N14 Base Engine Troubleshooting and Repair Manual – 014-003   Engine Run-in (Chassis Dynamometer)

Refer to Chassis Dynamometer Operation, Procedure 014-002-011, for general operating procedures and safety precautions.

Operate the vehicle in a gear that produces a road speed of 90 to 100 km/h [55 to 60 mph] at maximum horsepower rpm.

Install a Cummins electronic service tool on CELECT™ and CELECT™ Plus engines for monitoring engine performance variables, system pressures, temperatures, etc.

Monitor and record the following measurements during run-in:

• Lubricating oil pressure
• Coolant temperature
• Fuel pressure
• Engine Torque
• Crankcase Blowby
• Engine speed (rpm)
• Fuel rate (use fuel measuring device, Part No. 3376375)
• Intake manifold air temperature
• Intake manifold pressure
• Turbocharger inlet air temperature
• Oil temperature

Refer to the Engine Dynamometer Worksheet in this section.

Cummins Engine Company, Inc. recommends monitoring block coolant pressure during run-in to aid in early indication of a cooling system problem.

Obtain the CPL number from the engine dataplate and the fuel pump code from the fuel pump dataplate.

Engine performance specifications and fuel system calibration values are listed for specific engine CPL and fuel pump codes in the following publications:

1. Fuel Pump Calibration Values, Bulletin No.

   3379352.

2. Injector Parts Flow and Cross Reference, Bulletin No.

   3379664.

3. Engine Data Sheets

During the test, if a sudden increase in blowby occurs or if blowby exceeds the maximum allowable limit during any run-in, return to the previous step and continue the run-in. If blowby does

not
reach an acceptable level during the next step, discontinue the run-in and determine the cause.

Do

not
proceed to the next step until a steady, acceptable blowby reading is obtained.

NOTE: Blowby

must
be measured by using blowby checking tool, Part No. 3375150 or 3822566 with a manometer, Part No. ST-1111-3, or its equivalent. Blowby checking tool, Part No. 3375150, as shown, utilizes a chamfered 7.67 mm [0.302 in] orifice.

Move the throttle to obtain 1200 rpm engine speed, and apply a test load sufficient to develop 25 percent rated fuel pressure on STC engines or 25 percent fuel rate on CELECT™ and CELECT™ Plus engines.

Operate the engine at this speed and load level until the coolant temperature reaches 70°C [158°F].

Check all gauges and record the data.

Operate the engine at maximum horsepower rpm and 75 percent of rated fuel pressure on STC engines or 75 percent fuel rate on CELECT™ and CELECT™ Plus engines for 3 minutes. Check the gauges, and record the readings.

NOTE: Do

not
proceed to the next step until a steady, acceptable blowby reading is obtained.

Operate the engine at maximum horsepower rpm and advertised horsepower with a wide open throttle for 5 minutes. Check the gauges, and record the readings.

Operate the engine at nominal torque peak rpm, full load, and wide open throttle for 5 minutes. Check the gauges, and record the readings.

Refer to the engine “Data Sheet” for the torque peak rpm of the engine model being tested.

Operate the engine at maximum horsepower rpm and advertised horsepower with a wide open throttle for 5 minutes. Check the gauges, and record the readings. Compare the readings to those published on the appropriate engine “Data Sheet”.

CAUTION  Do not shut off the engine immediately after the run-in is completed. Allow the engine to cool by operating it at 700 to 900 rpm for a minimum of 3 to 5 minutes to avoid internal component damages. This allows the turbocharger and other components to cool.

Shut off the engine.

Make sure all instrumentation is removed before removing the vehicle from the chassis dynamometer.