General Electric had developed the 7FDL16 engine for use in diesel-electric railroad locomotives. Its design and rating are based on extensive laboratory tests backed up by thousands of hours of field experience.

 16-cylinder four-stroke cycle, turbocharged diesel engine with 9-inch by10-1/2 inch cylinders in a 45 degree Vee arrangement. The engine has an integral head and cylinder arrangement which can be removed in a minimum of time. It is equipped with cast-iron pistons, valve seat inserts and the Bendix fuel system. The cylinder liner is chrome plated and 3/16 inches thick.

General specifications of the engine are: 

GOVERNOR

The engine governor is of the self-contained, electro-hydraulic type. It automatically regulates the horsepower output at each throttle setting.

OVERSPEED PROTECTION

The engine is automatically shut down if the speed exceeds maximum rated rpm by 10 percent.

COOLING SYSTEMS

Water is circulated through the engine, turbo-supercharger, radiator, and lubricating - oil cooler by a gear-driven centrifugal pump integral with the diesel engine. An expansion tank is provided with a sight gage to indicate water level; fill pipes are located on each side and at the roof of the locomotive.

ENGINE TEMPERATURE CONTROL

A flow control valve, thermostatically operated, automatically maintains temperature by regulating the flow of cooling water through the radiator sections.

FUEL SYSTEM

A motor-driven pump transfers fuel from the tank through filters to the injection pumps.

Each cylinder is equipped with a high-pressure fuel injection pump and injector.

LUBRICATING SYSTEM

A full-pressure system is supplied by a gear-type pump integral with the diesel engine.

A lubricating-oil reservoir is located in the engine subbase. Lubricating oil filters, strainer, and water-cooled oil cooler are provided. Abnormally low lubricating oil pressure automatically shuts down the engine.

ENGINE STARTING

The diesel engine is cranked by the traction generator from storage battery power.

The following terms are used throughout this paper in locating various components of the engine. (See FIG 1 through 3)Their designation or explanation is as follows:

FREE END - The end of the engine where the turbocharger and inter-coolers are mounted.

GENERATOR END - The end of the engine where the generator is mounted.

RIGHT AND LEFT SIDE - The right or left side of the engine is determined by viewing the engine while facing the generator end.

CYLINDER LOCATION - The cylinders are numbered from the FREE END to the GENERATOR END. (Number 1 Right and 1 Left cylinders are nearest the turbocharger. Number 8 Right and 8 Left cylinders are nearest the generator.)

CRANKSHAFT ROTATION-During engine operation the crankshaft rotates clockwise when viewed from the FREE END or counterclockwise when viewed from the GENERATOR END.

FIG 1

FIG 2 - GE Engine Front End

FIG 3 - GE Engine Generator End

MAIN FRAME

The engine mainframe is a single-piece casting of special ductile castiron reinforced by ribs and gussets. Further strength and rigidity are added to the frame by bolting the main bearing caps horizontally as well as vertically. Four machined surfaces are used for mounting the mainframe on the locomotive platform. Corrosion problems created by coolants are common in other types of engines are completely eliminated. The cooling water does not contact any part of the frame. The crankcase inspection covers are lightweight with a quick-acting single handle release.

CRANKSHAFT

The crankshaft is forged of high-quality steel and nitride hardened for long life. The journal surfaces are precision ground and all bearings surfaces are force-fed with lubricating oil. A removable, split drive gear, mounted on the generator end of the shaft, drives the camshafts, and through gears, the control and over speed governor.

The traction generator armature is directly bolted to the crankshaft flange

BEARINGS

Replaceable, precision-fit main and connecting rod bearings are used.

They have steel back sand are lined with a copper-lead alloy. The crankshaft thrust bearings are located in the No. 8 main bearing. The camshafts rotate in replaceable, split-sleeve type, aluminum bearings.

VIBRATION DAMPERS

One round, sealed, viscous type, the damper is mounted on the free end of the crankshaft. This unit dampens and controls crankshaft torsional vibration.

