Last year, I picked up several rolls of Navy Microfilm full of engine goodies, two boxes of which were marked as “Alco 16-251A Experimental Submarine Engine”. I pulled them out when I got them, but did not go very far, as it is literally every blueprint sheet to build this engine. Thinking it was just another 251, I put them back in the box.
Last night I dove into them a bit deeper, and naturally the LAST frames on the reels (It looked like a roll of film exploded in the living room) had an elevation drawing. Cool! I devised a way to scan these, although frame by frame on my flatbed. It is a project, but it works. I need to draw up and 3D print some holders to do it more efficiently.
Click the following for larger versions.
After studying the drawing for a second, I noticed the exhaust was not connected to the intake side at all. Wait, 251’s are 4 stroke, and have a turbo…where is the turbo? There is none! That’s a roots blower on the front!
Front mounted on the engine is a blower. The discharge from the blower feeds into a raw water cooled aftercooler before going into the intake side of the engine block.
So, naturally, this raises plenty of questions. I can not find a lick of information about this engine in my usual places, so if anyone has anymore clues as to its history, shoot me a message. I don’t know if this was meant as an emergency generator engine, or propulsion. If anyone wants to build one… I have 600+ plans!
It was sad to hear that this past week, the tug Pegasus made her last trip to the great shipyard in the sky. Figure I would throw together a little post about a cool old vintage tug that would meet an unfortunate end this week.
The Pegasus was built in 1907 by Skinner Shipbuilding in Baltimore, for Standard Oil Company, as the S.O. Co. 16. The tug would later be renamed the Socony 16, and eventually wound up as the Esso Tug #1 after several rounds of company reorganizations. McAllister Towing of New York would purchase the steam powered tug, and rebuild her. Converted to Diesel propulsion, an EMD 567 was installed in place of the large engine and boiler. Now renamed the John E. McAllister, she would join the companies massive fleet doing shipdocking and other harbor work. McAllister would also purchase sister tug Esso Tug #2, and rebuild her the same way, now renamed as the Roderick McAllister. Another Socony sister tug – the Socony #14, would find a new home with Philadelphia’s Independent Pier Company, and was renamed the Jupiter. She also is a museum tug in Philadelphia.
By the 1980’s, towing companies were selling off the last of the older, converted steam tugs. Numerous smaller companies would benefit from this, and would give many of these older tugs a new life. In 1987, the John E. McAllister was purchased by Hepburn Marine Towing of New York, where she was renamed as the Pegasus.
Hepburn Marine would do various work throughout the city, including spending several years towing carfloats for the New York Cross Harbor Railroad. Hepburn would ultimatly charter the tug James E. Witte from Donjon, the former Central Railroad of New Jersey tug Liberty for doing this work – a tug much better suited. Pegasus would be retired in 1997.
The Tug Pegasus Preservation Project was formed, and spent many years actively restoring the tug from the hull up. Volunteers spent several years actively restoring various parts of the tug, and the Pegasus would tow the Lehigh Valley Barge #79 (The Waterfront Museum – see link below) numerous times around the city. I was only ever inside the Pegasus once, a few photos are below.
McAllister would repower the tug with a WWII surplus LST package – a 900HP EMD 12-567ATLP, with a Falk (Falk designed, however several contractors during the war built them, including Esco and Lufkin) reverse-reduction gear. This was one of the most common tug repower packages used after WWII, and I am slowly working on a large post about them.
The engine in the Pegasus was originally installed in Landing Ship Tank (LST) #121, shipped by EMD 6/16/1943. LST 121 was launched August 16, 1943 by Jefferson Boat & Machine. 121 would spend her career on the Pacific front and was present at the Marshall Islands, Iwo Jima, The Marianas, Western Caroline Islands and the Tinian Capture, earning 5 battle stars. She would be sold for scrap in 1946.
The Pegasus project fell dormant, and was looking for new caretakers and leadership for several years. Unfortunately, nothing would come to fruition. The museum ship world is one of the hardest aspects of preservation out there, and it gets harder every year as these boats get older. We have lost numerous preserved tugs just in the last few years. Times are tough, but be sure to help support your favorite museum ship. Every one of these groups needs all the help they can get.
