QSB Marine Engine QSB Marine Engine Basic FeaturesBasic Features

Metric Horsepower vs. SAE HorsepowerMetric Horsepower vs. SAE Horsepower

The difference between ISO 8665 fuel stop power (bhp) and The difference between ISO 8665 fuel stop power (bhp) and Metric Horsepower (PS) as presented in Cummins Marine Metric Horsepower (PS) as presented in Cummins Marine literature is described below.literature is described below.

To compare Cummins Marine engines with sales literature To compare Cummins Marine engines with sales literature for some competitive marine engines, the Cummins Marine for some competitive marine engines, the Cummins Marine Products Guide and Technical Publications presents some Products Guide and Technical Publications presents some recreational marine propulsion ratings in metric power.recreational marine propulsion ratings in metric power.

The PS values are greater than the bhp rating.The PS values are greater than the bhp rating.

However, the increase is not solely a function of the However, the increase is not solely a function of the conversion to PS.conversion to PS.

The derivation of the PS rating as depicted in Cummins The derivation of the PS rating as depicted in Cummins Marine literature warrants an explanationMarine literature warrants an explanation..

Metric Horsepower is power in units of Pferdestarke (PS), Metric Horsepower is power in units of Pferdestarke (PS), and one ISO Horsepower equates to 1.0143 PS. and one ISO Horsepower equates to 1.0143 PS.

The PS values presented include the conversion from The PS values presented include the conversion from bhp to PS as well as a 3 percent increase for fuel bhp to PS as well as a 3 percent increase for fuel temperature adjustment.temperature adjustment.

The bhp values presented here were calculated through The bhp values presented here were calculated through engine dynamometer testing according to ISO 8665 fuel engine dynamometer testing according to ISO 8665 fuel stop power with a fuel temperature of 40stop power with a fuel temperature of 40ooC (104C (104ooF). F).

However, to be comparable with other manufacturers, PS However, to be comparable with other manufacturers, PS values were calculated and power corrected for a fuel values were calculated and power corrected for a fuel temperature of 25temperature of 25ooC (77C (77ooF).F).

The 15The 15ooC (27C (27ooF) fuel temperature differential has a F) fuel temperature differential has a significant affect on fuel density (lb/gal).significant affect on fuel density (lb/gal).

As fuel temperature is lowered, density, and energy As fuel temperature is lowered, density, and energy content (Btu/lb) of the fuel increase. content (Btu/lb) of the fuel increase.

The combination of conversion from bhp to PS, the adjustment for The combination of conversion from bhp to PS, the adjustment for lowered fuel temperature, and rounding of the number, equate to lowered fuel temperature, and rounding of the number, equate to the Metric Horsepower value advertised. the Metric Horsepower value advertised.

The table below details the conversion.The table below details the conversion.

Bhp to PS Fuel Temperature Metric HpFactor Adjustment Factor Rating

Engine Model kW bhp 1.0143 1.03 Advertised *4BT3.9-M 155B 112 150 152.1 156.7 155

4BTA3.9-M 4B-250 179 240 243.4 250.7 2506BT5.9-M 220B 157 210 213.0 219.4 220

6BTA5.9-M 270B 194 260 263.7 271.6 270" " 330B 235 315 319.5 329.1 330" " 370B 265 355 360.1 370.9 370

6CTA8.3-M 450C 321 430 436.1 449.2 450" " 480 C-E 343 460 466.6 480.6 480

* Advertised Metric Horsepower = bhp X 1.0143 X 1.03

ISO 8665

Bosch Common Rail Fuel Bosch Common Rail Fuel SystemSystem Bosch Common Bosch Common

Rail Fuel SystemRail Fuel SystemNon-wastegated Non-wastegated

TurbochargerTurbocharger

Heat Heat ExchangerExchanger

Standard B Standard B Marine MountsMarine Mounts

Belt Driven Belt Driven Sea Water Sea Water

PumpPump

Low Profile Low Profile Expansion TankExpansion Tank

Tone Wheel for Tone Wheel for Primary Engine Speed Primary Engine Speed

SensorSensor

Accessory Drive Accessory Drive Pulley Available for Pulley Available for

Mounting to the Mounting to the CrankshaftCrankshaft

Bosch Common Rail Fuel Bosch Common Rail Fuel SystemSystem

Remote Mount Remote Mount Fuel Filter Fuel Filter

(2 Micron)(2 Micron)

Automatic Belt Automatic Belt TensionerTensioner

Remote Mount Remote Mount Oil FilterOil Filter

AlternatorAlternator

Water Pump Water Pump Inlet TubeInlet Tube

The QSB offers a front power take-off adapter (FPTO). It may be The QSB offers a front power take-off adapter (FPTO). It may be used to take power off the front of the engine in flexible and solid used to take power off the front of the engine in flexible and solid mount engine installations.mount engine installations.

