Flushing Port-Exhaust Housing

Evinrude E-Tec 150-E150DPXSE-Serial # 05162249-2007

Evinrude-E-Tec-40-E-40DRLSO-Serial # 05095456-2005

Since Evinrude don’t have a quick disconnect for the E-Tec’s I purchased a regular garden hose quick disconnect. Back in 2005 my E-Tec-40-E-40DRLSO rubber flushing port fell off and sank in the alongside water.

Today while on my boat the Evinrude E-Tec 150-E150DPXSE rubber flushing port started coming off. Is there a secret in putting the rubber flushing port back on? Maybe use a thin 2-inch putty knife or a special tool? Any help would be appreciated