In the days leading up to WWII, the US was beginning to build up the fleets across the board, from Submarines, right down to Tugboats and various auxiliary craft. The Navy came up with a tug design (largely based off of the TAMS Inc. designed tug Thomas E. Moran) for the new fleet of “YT” or “Yard Tug”, which would be used mainly for assisting various warships into dock in ports across the world. Known as the Woban class, the first few tugs would be built at various Naval shipyards on both the East and West coasts. The second batch of tugs was built by Consolidated Shipbuilding, located on the Harlem River in New York City. These Diesel-Electric tugs, built in the Spring of 1940, were powered by twin Alco (McIntosh & Seymour) 539 engines – however I do not know if these were indeed 539’s, or the later model 540 that was introduced during WWII, which used a welded crankcase designed specifically for the Navy. The tugs used Westinghouse electrical gear, and were a rather spartan design.
YT-145Montezuma , the class leader would become a poster boy for Alco, used in several advertisement’s. The second tug, YT-146 Hoga, would become well recognized for her service in Pearl Harbor in the December 7th attack, spending the day as a fireboat as well as pushing burning ships aground.
This design of tug would be built in astounding numbers during the war, being powered by either the above mentioned Alco’s, Cleveland 278/278A engines, or Direct Reversing Enterprise or Fairbanks-Morse engines.
After the war, the Hoga would go on to become the fireboat for the City of Oakland, where she served until the early 1990s. The tug went into the Susian Bay reserve fleet, and was held for preservation for a number of years. In 2005, the tug was donated to the City of North Little Rock Arkansas, and was finally moved their by barge in 2015. While it is great to see her finally preserved, one must question why she would be preserved so far from where she spent her entire career.
Jay Boggess was able to get the photos above of the Hoga at the museum, unfortunately the Hoga is not yet open to the public, at least the interior. Hopefully at some point some good engine room photos of her will surface.
One thing I am often asked by railroad friends when discussing the Cleveland 278A, is “Just what is the difference between an EMD 567, and what parts crossover?” Well, its a simple answer, They are two very different animals, and have zero parts crossover. I figured I would throw this gallery together of doing a full gasket renewal on a 278A, which shows the differences, at least in the cylinder and head area of the engine. Something to keep in mind – the 201A was the father of both this engine, as well as the EMD 567. EMD (EMC) engineers went off and designed the 567 from the mistakes of the 201A with the goals of a railroad engine, and Winton went off and designed the 248 which was the marine service engine, which evolved quickly into the 278/278A as I have mentioned in past articles.
The 278A is best compared to the EMD 567B, in that it uses a water deck style liner. The 278A uses an individual water deck area specific to each cylinder, not one section of the block per say, both of which are sealed with O rings, which cause leaks. Leaks are bad, especially when water gets into the oil side of things. Lets dive into a 278A and go through the process of finding a leak, and how to fix it, and compare the engines along the way. Click on all of the below images for larger versions.
The first sign of trouble, is generally when you see water coming out of the airbox drains. This at least narrows it down to one side, so then you start by pulling all of the covers off, and looking for Niagara Falls.
The leak itself can come from two very different issues – The liner O rings are leaking, as seen in this image. Follow the brown trail of water from the bottom of the airbox, leading up to the liner. A second way of spotting the trouble, is when blowing down the engine, you will get water vapor (or solid streams) coming out of the blow down. This is a second area that leaks, the O rings between the head and the liner. When this happens, water will run down into the liner, and out the intake ports in the liner into the airbox – if the piston is down. This will also cause the expansion tank/water side of the engine to pressurize. More on this shortly. A cracked head can cause this same issue, which can be a bit more troublesome to pin point, especially if it only does it when they are warm.
A third source of water issues on a Cleveland can be in the exhaust elbows. EMD’s have an integral exhaust path, whereas the Cleveland’s have individual exhaust jumpers between the head and the manifold which are all water jacketed. Look closely and you will see pitting in the elbow, causing water to leak into the head and liner through the exhaust valves.
The fourth area of concern, and this is NOT Cleveland specific – is when a liner lets go. In this case, the engine was not blown down before startup, and the liner violently let go (it is a sound I will never forget). The side of the liner pushed out, thus the entire water system dumped out in a hurry into the airbox, once again, Niagara Falls resulted. Now, Cleveland’s have a pressure relief valve on each head, thus when this happened, the valve opened (and shot a solid stream of water out) preventing the connecting rod from bending. EMD’s don’t have this. The only damage from this was the piston rings were broken by the chunk of liner that failed. And on that note – If your running an old engine, take the 5 extra minutes and BLOW IT DOWN every time! It can save you some serious trouble!
