Providing Wear Protection for Flat-Tappet (Sliding) Camshaft Followers in Rebuilt Engines

摘要

Rebuilt engine "break-in" is the most critical period for long-term durability for a flat-tappet valvetrain. Zinc dialkyl dithio phosphate (ZDDP) has proven to be a cost-effective engine oil additive for anti-wear protection and oxidation resistance. But, tightening exhaust emission standards are requiring modern lubricants to have reduced levels of ZDDP additives. If the valvetrain break-in is successfully completed, then modern low-phosphorus lubricants can be used with confidence at subsequent oil change service intervals.