EMD 710

The EMD 710 is a line of diesel engines built by Electro-Motive Diesel (previously General Motors' Electro-Motive Division). The 710 series replaced the earlier EMD 645 series when the 645F series proved to be unreliable in the early 1980s 50-series locomotives which featured a maximum engine speed of 950 rpm.[1] The EMD 710 is a relatively large medium speed two-stroke diesel engine that has 710 cubic inches (11.6 liters) displacement per cylinder,[2] and a maximum engine speed of 900 rpm.[note 1]

EMD 710
An EMD 12-710G3B engine, installed in an Iarnród Éireann 201 class locomotive
Overview
Manufacturer	Electro-Motive Diesel
Also called	G-Engine
Production	1984-present
Layout
Configuration	V8, V12, V16, and V20
Displacement	710 cubic inches (11,600 cm^3) per cylinder
Cylinder bore	9 ^1⁄16 in (230 mm)
Piston stroke	11 in (280 mm)
Block material	Flat, formed and rolled structural steel members, and steel forgings, integrated into a weldment
Head material	Cast iron, one per cylinder
Valvetrain	4 Valves per cylinder, SOHC
Compression ratio	15.3:1
RPM range
Idle	200
Redline	904 (950 on G3C models)
Combustion
Supercharger	Centrifugal
Turbocharger	Hybrid turbocharger, below half throttle, clutch-driven blower takes over
Management	Electronic
Fuel type	Diesel
Oil system	Wet sump
Cooling system	Liquid cooling
Output
Power output	203 kilowatts (272 hp) per cylinder
Dimensions
Dry weight	up to 25.57 tonnes (25.17 long tons; 28.19 short tons)
Chronology
Predecessor	EMD 645
Successor	EMD 1010 - the heavily redesigned and refined EMD 265H to meet Tier-4 emission standard

In 1951, E. W. Kettering wrote a paper for the ASME entitled, History and Development of the 567 Series General Motors Locomotive Engine,[3] which goes into great detail about the technical obstacles that were encountered during the development of the 567 engine. These same considerations apply to the 645 and 710, as these engines were a logical extension of the 567C, by applying a cylinder bore increase (645), and a stroke increase (710), to achieve a greater power output, without changing the external size of the engines, or their weight, thereby achieving significant improvements in horsepower per unit volume and horsepower per unit weight.

Since its introduction, EMD has continually upgraded the 710G diesel engine. Power output has increased from 3,800 horsepower (2,800 kW) on 1984's 16-710G3A to 4,500 horsepower (3,400 kW) (as of 2012) on the 16-710G3C-T2, although most current examples are 4,300 horsepower (3,200 kW).

The 710 has proved to be exceptionally reliable, but the earlier 645 is still supported and most 645 service parts are still in new production, as many 645E-powered GP40-2 and SD40-2 locomotives are still operating after four decades of trouble-free service, and these often serve as a benchmark for engine reliability, which the 710 would meet and eventually exceed, and quite a number of non-SD40-2 locomotives (SD40, SD45, SD40T-2, and SD45T-2, for example, and even some SD50s), have been rebuilt to the equivalent of SD40-2s with new or remanufactured engines and other subsystems, using salvaged locomotives as a starting point. Some of these rebuilds have been made using new 12-cylinder 710 engines in place of the original 16-cylinder 645 engines, retaining the nominal rating of 3000 horsepower, but with lower fuel consumption.

Over the production span of certain locomotive models, upgraded engine models have been fitted when these became available. For example, an early 1994-built SD70MAC had a 16-710G3B, whereas a later 2003-built SD70MAC would have a 16-710G3C-T1.

The engine is made in V8, V12, V16, and V20 configurations, although most current locomotive production is the V16 engine, whereas most current marine and stationary engine production is the V20 engine.

Specification

All 710 engines are two-stroke 45 degree V-engines. The 710, and the earlier 645 and 567, are the only two-stroke engines commonly used today in locomotives. The 710 model was introduced in 1985 and has a 1-inch (25 mm) longer stroke (now 11 in or 279 mm) than the 645 (10 in or 254 mm stroke). The engine is a uniflow design with four poppet-type exhaust valves in the cylinder head. For maintenance, a power assembly, consisting of a cylinder head, cylinder liner, piston, piston carrier, and piston rod can be individually and relatively easily and quickly replaced. The block is made from flat, formed, and rolled structural steel members and steel forgings welded into a single structure (a "weldment"). Blocks may, therefore, be easily repaired, if required, using conventional shop tools. Each bank of cylinders has a camshaft which operates the exhaust valves and the Unit injectors.[4]

Pre-1995 engines have mechanically controlled unit injectors (UIs), patented in 1934 by General Motors, EMD's former owner. Post-1995 engines have electronically controlled unit injectors (EUIs) which fit within the same space as a unit injector.[5] An EUI is EMD's implementation of non-common-rail electronic fuel injection on its large-displacement diesel engines.