Now, we drain the engine down..
…and start to take it apart. Fuel and overspeed lines are removed, rocker assembly removed, exhaust jumper removed. In this case we pulled the injector also, but it is not required.
Sometimes it takes some creativity to get all the tools in there in certain spots on these engines. In this case a chunk pf bent pipe from a handrail was used as a cheater bar. Hey, it worked! 4 nuts hold down the head to the block, and 6 bolts hold the head to the liner. EMD’s the liner sits inside the block, but the Cleveland’s sit on top of the block, and do not use shared crab nuts.
No difference between them here – Lots of rags, and piles of parts!
With the head removed, we see one of the biggest downfalls of the 278A. There is a half moon shaped groove that fits a round rubber seal. When these seals start to go, the engines leak oil, and badly. In the 1950’s, the US Navy devised a tool and a process to push the head back onto this seal before you torque them down. This helps, but not that much. This, is why almost every Cleveland is covered in oil. The valve cover gasket seals (two per cover) are not any better, and are very temperamental. EMD built a box around their oil leaks…
Bottom of the head. Nothing special here. The left is toward the center of the engine. The large hole to the right is where the injector control rods goes into the head.
Now we have the head off. Pulling the head is typically the hardest part of the operation, as the stud holes will fill with oil and sludge, as well as carbon – more on that one shortly. Cleveland’s use direct air start, meaning no starter motor. 300PSI (up to 600 was used on the Sub’s) is directly admitted to the head in order of timing in 8 of the heads – that’s what the small line is just above the right most, lower head stud.
With the head off, we are at a crossroads. If the liner O rings are leaking, you need to forge ahead and pull the liner. If you are getting water through the liner, and the expansion tank is bubbling off – that means you lost a fire ring, which is a solid copper ring that seals between the head and the liner. When this fails, it burns out any number of the 12 small rubber O rings that seal the water side of the head and liner on small copper ferules. We dubbed these the little rubber douchebags. If the liner is still sealing good, you don’t HAVE to pull it, but it is typically good practice to just replace them all while its apart.
To pull the liner, you need a liner lifting plate (we had to make one, we now have an OEM one..). The piston crown has a small tapped hole for an eyebolt, thus you can secure the piston to the plate, and lift them out as one assembly.
But first, you need to pull off the bearing shell from the connecting rod. Cleveland’s use an individual rod and bearing for each cylinder, EMD’s double up with their fork and blade style assembly.
In this one, we pulled the piston out as the rings needed to be changed. 278A’s use a traditional wrist pin assembly, whereas by the later 567A engines, EMD switched to the floating piston.
Pulling the liner out – Cleveland’s have two liners available, a cast style, and a later fabricated style, which are interchangeable. The two ferrules that are closer together are the markers telling you this is the outer edge of the liner.
Liner and piston/rod is out. The rusty area is the where the water enters the liner.
Looking down through the airbox, you can see the water deck area. Water enters through the water manifold that runs through the airbox into the liner. The EMD 567C and Cleveland 498 engine simply used a bolted on extension from the manifold pipe directly to the liner, eliminating these O rings. These O ring seats can actually be changed, but it is an enormous project. You can see here how Cleveland’s have individual connecting rods on each connecting rod journal.
A full gasket kit for a Cleveland, which encompasses all new O rings for numerous things, cork seals for the covers, exhaust jumper gaskets and many other small gaskets.
With the O ring grooves cleaned up, the new O rings are installed and set in a bead of silicone, which helps seal them, as well as keeping them from pulling out when installing the liner back into the block. The liner is lubricated with dish soap to help it slide in.
With the liner back in, a new copper head gasket is installed, new fire ring, and new O rings for the water jumpers and oil seals on the rear of the head. A large cork circular gasket seals the injector control rod hole and the head. EMD’s essentially have all of this combined onto one gasket. Note that the liner is not fully seated down – This will be remedied when the liner is bolted to the head, and it is all cinched down.
