A cooling system for turbocharger mechanisms for the purpose of cooling the turbocharger mechanism ‘when the vehicle engine has been shut off, thus preventing
damage which may result from residual heat in the turbocharger. The system includes an auxiliary pump and conduits bypassing the engine oil pump, the auxiliary pump being controlled in part in its operation by a temperature responsive switch installed in the exhaust portion of the turbocharger. The temperature responsive switch is in an electric circuit with a pressure responsive switch operated 'by the engine oil system, the arrangement being such that the auxiliary pump will operate when the engine is shut off as long as an elevated temperature exists in the turbocharger mechanism.