Abstract: “Valves used in passenger car engines, running on gasoline, operate in a very hostile environment that is characterized by high temperatures and pressures, impact loading, thermal stresses, and fatigue loading. These engines, when in operation, result in generation of temperatures that are close to 600ºC inside the intake valve; the corresponding value for the exhaust valve being 700°C to 800°C, respectively. However, the exhaust valve temperatures can shoot up to 950°C for a retrofitted LPG – run gasoline engine. Engine valves, being subjected to such high temperature and pressures, are extremely vulnerable against wear and consequent failure. Wear failure of valves is a commonly encountered phenomenon and the fatigue crack growth has its own role to play in contributing to the failure. The wear mechanisms in valves of LPG – run retrofitted engines have been found to be a combination of oxidation and adhesive wear, though valves also fail due to surface erosion and corrosion. Since ret”

Keywords: valves, retrofitting, LPG, wear, oxidation, adhesive wear