With the head back on, everything else goes back together fairly quickly. The head is bolted to the liner with 6 bolts, which are torqued to 175 ft lbs, (290 on the 567B), and the 4 bolts holding the head get torqued down to 650 ft lbs (1800 on the 567B). The exhaust elbow uses two copper clad gaskets, as well as two smaller gaskets for sealing the water side (Cleveland’s are water cooled exhaust). It is a bit tricky to put them on, as the lower bolts are fine thread, and the upper bolts are coarse thread, so you cant mix the bolts up. You essentially have to roll the jumper on, starting with tightening the lower bolts first, in order to compress the gaskets, and line the top up.
Hopefully this answers some more of the mechanical questions of how the 567 and 278 engines compare internally. Down the road I may do something a bit more detailed on this and cover the other portions of the engine, and how they are different, such as the blower, oil and governing systems. Something to note about the Cleveland’s – they require no special tools to take them apart, outside of a torque multiplier.
One of the coolest engines made – the Nordberg Radial. The engine, a 14″x16″ was offered in both 11 and 12 cylinder models, in spark ignition gas, Diesel, and Dual fuel options. I would love to find a manual for one of these!
Happy New Year! We shall begin this year with a brochure – the Winton 201 engine used to power the Century of Progress Exposition in Chicago, held in 1933-4. I was able to get a copy of this a few years back, so here is a scan. Click them all for a larger version.
Eugene Kettering would state in his 567 development paper the following about these engines at the expo:
“The boys worked all night and hoped the engines would run all the next day. It was no fun, but we learned fast and a new design study was soon underway at Winton. To mention the parts with which we had trouble in Chicago would take far too much time. Let if suffice to say that I do not remember any trouble with the dip stick.”
Needless to say, the engines did work at the end of the day, and provided an important stepping stone for Winton and the developments with which would become the 201A engine, to be used in many railcars, locomotives and submarines. While the engine was not entirely a success in the long run, it did lead to the development of the Winton 248 engine for Marine use, and the 567 engine for locomotive use, and the Detroit Diesel 71 line.
Amazingly enough, one of these engines is a survivor, on display at the Illinois Railway Museum in Union, IL. It would become a trade show display for General Motors through the years. Unfortunately, the sister engine to my knowledge disappeared.
I truly hope one day we can see a Winton 201A run again for display.
A few months back, I made a post on the tug Luna and Venus, of the Boston Towboat Company, dubbed Historic Tugs I. The intention was to highlight museum vessels and whatnot with historic documentation and photos. To change that a bit, I am going to start a new series covering just tugs of the 1930’s-1970’s, including both new and repowered boats, using several styles of propulsion. This first tug profiled, will be the M. Moran.
Not much has to be said about Moran Towing, one of the oldest and well known tugboat companies in the world, founded in 1860 by Irish immigrant, Michael Moran. Moran Towing is a well established company, using a vast fleet of tugs, ranging from small 80′ direct reversing Canal tugs, to large, WWII surplus ocean going 165′ tugs, many of which were on charter from the US Navy. Fast forward to 1960: These were all single screw tugs, never exceeding much more then about 2000HP. Moran Towing had a long history of working with TAMS Inc., and later the General Motors Marine Design Section under naval architects Richard Cook and later Joe Hack.
In the era, just about every tug was considered “Ocean Going” (a scary thought..), however in reality only the larger, WWII era tugs really were just that, with the rest being glorified harbor and coastal tugs. Joe Hack would design Moran a 120′ tug, with a 31′ beam, and an 18’9″ depth. A new first for Moran was also introduced – twin screw propulsion.
The tug was named the M. Moran, after the founder of Moran Towing’s Michael Moran. She would be the 7th tug named for him. The M. Moran was designed for an 11,000 mile range, or anywhere in the world – holding a capacity of 75,000 gallons of fuel. The M. Moran was built in Texas, by Gulfport Shipbuilding.
The M. Moran had a rather unorthodox layout, using two split levels underneath the wheelhouse, giving her a rather odd, low profile appearance, but affording a massive amount of interior space. 9 full staterooms, two of which were dubbed a radio room, and a sick bay. A large central galley was located over the engine room – thus she lacked any actual upper engine room, also known as a fiddley. Behind the galley was a space for a 75HP Almon-Johnson towing machine.