Fracture-Split Connecting RodsFracture-Split Connecting Rods

The connecting rod design continues to be an angle-split rod: The connecting rod design continues to be an angle-split rod: however, the surface between the connecting rod and the cap is no however, the surface between the connecting rod and the cap is no longer machined. A process known as “fractured splitting” detaches longer machined. A process known as “fractured splitting” detaches the connecting rod cap from the connecting rod. The cap is separated the connecting rod cap from the connecting rod. The cap is separated utilizing a high-momentum force, resulting in a unique surface on utilizing a high-momentum force, resulting in a unique surface on every connecting rod cap.every connecting rod cap.

The surface of the connecting rod and cap must be protected The surface of the connecting rod and cap must be protected against damage: the cap and rod must be assembled before against damage: the cap and rod must be assembled before performing any cleaning. Any damage to the fractured surface will performing any cleaning. Any damage to the fractured surface will result in an improper torque on the connecting rod capscrews. When result in an improper torque on the connecting rod capscrews. When replacing the connecting rods, replace with the same part number replacing the connecting rods, replace with the same part number (or superceding part number) of the rod that was removed.(or superceding part number) of the rod that was removed.

Block StiffenerBlock Stiffener

The engine is equipped with a block stiffener plate that is located on The engine is equipped with a block stiffener plate that is located on the bottom deck of the engine block. The stiffener plate is held in the bottom deck of the engine block. The stiffener plate is held in place with several capscrews around its perimeter. The stiffener place with several capscrews around its perimeter. The stiffener provides additional support to the lower portion of the block.provides additional support to the lower portion of the block.

Head GasketHead Gasket

The cylinder head gasket is a multi-layer steel gasket that is graded The cylinder head gasket is a multi-layer steel gasket that is graded to two different thicknesses. To maintain proper cylinder pressure to two different thicknesses. To maintain proper cylinder pressure when replacing the gasket, make sure the new gasket is the same when replacing the gasket, make sure the new gasket is the same part number as the one being replaced. Alternatively, consult the part number as the one being replaced. Alternatively, consult the T&R manual for instructions on how to measure for the proper T&R manual for instructions on how to measure for the proper gasket. Because the gasket is graded, graded pistons are no longer gasket. Because the gasket is graded, graded pistons are no longer used.used.

The QSB engine does not offer a direct drive option. The sea water pump The QSB engine does not offer a direct drive option. The sea water pump is belt driven. For installations that utilize a keel cooler, the pulley that is belt driven. For installations that utilize a keel cooler, the pulley that would normally drive a sea water pump will be available to drive an would normally drive a sea water pump will be available to drive an accessory pump.accessory pump.

Sea Water Sea Water PumpPump

Single Groove Single Groove PulleyPulley

Belt Adjustment Belt Adjustment ScrewScrew

The QSB engine utilizes a heat exchanger that is common to the 450C/430C The QSB engine utilizes a heat exchanger that is common to the 450C/430C engine today. The heat exchanger is a shell and tube type and the engine today. The heat exchanger is a shell and tube type and the expansion tank is fabricated.expansion tank is fabricated.

Heat Heat ExchangerExchanger

Expansion TankExpansion Tank

LTA System OperationLTA System Operation

1.1. At start-up the coolant is cold and the At start-up the coolant is cold and the thermostat is closed. All coolant flow thermostat is closed. All coolant flow is by-passing the keel cooler while the is by-passing the keel cooler while the thermostat is closed.thermostat is closed.

2.2. As the engine begins to warm up, the As the engine begins to warm up, the thermostat begins to open. As the thermostat begins to open. As the thermostat opens, coolant is directed thermostat opens, coolant is directed to the keel cooler. Coolant that flows to the keel cooler. Coolant that flows through the keel cooler is returned through the keel cooler is returned back to the thermostat housing where back to the thermostat housing where it is mixed with the main flow going to it is mixed with the main flow going to the aftercooler.the aftercooler.