CAMSHAFT

Two camshafts of forged high alloy steel are used to operate the engine valves and fuel pumps. These shafts are mounted in the frame on each side of the engine and are directly gear driven from the crankshaft at one-half crankshafts peed. The fuel and valve cams on these shafts are individually replaceable.

CONNECTING ROD ASSEMBLY

Each connecting rod assembly consists of a master connecting rod and an articulated connecting rod. These rods are made of forged alloy steel. The articulated-rod bolts to a pin fitted in the master connecting rod and the master connecting rod are bolted to the crankshaft. This design provides for a maximum of bearing surface area.

PISTONS

The pistons are of a special castiron giving them the ductility needed for long piston life. Each piston is equipped with four compression rings and two oil rings. The piston rings may be inspected and replaced without disconnecting the piston by removing the cylinder. The lower piston area is tin-plated to aid rapid piston break-in and to prevent scuffing which would cause cylinder damage. The pistons are lubricated and cooled by oil. Oil is forced through holes drilled in the connecting and articulated rods to the piston pins and the cavity under the piston crown.

CYLINDERS

Cylinder castings are of a special ductile castiron with the cylinder head an integral part of the casting. Hardened replaceable intake and exhaust valve seats are installed in the cylinder head. The valves are arranged with the two intakes.

valves outboard and the exhaust valves toward the center of the engine vee. This design allows for unidirectional gas flow and provides the optimum engine breathing which results in lower exhaust temperature and longer engine life. The fuel pump injection nozzle, valve rocker arms, and allied valve equipment are located within the upper portion of the cylinder casting. The cylinder casting is bolted to the mainframe. The bolt-in glugs are located at the bottom of the cylinder to keep hold-down stresses away from the maximum pressure area in the cylinder head.

CYLINDER LINERS

Replaceable, water-cooled, centrifugal castiron cylinder liners are provided. The liner wear surfaces are chrome plated to give longer liner life. The upper end of the liner is seated on a soft, embedded, copper gasket. The lower end is sealed with a rubber O-ring, held in place by a packing ring. The liners are installed in the cylinders with an interference fit and secured in place with a bolted clamping ring.

FUEL INJECTION PUMP

An impulse or jerk-type fuel injection pump is mounted on the top of each cylinder head and operates through a pushrod from the camshaft. Ana adjustable tappet located below the pump pushrod provides adjustment for pump timing. The pump increases fuel pressure for injection, accurately measures the quantity to be injected, and delivers the fuel at the proper time to the fuel nozzle. The pumps are controlled by the governor to measure and deliver the fuel at the proper time and in the amount required for a given horsepower load.

FUEL NOZZLES

An injection nozzle is mounted in the center of each cylinder and is connected to the fuel injection pump by a short high-pressure line.

Fuel is forced through tiny holes in the nozzle tip which atomize the fuel into a very fine mist in a symmetrical pattern for proper combustion. The injection nozzles are made up of several easily replaceable components.

ENGINE CONTROL GOVERNOR

The engine is equipped with an electro-hydraulic, speed regulating governor which is equipped with a small, internally-mounted load controlling rheostat. The governor is mounted on top of the engine mainframe at the generator end and is gear driven from the right camshaft gear. The governor maintains desired engine speeds at all loads by regulating fuel rack travel to the fuel pumps.   The governor has its own oil supply and its own oil pump which supplies the pressure needed to regulate the operation of the governor.

TURBOCHARGER

A single turbocharger, mounted on top of the mainframe at the free end is driven by the engine exhaust gases and provides air at approximately twice atmospheric pressure to the cylinders. The turbocharger is water-cooled and lubricated with oil from the pressurized system of the engine.

INTERCOOLERS

The engine is equipped with two intercoolers, which are small enclosed radiators mounted on each side of the engine. They are connected between the turbocharger and each air intake manifold. Part of the cooling system water flows through the intercoolers and compressed air from the turbocharger blows across the radiator cores. The water absorbs heat from the air which allows cooler air to be delivered to the cylinders. Supplying cooler air for combustion enables a greater amount of fuel to be burned with a given amount of air which greatly increases engine power.

