CM850 Electronic Control System - 018-016 Fuel System

For performance and fuel rate values, refer to the Engine Data Sheet or the fuel injection pump for the particular model involved.

Engine Idle Speed
– ISB/QSB	Minimum 600 to maximum 800 rpm
Maximum Fuel Inlet Restriction
– ISB Automotive (to lift pump)	20.3 kPa [6 in Hg]
– QSB Marine (to lift pump)	14 kPa [4 in Hg]
– ISC/QSC – Dirty Filter (OEM connection point)	27.0 kPa [8 in Hg]
Maximum Fuel Inlet Restriction (gear pump inlet)
– ISB/QSB
– Automotive and Industrial	20.3 kPa [6 in Hg]
– ISC/QSC	33.9 kPa [10 in Hg]
Maximum Fuel Inlet Temperature
– ISB/QSB
– Automotive and Industrial	70°C [158°F]
– Marine	60°C [140°F]
Fuel Pressure Range at Fuel Filter Outlet (engine cranking)
– ISB/QSB	0.0 to 79.9 kPa [0.0 to 11.6 psi]
Fuel Pressure Range at Fuel Filter Inlet (engine running)
– ISB/QSB	0.0 to 79.9 kPa [0.0 to 11.6 psi]
Maximum Pressure Drop across Fuel Filter
– ISB/QSB	34 kPa [5 psi]
– ISC/QSC/ISL/QSL	138 kPa [20 psi]
Rail Pressure
– ISB/QSB
– Automotive and Industrial	250 to 1600 bar [3626 to 23,206 psi]
– Marine	250 to 1440 bar [3626 to 20,885 psi]
Maximum Fuel Drain Line Restriction
– ISB/QSB
– Automotive and Industrial	19 kPa [2.7 psi]
– Marine	14 kPa [2 psi]
– ISC/QSC	254 mm Hg [10 in Hg]
Minimum Gear Pump Pressure (during cranking)
– ISC/QSC	69 kPa [10 psi]
Minimum Lift Pump Pressure (gear pump inlet during cranking)
– ISC/QSC	34 kPa [5 psi]
Minimum Engine Cranking Speed	150 rpm

Last Modified: 07-Apr-2005

CM850 Electronic Control System – 018-016 Fuel System