Nagumo F-series engine

Nagumo F-series
Overview
Manufacturer	Nagumo Heavy Industries
Also called	FSL, FSLD, FSLH
Production	1991 - Present
Layout
Configuration	Straight-six diesel engine
Displacement	10.5 litres (640.7 cu in)
Cylinder block material	Cast iron
Cylinder head material	Cast iron
Valvetrain	OHV
Combustion
Turbocharger	Waste gate
Management	mechanical
Fuel type	Diesel, Hydrogen Fuel Cell, Multifuel
Oil system	Wet sump
Cooling system	Water-cooled
Output
Power output	Application dependent

The Nagumo F-series engine is a straight-six diesel engine designed and produced by Nagumo Heavy Industries Powertrain Division. It displaces 10.5litres and began production in 1991 as the NSL and NSLD (defense) at Nagumo Powertrain Plant 5 in Fushou.

The F-series engine is a road going version of the larger Nagumo E-series engine, which is typically utilized for heavy industrial use in generators, mining equipment and other heavy duty functions. The F-series is widely utilized in Jin Yi for heavy and medium duty applications such as buses, trucks, and other vehicles. The F-series production D is used specifically for defense applications and continually developed.

The F-series engines are available with multiple emissions packages to fulfill emissions requirements in various nation but the most common is the Schedule C emissions control package, which is required for certain areas of Jin Yi.

In 2014, Nagumo announced the release of the FSLH engine powered by a hydrogen fuel cell on the same F-series architecture and currently offers four different power tunes for these engines.

Models

FSL

Model	Engine code	Displacement	Fuel	Output
FSL	FSL-PA	10.5	Diesel	250 hp, 850 lb/ft
	FSL-PB			260 hp, 1010 lb/ft
	FSL-PC			350 hp, 1510 lb/ft
	FSL-PD			500 hp, 1820 lb/ft
	FSL-PE			750 hp, 2200 lb/ft

FSLD

The FSLD is a production variant for the defense industry released in 1992 for the ZZPT92155 "Haru" self-propelled gun. This early variant produced 650 horsepower and 1,050 pound force-feet of torque. Per Jin military specifications, it was a multifuel engine capable of burning diesel, gasoline, kerosene, and other types of common fuels. While the engine runs best on diesel, it has the ability to adjust injection timing and uses multifuel injectors to allow the engine to run on other fuels should it be necessary. Rather than diesel lubrication of the fuel pump and other key components, these components are lubricated oil, allowing the engine to run thinner fuels if necessary without issue. This also allows poor quality fuel to be mixed in and permits the engine to run on mixtures of different fuels if a unit is running low on supplies in the field. The engine comes with a grid heater on the intake standard, which heats the air coming into the intake during ignition to aid cold weather starts and is a standard feature on all Nagumo engines.

Later variants of the FSLD are equipped with additional fuel-management and engine-management software designed to be installed aboard a vehicle on a separate computer. This computer acts as a complete interface with the engine, allowing the crew to diagnose issues and read engines codes in the moment. The fuel-management software is a more advanced version of what is already programmed into the ECU, allowing for more advanced regulation of the injectors, timing, and fuel pumps in order to better regulate fuel consumption at different engine loads. An optional damage-management package also integrates additional sensors into the engine, allowing advanced readouts of damage and offering damage control options.

There are multiple power ranges and multiple packages available. A cold weather package adds a 1500w block heater and a 650w fuel tank heater, in addition to a heated fuel/water separator in order to aid the engine in starting in subzero winter temperatures. Additional insulation around the fuel lines, injectors, and fuel filters assist in heat retention. For engines that have an auxiliary power unit that can run separate from the engine, all of the cold weather heating functions can be run independently of the engine, keeping the engine warm for rapid starts. All cold weather package engines can also be ordered without provisions for climate control, such as no air conditioning compressor, since those would both need to be electric in order to function with the engine turned off.

For high idle applications, a heavy duty package is available which includes a dry sump oil system. While this adds complexity to the engine, it greatly reduces wear on engines that experience a high amount of idling or low RPM use. Through this system, oil pressure can be kept consistent at varying engine speeds so an engine at idle can retain the same amount of oil pressure that an engine under load would have. In order to prevent common issues with a dry sump system, piston oilers and an oil vapor sensor on the valve train regulate the scavenge pump to ensure that the valve train is not starved of oil due to the excess removal of oil vapors. The cooling system also includes an additional electric water pump in order to supplement the chain driven water pump the engine already utilizes. This variable phase extra pump provides additional cooling by maintaining a steady coolant pressure regardless of engine speed. Through the variable phase system, the pump can increase or reduce its output as it detects the pressure increasing or decreasing as primary water pump fluctuates with engine speed. It can even shut off entirely in order to reduce load on the vehicle's electrical system.

An option to order just the pump system for systems going on vehicles equipped with APUs and/or equipped with the cold weather package enables the use of a traditional heater core and the cold weather electrical engine heating systems.

Models

Model	Engine code	Displacement	Fuel	Output
FSLD	FSLD-PA	10.5	Diesel	650 hp, 1300 lb/ft
	FSLD-PB			750 hp, 1600 lb/ft
	FSLD-PC			860 hp, 1950 lb/ft
	FSLD-PD			1010 hp, 2010 lb/ft
	FSLD-PE			1200 hp, 2500 lb/ft
	FSLD-PF			1500 hp, 3100 lb/ft

Export models

Model	Name	Displacement	Fuel	Output
F-series Arcadie	FSLD-PG(A)	10.5	Diesel	1300 hp, 1700 lb/ft

FSLD Production G (FSL-PG)

Production variant for Arcadie tuned to 1300 hp and 1700 lb/ft of torque. The G was shipped without provisions for an air conditioning compressor or heater core in the cooling system since the engine was designed to be paired with an auxiliary power unit aboard typical military vehicles. Shipped with provisions for mounting a condenser in front of the radiator for easier integration. Operations in Arcadie rarely experience subzero conditions, so additional equipment includes only the block heater and additional insulation.

FSLH

Model	Engine code	Displacement	Fuel	Output
FSLH	FSLH-PA	10.5	Hydrogen fuel cell	250 hp, 1250 lb/ft
	FSLH-PB			450 hp, 1450 lb/ft
	FSLH-PC			550 hp, 1750 lb/ft
	FSLH-PD			650 hp, 2150 lb/ft