Cummins Engine Lubricant Qualification Tests

Cummins ISB Test Method:

• The Cummins ISB test method is a 350-h 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-h in two stages. During the 100 h stage A, the engine is operated with retarded fuel injection timing to generate excess soot. During the 250 h 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-h period for the first 100-h of the test. Thereafter, oil samples are taken every 50-h. Oil additions are not made during the last 250-h 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 was developed to assess the performance of an engine oil 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.