See EMD 645 for general specifications common to all 567, 645, and 710 engines.

Unlike the two earlier engines, which could use either a Roots blower or a turbocharger, the 710 engine is (normally) offered only with turbocharging. The turbocharger is a consists of a gear train driving over-running clutch to drive an impeller, allowing the turbocharger to act as a centrifugal blower at low engine speeds (when exhaust gas flow and temperature alone are insufficient to drive the turbine) and a purely exhaust-driven turbocharger at higher speeds. The turbo-compressor can revert to compressor mode momentarily during demands for large increases in engine output power. While more expensive to maintain than Roots blowers, EMD claim significantly reduced fuel consumption and emissions, improved high-altitude performance, and even up to a 50 percent increase in maximum rated horsepower over Roots-blown engines for the same engine displacement. But, unlike the earlier 645 and 567, which could use either turbochargers or Roots blowers, EMD's clutched turbocharger is an integral part of most 710 models.

Horsepower for any naturally aspirated engine is usually derated 2.5 percent per 1,000 feet (300 m) above mean sea level, a tremendous penalty at the 10,000 feet (3,000 m) or greater elevations which several Western U.S. and Canada railroads operate, producing as much as a 25 percent power loss. Forced induction effectively eliminates this derating.

Certain engines have been delivered with modifications that permit lower fuel consumption (but possibly at the expense of higher emissions or reduced power output), lower emissions, or even higher power (such as by replacing the clutched turbocharger with a conventional turbocharger feeding a Roots blower, but this increases fuel consumption).

Rail versions

ID	Engine type	Max RPM	Power (hp)	Power (MW)	Introduced	Locomotive(s)
8-710G3A-T2	V8	900	2150	1.6	2007	GT38ACe, GT38LC, Romanian Class 63, Class 65, Class 66-2, EGM-621
8-710G3A-T3	V8	900	2150	1.6	2007	SD20ECO, GP20ECO, SD22ECO, GP22ECO
8-710G3B-T2	V8	900	2200	1.6	NA	EMD JT38CW-DC
12-710G3A	V12	900	3000	2.2	1985	GP59, F59PH, Australian National DL class, New South Wales 82 Class.
12-710G3B-T2	V12	900	3150	2.3	2007	SD32ECO EFI equipped.
12-710G3C-U2	V12	950	3150	2.3	2006	Euro 3000 EFI equipped.
12-710G3C-EC	V12	950	3200	2.3	1993	F59PHI EFI equipped.
12N-710G3B-EC	V12	900	3200	2.5	1998	British Rail Class 66, British Rail Class 67, British Rail Class 69, Irish Rail 201 Class, RENFE Class 334, EMD DE/DM30AC
12N-710G3B-ES	V12	900	3200	2.5	1998	WAGR S class (diesel), Downer EDI Rail GT42CU AC, Downer EDI Rail JT42C-DC.
16-710G3A	V16	900	3800	2.8	1984	GP60, GP60M, GP60B, SD60, SD60M, SD60I, SD60F, Australian National AN Class, New South Wales 90 Class.
16-710G3B	V16	900	4000	3.0	1992	Early SD70, SD70M, SD70MAC and SD70I.
16-710G3B-EC	V16	900	4000	3.0	1997	SD70, SD70M, SD70MAC and SD70I models equipped with electronic fuel injection (EFI)|EMD GT46MAC EMD GT46PAC (Indian Rail Class WDG-4 and WDP-4)
16-710G3B-ES	V16	900	4000	3.1	1997	Downer EDI Rail GT46C
16-710G3B-T1	V16	900	4000-4200	3.0-3.1	2003	EPA Tier 1 Emissions compliant/EFI Equipped SD70M, SD70MAC, Alstom PL42AC EPA Tier I emissions compliant/EFI equipped.
16-710G3B-T2	V16	900	4000	3.0	2005	SD70M-2 (Norfolk Southern), MP40PH-3C EPA Tier II emissions compliant/EFI equipped.
16-710G3C	V16	950	4300	3.2	1995	SD75M, SD75I.
16-710G3C-EC	V16	950	4300	3.2	1995	SD75M, SD75I, SD90/43MAC EFI equipped.
16-710G3C-ES	V16	950	4300	3.2	2007	Downer EDI Rail GT46C ACe
16-710G3C-T1	V16	950	4300	3.2	2003	SD70M (late model), SD70MAC (late model)
16-710G3C-T2	V16	950	4300-4500	3.2	2004	SD70ACe, SD70M-2, SD70ACS, SD70ACe/45, EPA Tier II emissions compliant/EFI equipped.
16-710G3C-U2	V16	950	4300	3.2	2006	Euro 4000 EFI equipped.
20-710G3B-ES	V20	900	5000	3.7	1995	SD80MAC EFI equipped, GT50AC (Indian Railways WDG5)
20-710G3C-ES	V20	950	5300	3.9	2011	SD80ACe EPA Tier 1 Emissions compliant.

