Development of the PSA TU‐3 test for valve train scuffing wear

Abstract

The development of the valve train scuffing wear test by the CEC PL‐35 group is described. This test is run on the PSA TU‐3 engine, comprises a cold/low speed and a hot/high speed phase and is of 100 h duration. Oil performance is evaluated in terms of camshaft wear and follower contact pad scuffing merit rating. Studies undertaken by the group to identify those factors essential to the control of test development are described. The evolution of the test, with the introduction of a single point fuel‐injected engine, is detailed and the consequences of this on severity and repeatability and reproducibility are discussed.