MANIFOLDS

The air intake manifolds are mounted to the outside of each bank of cylinders. They are sectional in construction for ease in alignment and quick engine maintenance. The exhaust manifolds, mounted in the VEE of the engine, are stainless steel with gasketed flange connection to each cylinder and the turbocharger. The individual exhaust pipes have bellows sections at appropriate intervals to compensate for thermal expansion with varying engine loads.

AIR SYSTEM

Incoming engine air first passes through the locomotive primary air cleaner. This cleaner contains a multitude of specially constructed tubes that act as miniature cyclonic dirt separators. Better than 95 percent of the air-borne dirt is removed by the cleaner and is discharged beneath the locomotive. This cleaned air passes through panel-type oil bath air filters for additional filtration before it enters the turbocharger.

FIG 5 - GE Engine Fuel Injection System

COOLING SYSTEM

Cooling water is circulated through the system by an engine-mounted water pump. The pump is mounted on the free end cover and is gear driven from the crankshaft. Cooling water is forced through the engine, turbocharger, oil cooler and intercoolers to carry engine heat away. Hot water flow is controlled by a flow control valve that directs water to the roof-mounted radiators where the water is cooled by forced air from the gear-driven radiator fan.

FUEL SYSTEM

Fuel is pumped through the system by an externally mounted, electric-motor driven fuel booster pump. The pump transfers fuel from the locomotive fuel tank through filters to each fuel injection pump. Excess fuel returns to the tank through sight glass and regulating valve. A relief valve is installed near the pump to protect the system against excessive pressure.

LUBRICATION SYSTEM

Lubricating oil is circulated through the engine by the gear-driven lube pump mounted on the free end cover. The entire engine is automatically lubricated with oil pressure controlled by a regulating valve. A relief valve is installed to protect the system against excessive pressure. An externally mounted, water-cooled, oil cooler, cools the oil which picks up heat in lubricating and cooling the pistons and allied parts.

LUBRICATING OIL FILTERS

A full-flow strainer and externally mounted filters are installed in the lubricating oil system to filter out abrasives or foreign matter.

SAFETY DEVICES

The engine is equipped with an Overspeed governor which shuts the engine down if the engine speed exceeds a predetermined safe value. The governor is mounted on the governor drive gearbox which is located at the generator end and is gear driven from the camshaft gear. When the governor trips, it closes butterfly valves located in the air-intake manifolds, which shut off air to the engine. A manual reset button is provided to reset the governor after an Overspeed trip. This Overspeed governor is fail-safe. Any failure of the Overspeed mechanism itself will automatically shut the engine down.

A safety device to detect low engine lube oil pressure is built-in to the speed-regulating governor and is connected to the engine lube oil header. It provides low lube oil pressure protection throughout the entire engine speed range. Should the lube oil pressure drop below a safe value the device shuts down the engine. A manual reset button is provided to reset the pressure device after a low oil pressure shutdown. A YELLOW indicating lamp is provided to inform the operator when an engine shut-down is caused by low oil pressure.

An alarm bell and a RED indicating light are provided to inform the operator if the engine water temperature exceeds a safe value.

CRANKING

The engine crankshaft is directly connected to the traction generator armature. When the generator is electrically energized (from batteries) through its start field, the generator acts as a motor to rotate the crankshaft to start the engine.

Cooling water is circulated through the system by an engine-mounted water pump. The pump is mounted on the free end cover and is gear driven from the crankshaft. Cooling water is forced through the engine, turbocharger, oil cooler and intercoolers to carry engine heat away. Hot water flow is controlled by a flow control valve that directs water to the roof-mounted radiators where the water is cooled by forced air from the gear-driven radiator fan.

FIG 6 - GE Engine Cooling Water System