp was about equal to the 12v71 natural. Sometimes used parts and rarely whole 6-110 engines can be found at:
https://www.surplusman.com/
Detroits properly rebuilt and cared for don't leak with the seals made after WWII.
Nomad Willy
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My father had a 103’ X 21’6”.
Had a GM 268a straight eight. 268 cu.in. Per cyl.
500hp w the blower (roots) on the front end of the engine.
The boat was a Navy WWII “baby freighter”.
Wish I had a picture.
Had a GM 268a straight eight. 268 cu.in. Per cyl.
500hp w the blower (roots) on the front end of the engine.
The boat was a Navy WWII “baby freighter”.
Wish I had a picture.
Bill V
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My 6 years in the Navy operating small craft in some far away places never saw anything but DD engines in them. 6-71's. 6V53's & 8V71's. I've seen and run twin 6V53's at 3100 for a solid hour transporting wounded Marines to a medivac. Many Navy and Marine personnel owe their lives to the strength of those "double breasted Yamaha's".
Lepke
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I owned an ex-navy YTM with 2 GM 8-268As running propulsion generators (diesel electric). The generators were 250v DC and also could also supply ships power. Everything except nav equipment was 250vdc. The generators had windings that allowed a 250v battery bank to start the main engines. Towing used 50-75 gallons an hour.
I had a 2nd tug that was diesel direct with a single air starting v16-268A.
Both had Detroit auxiliary generators. But the diesel electric didn't need the Detroit running if the mains were on. Probably thousands of GM 268As were built in WWII.
The tugs also had fire monitors. Big nozzles that could direct 1000 gallons/minute of water or could supply hose hookups. Monitors were fun to play with. Hose down jet skis, etc.
My time in the navy in VN, all the patrol and riverine boats were Detroit powered. Speaking of Detroit reliability, I once had to continue running a 671 that had been hit by an anti-tank round. It would only do about 1000rpm, but it ran.
Ships built in WWII and after usually had a Detroit emergency generator. Some had 3-268As generators. Some destroyers had one of each. I was told it depended on what was available when the ship was built.
I had a 2nd tug that was diesel direct with a single air starting v16-268A.
Both had Detroit auxiliary generators. But the diesel electric didn't need the Detroit running if the mains were on. Probably thousands of GM 268As were built in WWII.
The tugs also had fire monitors. Big nozzles that could direct 1000 gallons/minute of water or could supply hose hookups. Monitors were fun to play with. Hose down jet skis, etc.
My time in the navy in VN, all the patrol and riverine boats were Detroit powered. Speaking of Detroit reliability, I once had to continue running a 671 that had been hit by an anti-tank round. It would only do about 1000rpm, but it ran.
Ships built in WWII and after usually had a Detroit emergency generator. Some had 3-268As generators. Some destroyers had one of each. I was told it depended on what was available when the ship was built.
twistedtree
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If anyone wants a DD fix, check out Bus Grease Monkey on YouTube. It's vintage buses with DD 2 strokes, and he seems to know them really well. I've never owned or worked on a DD, but learned a lot from watching. It's all from a time gone by with lots of massive cast/machined parts. Gotta love it, even though I'd never want one.
Interestingly, even with current emissions requirements, unit injectors are still used on some modern 4 strokes like my Scania 13 liter. The Detroit Series 60 4 strokes used them too.
Interestingly, even with current emissions requirements, unit injectors are still used on some modern 4 strokes like my Scania 13 liter. The Detroit Series 60 4 strokes used them too.
Nomad Willy
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FF had or has a bus/motor home w some kind of DD.
FF
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So far I have has an 8v71 in a GM 4106 , a 6-71 in our 50 ft Navy utility launch , a 3208 tossed for a DD Ser 50 in out Flxible bus conversion.
The inline natural 6-71 ran 50-60 hours before the lube oil would show any color , 100-125 to change.
Was hard mounted , very smooth keel cooled dry stack so was really easy to maintain . A great feature was the ease, -1 bolt- to remove, an air box cover so preping for 6 months of non use was just a few squirts of storage oil .
ATF as engine fuel kept the injectors from seizing during storage .
A grand engine for a lazy fellow!
The inline natural 6-71 ran 50-60 hours before the lube oil would show any color , 100-125 to change.
Was hard mounted , very smooth keel cooled dry stack so was really easy to maintain . A great feature was the ease, -1 bolt- to remove, an air box cover so preping for 6 months of non use was just a few squirts of storage oil .
ATF as engine fuel kept the injectors from seizing during storage .
A grand engine for a lazy fellow!
Benthic2
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Nomad Willy
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I was home ported in Masett in the 70’s.
Masett’s a long way from Boston.
Masett’s a long way from Boston.
Ski in NC
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Just a trivia tidbit:
The Cleveland 268 and 278 did not follow GM's convention of naming after the cubic inches per cylinder. They followed Winton's model number scheme which had more to do with some sort of series based on when it was introduced.
268 was 223cu in/cyl, were inline with 3 to 8 cyl. Mostly genset on navy ships/subs.
278 was 631cu in/cyl. V-block in 12 or 16cyl. Mostly submarine propulsion engines.
DD 53, 71, 92, 110, 149 were all cu in/cyl
Same with EMD 567, 645, 710 loco engines. Also used in tugs, etc as prop engines.
Edit: Another tidbit: The Calypso dive boat had Cleveland 8-268 propulsion engines.
The Cleveland 268 and 278 did not follow GM's convention of naming after the cubic inches per cylinder. They followed Winton's model number scheme which had more to do with some sort of series based on when it was introduced.
268 was 223cu in/cyl, were inline with 3 to 8 cyl. Mostly genset on navy ships/subs.
278 was 631cu in/cyl. V-block in 12 or 16cyl. Mostly submarine propulsion engines.
DD 53, 71, 92, 110, 149 were all cu in/cyl
Same with EMD 567, 645, 710 loco engines. Also used in tugs, etc as prop engines.
Edit: Another tidbit: The Calypso dive boat had Cleveland 8-268 propulsion engines.
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Island Cessna
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Yes.
She was built new by John Manley in New Westminster, and worked on the Upper and Lower Arrow Lakes for decades. As I recall her 6-110 was 220 hp.
Bill
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FF
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"As I recall her 6-110 was 220 hp."
A still useful ROT is 3 cubic inches of a normally aspired engine will make 1HP with no strain and have a long life.
110 times 6 = 660 divided buy 3 = 220hp. Sounds about right.
A still useful ROT is 3 cubic inches of a normally aspired engine will make 1HP with no strain and have a long life.
110 times 6 = 660 divided buy 3 = 220hp. Sounds about right.
sunchaser
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Keep these great DD stories coming. I've one on our hobby, pleasure boating.
In 2005 I was smitten by the Tollycrsft 48 design and ride. At that time I was still working and had run across several located at Lake Powell. Rumor had it there was one that had partially sunk at the dock at Page. Couldn't find hide nor hair of it.
About six months later when looking in the Seattle area that sunk boat was found. The owner was recently deceased but had the funds to do a hull strip out and rebuild. It had a gleaming pair of essentially zero hours out of the crate new 6-71s.
According to the broker the engines were the last of that type made for marine applications with top of the line engine electronics presumably making them Tier xx acceptable. Alas the boat was marketed at way too many $$ by the deceased's family wanting to recover invested money.
The T48 with those engines (or Cummins 6bt5.9) was a very economical performer at 18 to 20 knots. I still kick myself for passing on that boat.
In 2005 I was smitten by the Tollycrsft 48 design and ride. At that time I was still working and had run across several located at Lake Powell. Rumor had it there was one that had partially sunk at the dock at Page. Couldn't find hide nor hair of it.
About six months later when looking in the Seattle area that sunk boat was found. The owner was recently deceased but had the funds to do a hull strip out and rebuild. It had a gleaming pair of essentially zero hours out of the crate new 6-71s.
According to the broker the engines were the last of that type made for marine applications with top of the line engine electronics presumably making them Tier xx acceptable. Alas the boat was marketed at way too many $$ by the deceased's family wanting to recover invested money.
The T48 with those engines (or Cummins 6bt5.9) was a very economical performer at 18 to 20 knots. I still kick myself for passing on that boat.
Nomad Willy
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“hide nor hair of it”
You must be from out west .....
You must be from out west .....
healhustler
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Years ago part of my business was the finding, collecting and restoration of vintage heavy trucks, tractors & machinery. I’d guess that the majority of the diesel powered units had original DD 71 or 53 series power plants in some configuration. Most owners expected them to leak oil, accepted it and just enjoyed them for their many other attributes.
It wasn’t until we began doing highly finished restorations that owners really wanted dry Detroit engines. Silicone imbedded in stainless wire cloth became our best friend, even on constant high RPM applications such as sawmills, gensets or fire engines, silicone compression washers & gaskets imbedded in stainless wire cloth pretty well kept the Detroits from blowing their noses over everything else. With the materials available now, there’s no need to put up with a leaking 2 cycle DD in reasonable condition.
It wasn’t until we began doing highly finished restorations that owners really wanted dry Detroit engines. Silicone imbedded in stainless wire cloth became our best friend, even on constant high RPM applications such as sawmills, gensets or fire engines, silicone compression washers & gaskets imbedded in stainless wire cloth pretty well kept the Detroits from blowing their noses over everything else. With the materials available now, there’s no need to put up with a leaking 2 cycle DD in reasonable condition.
Island Cessna
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When most of them were built crankcase venting was a “draft tube” dripping oil under the engine, and rear crankshaft seals were rope. Air box and rocker cover gaskets weren’t going to make much difference!
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