You guessed it – the M. Moran was Diesel-Electric, powered by a pair of Cleveland Diesel, 1750HP 16-278A engines, with Allis-Chalmers main generators – all WWII surplus equipment, giving her a rating of 3,500HP. The engines were factory rebuilt, and were originally installed in US Navy Landing Ship LSM-529 (engine #55810), and LSM-324 (engine #55284). Ironically the other engine from LSM-324 would also go to Moran, re-powering the steam tug Michael Moran. The tug had a pair of Detroit Diesel 6-71’s for generators, as well as a piggyback shaft generator belt driven on top of each main generator. The tug had a pair of 9′ 10″ wheels, and a rated bollard pull of 95,000lbs.
The wheelhouse of the M. Moran featured American Engineering electric-hydraulic steering system, and the same Lakeshore throttle stands used by Cleveland for a number of years, of course modified for twin screw. A Sperry gyro, and radar rounded out the interior – pretty spartan, even for its time. While the maneuverability of Diesel-Electric is well known, an interesting feature of the M. Moran – being twin screw, was the cross-compatibility. The tug could run on only one engine, and power both propulsion motors when running around lite tug, somewhat of a throwback to the Destroyer-Escorts of WWII (where the propulsion motors in the tug originated), where various combinations of engines could power certain groups of motors.
The M. Moran was placed in service on 9/27/1961, and her very first trip, just a week later – would take her all the way to Pusan, South Korea, towing the 30,000kW generating barge Resistance, a WWII LST converted into a powerplant. The M. Moran was well covered in Cleveland Diesel’s Diesel Times newsletter Diesel Times, as well as several issues of Moran Towing’s own newsletter, Tow Line.
By the late 1960’s the M. Moran would gain a large upper wheelhouse. She would spend many years running around the Gulf area towing large project cargo, as well as the occasional foreign tow. The M. Moran was briefly renamed as the Port Arthur for a brief time in the early 1970’s, likely operating under a charter.
Moran would go on to order a 2nd tug, to the same design as the M. Moran, named the Esther Moran. The Esther would be built in New York, by Jakobson Shipbuilding. At the same time, Jakobson also built the Patricia and Kerry Moran, which used the same hull design, however it was shortened 12′ with the tug being setup for harbor work, thus lacking the towing machine and split levels. These three tugs would be the last new tugs powered by Cleveland 278A engines. Cleveland was rolled into Electro-Motive in late 1961.
Both the M. Moran and the Esther were not Cleveland powered very long. Both tugs would be repowered with EMD 16-645E engines with air clutches by the end of the 1960’s, giving them a new rating of 6,300HP – a massive amount of power at the time. Joe Hack would revisit the split level design with a pair of tugs for Gulfcoast Transit, the Katherine Clewis and Sarah Hays.
In 2000, Moran sold both the M. Moran and Esther Moran to Canada’s McKeil Marine. The M. Moran became the Salvager, and the Esther as the Salvor. The Salvager became the Wilfred Seymour in 2004, later being shortened to Wilf Seymour. Both tugs operate in the Great Lakes, and both would be converted into Articulated Tug-Barge combinations, with the Wilf getting a Bludworth coupler, and the Salvor a JAK system. The Salvor was laid up in 2018, and the Wilf is still in service.
Noted maritime artist Carl G. Evers would do several paintings of the M. Moran, including one of her in Korea. Several of Carl’s paintings have graced the cover of Moran’s Tow Line.
Engine #7 at Delta is a 10 cylinder, 3500HP, Dual Fuel engine. The engine is rated for only 277 RPM, and has an 18″ bore and a 27″ stroke.
Click on all of the photos for a larger version.
The creative use of old stop signs are covering the exhaust ports, which would turn and enter into the flood in the circular covers.
One of the fuel injection pumps. A camshaft in the box underneath drives these, with a copper line out of the top leading to the fuel injection nozzle in the head.
The engine drive a Fairbanks-Morse 2130kW, 2400V AC Alternator. The excitation generator is belt driven off off the end.
Looking down at the top of the cylinder head. The large pipe leading into the top of the head is the incoming Natural Gas supply. Going clockwise, is the gas admission valve driven from the upper camshaft, the air start check valve, with the air supply under it, jacket water exit into the upper water header, above that is the cylinder relief valve. In the center is the fuel injection nozzle. According to the builders plate, this engine is a 31A18 – FM documentation calls the Dual Fuel engine a 31AD18, maybe this engine was converted after installation?
The pipes in the foreground are the previously mentioned exhaust pipes, which were removed for remediation.