Stationary/Marine versions

EMD E23G[6]
Overview
Manufacturer	Progress Rail
Layout
Configuration	V8, V12, V16, and V20
Displacement	710 cubic inches (11,600 cm^3) per cylinder
Cylinder bore	9 ^1⁄16 in (230 mm)
Piston stroke	11 in (280 mm)
Block material	Flat, formed and rolled structural steel members, and steel forgings, integrated into a weldment
Head material	Cast iron, one per cylinder
Valvetrain	4 Valves per cylinder
Compression ratio	16:1
RPM range
Idle	315
Redline	904
Combustion
Supercharger	Centrifugal
Turbocharger	Hybrid turbocharger, below half throttle, clutch-driven blower takes over
Management	Electronic
Fuel type	Natural gas
Oil system	Wet sump
Cooling system	Liquid cooling
Output
Power output	193 kilowatts (259 hp) per cylinder
Dimensions
Dry weight	up to 25.85 tonnes (25.44 long tons; 28.49 short tons)
Chronology
Predecessor	none, this variant is a conversion
Successor	Caterpillar CG170

Like most EMD engines, the 710 is also sold for stationary and marine applications.

Stationary and marine installations are available with either a left or right-hand rotating engine.

Marine engines differ from railroad and stationary engines mainly in the shape and depth of the engine's oil sump, which has been altered to accommodate the rolling and pitching motions encountered in marine applications.

Engine Speed

• Full . . . . . . . . . . . . . . 900 RPM
• Idle . . . . . . . . . . . . . . 350 RPM

Compression Ratio . . 16:1

Brake Horsepower (ABS Rating)

• Model 710G7 Engines
  • 8-cylinder: 1800
  • 12-cylinder: 2800
  • 16-cylinder: 3600
  • 20-cylinder: 4300

See also

• EMD 567
• EMD 645
• EMD 1010

References

Notes

1. Same parts suitable for 1000 rpm speed, yet rated lower because of earlier problems in EMD 645. Factory-fitted governor limits to 900 rpm.

Specific

1. 40-series versions of the 645, save the initial teething problems with the 20-645E, which were eventually resolved, proved to be exceptionally reliable.
2. "Progress Rail" (PDF). www.emdiesels.com.
3. Kettering, E.W. (29 November 1951). History and Development of the 567 Series General Motors Locomotive Engine. ASME 1951 Annual Meeting. Atlantic City, New Jersey: Electro-Motive Division, General Motors Corporation.
4. Bernard Challen, Rodica Baranescu (ed.), Diesel Engine Reference Book Second Edition, Butterworth-Heinemann 1999 ISBN 0 7506 2176 1 pg 598
5. The camshaft still operates the unit injector's built-in plunger pump, but the electronics control the timing of certain events within the unit injector, as directed by the engine control system.
6. "Progress Rail-Natural Gas Solutions".

General

• Houk, Randy (14 December 2012). "The History of EMD Diesel Engines". Pacific Southwest Railway Museum. Archived from the original on 22 July 2014. Retrieved 5 January 2015.
• John's Alaska Railroad Page. Locomotive roster. Retrieved on September 8, 2006.
• Electro-Motive Diesel. SD70ACe. Retrieved on September 8, 2006
• Electro-Motive Diesel. SD70MAC. Retrieved on April 19, 2004 (courtesy Internet Archive Wayback Machine).
• EMD SD80MAC Operators Manual - GM-EMD 1996
• EMD SD70MAC Operators Manual - GM-EMD 1998

External links

• List of engines under Tier 0, I, and II standards
• SD70 engines (See bottom.)
• Houk, Randy (14 December 2012). "The History of EMD Diesel Engines". Pacific Southwest Railway Museum. Archived from the original on 22 July 2014. Retrieved 5 January 2015.
• EMD 710 engine A 16-710G is shown; turbocharged 567 and 645 engines appear similarly. Whether 710, 645 or 567, these engines have the same external dimensions, with the possible exception of accessories.