Cummins Lubricant Qualification Test Methods

Cummins lubricant qualification test methods include the ISB and ISM test methods.

Cummins ISB Test Method:

The Cummins ISB test method is a 350-hour test developed to evaluate the durability and reliability of the camshaft and tappet interface when run with different lubricating oils. The test method utilizes a modern medium-duty diesel engine equipped with exhaust gas recirculation. The test method uses a 2004 EPA emission compliant Cummins 5.9L ISB diesel engine. Test duration is 350 hours in two stages. During the 100 hour stage A, the engine is operated with retarded fuel injection timing to generate excess soot. During the 250 hour stage B, the engine is operated at cyclic conditions to induce valve train wear.

Prior to each test, the engine is cleaned and assembled with new overhead valve train components. All aspects of the assembly are specified. A forced oil drain, an oil sample, and an oil addition are performed at the end of each 25-hour period for the first 100 hours of the test. Oil samples are taken every 50 hours. Oil additions are not made during the last 250 hours of the test cycle. Oil performance is determined by assessing crosshead wear, tappet weight loss, and cam profile wear at 3.25% soot.

Cummins ISM Test Method:

The Cummins ISM test method assesses the performance of engine oils, to control engine wear and deposits under heavy-duty operating conditions selected to accelerate soot generation, valve train wear, and deposit formation in a turbocharged, after cooled four-stroke-cycle diesel engine equipped with exhaust gas recirculation hardware. This test method uses a 2002 Cummins ISM diesel engine. Test duration is 200 hours in four 50-h stages. During stages 1 and 3, the engine is operated with retarded fuel injection timing and is over fueled to generate excess soot. During stages 2 and 4, the engine is operated at conditions to induce valve train wear.

Cummins COP Test Method:

The Cummins Oxidation and Power Cylinder (COP) Test assesses the performance of engine oils to control oxidation, engine wear and deposits in a 2018 Cummins ISX12N natural gas engine under heavy-duty operating conditions selected to accelerate oxidation, power cylinder wear and deposit formation. The engine is a turbocharged, after cooled four-stroke, spark-ignited, natural gas engine equipped with exhaust gas recirculation hardware and three-way after treatment catalyst. Test duration is 400 hours. This test is required to receive Cummins CES 20092 natural gas engine oil approval.