Just outside of the engine hall, is a small clean air room. Inside, is the scavenging air blower for the engine (all 10 cylinder engines used an external blower) – a Roots-Connersville 24″ centrifugal blower. The blower, is rated at a whopping 300HP and moves 17,500CFM of air.
Just how big is an 18″ piston? Here it is with a dollar bill for reference..
Gauge and alarm panel – Just not as cool as those 1930’s era ones on the 32E engines..
The photos here simply do not do this engine justice, and just how BIG it is!
Lubrication chart for the engine. I would LOVE to add one of these to my collection. Anyone got one they want to sell?
This concludes our tour of the Delta Municipal Light & Power Plant. Thanks again to the guys for the fantastic tour! I can only hope that this plant can be saved, or at least some of the engines. I would love to see the 31A18 saved, but realize that would be one hell of a feat, due to the shear size. That little 4 cylinder 33 would be a neat museum piece as well.. I may make another post down the road with some other random photos in the plant I took.
Next week starts a new series – Historic Boat Profiles, with our first featured boat being the tug M. Moran, Moran Towing’s first twin screw tug.
Moving down the line of engines we get to engines #3, 4 and 5, all of which are Fairbanks-Morse 32E14 engines. The 32E was a descendent of the model Y engine, first introduced in 1923, and subsequently went through several upgrades over the years. The engine, offered in two sizes: A 12″x15″ and a 14″x17″. The engines were identical, other then the bore and stroke, with the 12″ offered in 1, 2 and 3 cylinder models, and the larger 14″ in 1, 2, 3, 4, 5 and 6 cylinder options. The 32E engine is a 2 stroke Diesel, and used a unique backflow scavenging, in which on the up stroke of the piston, air is pulled into the crankcase through a simple air valve on the crankcase door, is compressed on the downstroke, and when the piston uncovers the exhaust and intake ports on the liner, the compressed air forces the exhaust out, a very simple and effective method, requiring no camshaft operated valves in the cylinder head. An oil pump kept a force feed lubricator full, which handled the oiling on the cylinder walls, wrist pins and crank pins, as well as keeping a certain oil level maintained at each of the main bearings using a series of drilled passageways. The engine had no water pump of its own, relying on an external pump in the plant. A plunger type fuel pump was operated by a camshaft on the governor drive. The engines originally used a very basic FM flyweight style governor, and later used a Woodward IC unit. The 32 line would become one of the most popular engines of its time, powering numerous rural communities and small business (be it power generation or through a line shaft).
Click on all photos below for a larger version.
Engine #4 is a 300HP engine at only 300RPM, driving a 148kW alternator.
The 32E engine commonly used a very basic exhaust system, where each cylinder simple exhaust into a downward pipe, that tie into a chamber under the floor that runs outside to the muffler.
Engines #4 and 5 are smaller 3 cylinder, 225HP engines. Unfortunately, I did not get the size of the alternators that they drive.
The pipe above the exhaust manifolds is the upper water header. These are extremely basic engines, and while today are tiny in terms of ratings, several are still in service all around the country, not only in their original plants, but many preserved at old engine clubs.
Behind each alternator, the same shaft also turns the excitation generator.
Next week will be the final part of the Delta series, covering the biggest engine in the plant, the 31A18. After that we will start a new series, Historic Boat Profiles, as well as returning to vintage advertising and some great articles which have been in the works for several months behind the scenes.
The Delta plant is home to a trio of F-M model 33 engines. Before we get to those, here is a little background on the Model 33 engine.
The Model 33 engine was the next model in line after the 32 series, and was introduced around 1930. The engine was ultimately offered in 3 bore sizes – a 12″, 14″ and 16″. The engine was FM’s first pump scavenged engine, moving up from the older crankcase scavenged 32. Like the predecessor, these were rather simple engines. No intake or exhaust valves, mechanical fuel injection (in a time when air injection was still somewhat common) and a split lubrication system using both an engine driven pressure pump and a force feed mechanical lubricator.
In the case of this post, we will be describing the 16″ bore model, which has a 20″ stroke rated at 300RPM. FM offered these engines in 4, 5, 6, 7, 8 and 10 cylinder sizes. The engine was available with a dual fuel option, meaning it could run on Diesel, or Natural Gas with Diesel acting as a pilot fuel. A second upper camshaft drives a series of gas valves at each cylinder head. The Delta plant has 3 of these engines: