Cummins B Series engine
The Cummins B Series is a family of diesel engines produced by American manufacturer Cummins. In production since 1984, the B series engine family is intended for multiple applications on and off-highway, light-duty, and medium-duty. In the automotive segment, it is best known for its use in school buses, service buses in the United Kingdom and Dodge/Ram pickup trucks.
Since its introduction, three generations of the B series engine have been produced, offered in both inline-four and inline-six configurations in multiple displacements.
General engine features
The B-series features engine bores machined directly into the block. It was also set apart by the use of a shallow one-piece head, requiring closer tolerances than in other Cummins products. The engine was first manufactured in Rocky Mount, North Carolina, and other plants were later added in Mexico, Turkey, and Darlington, UK.Every Cummins powered Dodge Pickup has come equipped with a turbocharger. It uses a gear-drive camshaft for extra reliability. Also specified is a deep-skirt engine block and extra-strong connecting rods. A Holset turbocharger is used. The original B Series was updated with 24 valves and an electronic engine management system to become the [|ISB] in 1998.
First generation
3.9L/4BT
The 3.9L/4BT Cummins is an engine in the same family as the Cummins turbo-diesels. The 3.9L/4B is an inline four-cylinder turbodiesel that was popular for many step van applications, including bread vans and other commercial vehicles. Additionally it has seen broad usage in agricultural equipment. It has also gained popularity as an engine swap into smaller trucks. The lowest powered 4B produces.6BT
The 6BT, also known as the Cummins "12-valve" was the first member of the "B" engine family to be used in a light truck vehicle. The 6BT used Bosch fuel systems, injector, and VE rotary pump and P7100 inline injection pumps. Some early 6BTs were supplied with CAV rotary pumps instead, before the Bosch system became the sole standard. This engine started life in 1984 designed as an agricultural engine, for use in Case agricultural equipment.After 1989, the 6BT engine was used in light duty, medium duty and select heavy duty trucks and buses. The 6BT engine has recently become very popular for use in repowering various vehicles, in the UK they have proven very popular in the Land Rover community, commonly known as the ‘good’ conversion.
Appearing in the 1989–1998 Dodge Ram pickup truck, it became a popular alternative to the large gasoline V8 engines normally used in full-size pickup trucks, since it produced the torque at low engine speeds, and significantly better fuel mileage. During that time, the Dodge Ram was the only diesel pickup that did not rely on glowplugs for cold weather starting.
ISB 5.9
| More Details |
| 5.9-liter ISB Cummins Production: 1998.5–2007 Camshaft drive: Gear driven Crankshaft: Forged steel, 7 main bearings System capacity with filter: Fuel system: Common rail High pressure direct injection, symmetrical combustion chamber Management: Bosch Mechanical with electronic advance Power output: at 2900 rpm Torque: at 1600 rpm Compression ratio: 17.2:1 Emissions control: Electric fuel control |
The ISB is one of the largest straight-six engines used for light truck vehicles and school buses, and the improved high output 600 version was on the Ward's 10 Best Engines list for 2004.
One unusual feature of the ISB is that it is a multi-valve pushrod engine design, with 4 valves per cylinder. The engine displaces, with a cylinder bore and piston stroke. A turbocharger is used to increase the output in the high-compression diesel. It is an all-iron engine with forged steel connecting rods, an assembled camshaft, and a cast aluminum intake manifold. The engine is produced in Columbus, Indiana.
The ISB uses electronically controlled Bosch fuel systems, unlike the 6BT systems which were mechanical. Early ISB engines utilize Bosch injectors and a Bosch VP44 high pressure pump. Later ISB designs have common rail fuel injection, Bosch injectors, and a Bosch CP3 high pressure pump.
QSB
The QSB is the off-road, heavy duty version of the ISB. Typically used in marine, agricultural, and construction applications, these engines share many of the same parts as the ISB and utilize the same Bosch fuel system.Dodge Ram ISB
Midway through model year 1998, the Dodge Ram switched from the 6BT to the ISB to meet updated emissions requirements. Like other ISB's, these engines started out using the Bosch VP44 rotary injection pump. The VP44 setup meant that timing and fuel could be precisely controlled, which led to cleaner emissions. However, VP44 failure rates were higher than the older P7100 injection pump. The compression ratio in these engines was 17.2:1. The 1998–2000 ISB was rated at and when equipped with the 47RE automatic transmission. The 1998–2000 ISB was rated at and when equipped with a manual transmission. For the 2001–2002 model years, a standard output and a high output ISB Cummins engine were offered. The standard output, which was the same as the previous engines was rated to and when equipped with either a manual transmission or automatic. The high output ISB was rated at and, with only a NV5600 six-speed manual transmission available. The high output engine was different in a few ways from the standard output engine; it had higher compression, powdered metal valve seat inserts, a larger flywheel, the Bosch fuel system was reworked to allow higher fuel flows, and fuel-injection timing was altered.Dodge Ram ISB CR
For the 2003 model year, the Cummins was introduced with Bosch high pressure common rail fuel injection, again increasing power output. On automatic equipped vehicles, the 47RE was upgraded internally to increase durability and torque capacity, now known as the 48RE. The 2003 rating for the Dodge truck was released at and. Midway through the 2004 model year, the Cummins 600 was introduced, producing at 2,900 rpm and at 1,600 rpm. This engine was noticeably quieter than the previous engines.ISB 6.7
| More Details |
| 6.7-liter ISB Cummins Production: 2007–present Displacement: Bore x stroke: Max power: at 2800 rpm Torque: at ~1600 rpm Compression ratio: 17.3:1 Emissions control: EGR and DPF Turbocharger: Holset Engineering Fuel system: Common rail High pressure direct injection with 7-hole injectors Camshaft drive: Gear driven Crankshaft: Forged steel, 7 main bearings Oil System capacity with filter: |
The B6.7 is the latest version of the B Series. It is currently the largest straight-six engine produced for a light duty truck. It produces and in the 2007.5 and newer Dodge 2500/3500 pickup trucks with the Chrysler-built six-speed 68RFE automatic transmission built at the Kokomo Transmission plant in Kokomo, Indiana. Engine torque is slightly reduced with the Mercedes G56 6-speed manual transmission at and. The 2007 and newer 3500 Cab & Chassis trucks only get the and version of the B6.7, whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission. As for the 2008 4500/5500 medium duty Chassis Cabs or the Sterling Bullet Trucks, they receive the and version of the B6.7, whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission. Late model 2011 Ram trucks produce and, with the exhaust brake rating boosted from to.
For 2020 this engine has been updated to produce 400hp and 1000 ft-lb torque.
Changes over the 5.9
There are many changes over the previous B5.9 for the Dodge truck, the most obvious being the larger displacement. The B6.7 had an increase of cylinder bore and piston stroke to, respectively, thereby giving a displacement of.With the 6.7 L Cummins Engine came the introduction of the Variable Geometry Turbocharger. The VGT Turbocharger was introduced to reduce turbo lag by adjusting the vanes by sliding a steel ring in the exhaust housing dependent on engine RPM creating more or less pressure inside the exhaust housing and controlling the speed of the turbocharger. It also works as an integrated exhaust brake system and is all controlled by an electronic actuator on the turbocharger. This VGT system has been an extremely common issue with the 6.7L Cummins platform and is typically diagnosed by the loss of the trucks exhaust brake.