Assertion: lubricant | /r/CapableOf | protect the valve train
Facets:
value: at startup
type: LOCATION
value: in a car engine
type: LOCATION
Source sentences:
text: Lubricants may contain polar additives known as friction modifiers that chemically bind to metal surfaces to reduce surface friction even when there is insufficient bulk lubricant present for hydrodynamic lubrication, e.g. protecting the valve train in a car engine at startup.