QSB Single Loop LTA Coolant Flow DiagramQSB Single Loop LTA Coolant Flow Diagram

The QSB engine is available with an SAE #3 flywheel/housingThe QSB engine is available with an SAE #3 flywheel/housing

Flywheel Flywheel HousingHousing

Fuel SystemFuel System

A primary fuel water separator with a 10 micron rating and a drain valve must A primary fuel water separator with a 10 micron rating and a drain valve must be installed between the engine and the fuel tank.be installed between the engine and the fuel tank.

A water in fuel (WIF) sensor must be installed with the primary fuel water A water in fuel (WIF) sensor must be installed with the primary fuel water separator and it must be connected to the ECM.separator and it must be connected to the ECM.

Racor Primary Fuel Racor Primary Fuel Filters Filters

(10 Micron)(10 Micron)

Open Crankcase VentilationOpen Crankcase Ventilation

Crankcase VentilationCrankcase Ventilation

Closed crankcase ventilation Closed crankcase ventilation systems are approved for the systems are approved for the QSB if they are ordered with QSB if they are ordered with the engine and assembled by the engine and assembled by CMD. They are not approved as CMD. They are not approved as aftermarket installations.aftermarket installations.

QSB Marine Engines use a non-wastegated turbocharger. QSB Marine Engines use a non-wastegated turbocharger. The exhaust housing is water cooled by engine jacket The exhaust housing is water cooled by engine jacket water.water.

Non-Waste Gated Non-Waste Gated Coolant Cooled Coolant Cooled TurbochargerTurbocharger

QSB Marine Engine Coolant QSB Marine Engine Coolant System FeaturesSystem Features

Jacket Water Jacket Water PumpPump

The output from the Jacket Water Pump empties into the side of the oil The output from the Jacket Water Pump empties into the side of the oil cooler cavity of the cylinder block. cooler cavity of the cylinder block.

This provides the oil cooler with the coolest possible coolant.This provides the oil cooler with the coolest possible coolant.

A small passage from the bottom of the oil cooler cavity allows some A small passage from the bottom of the oil cooler cavity allows some coolant to return to the suction side of the water pump to ensure coolant to return to the suction side of the water pump to ensure constant coolant flow around all areas of the oil cooler core.constant coolant flow around all areas of the oil cooler core.

The coolant thermostat is located in the cylinder head The coolant thermostat is located in the cylinder head near the front of the head on the exhaust side of the near the front of the head on the exhaust side of the engine.engine.

The water outlet installs over the thermostat. The coolant The water outlet installs over the thermostat. The coolant temperature sensor mounts into the cylinder head.temperature sensor mounts into the cylinder head.

Coolant Coolant Temperature Temperature

SensorSensor

Water Cooled Exhaust Water Cooled Exhaust ManifoldManifold

Turbo Coolant Turbo Coolant return to Water return to Water

PumpPump

Turbo Oil Drain LineTurbo Oil Drain Line

Heat Heat ExchangerExchanger

Turbo Oil Feed LineTurbo Oil Feed LineECM and ECM and

Cooling PlateCooling Plate

BulletinBulletin Title of PublicationTitle of Publication

40212714021271 Troubleshooting and Repair Manual, ISB e and ISB Troubleshooting and Repair Manual, ISB e and ISB (Common Rail Fuel System)(Common Rail Fuel System)

40213374021337 Troubleshooting and Repair Manual, CM850 Electronic Troubleshooting and Repair Manual, CM850 Electronic Control System, ISB EnginesControl System, ISB Engines

36664833666483 ISB with CM850 Engine Control Module Wiring DiagramISB with CM850 Engine Control Module Wiring Diagram33790003379000 Air for Your Engine BulletinAir for Your Engine Bulletin33790013379001 Fuel for Cummins Engine BulletinFuel for Cummins Engine Bulletin33872663387266 Cold Weather Operation BulletinCold Weather Operation Bulletin36661323666132 Cummins Coolant Requirements and Maintenance BulletinCummins Coolant Requirements and Maintenance Bulletin40213554021355 Owner's Manual - ISB e and ISB (Common Rail Fuel System) Owner's Manual - ISB e and ISB (Common Rail Fuel System)

Series EnginesSeries Engines36664963666496 Operation and Maintenance Manual - Current ISB e and ISB Operation and Maintenance Manual - Current ISB e and ISB

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