Vacuum brake assist

[LUCKY13]

Can anyone tell me the best way to test if the vacuum powebrake assist is working properly on my 65?

 

[IH2LOSE]

I am pretty sure its just a matter of turning off the car, and then disconnecting the connector that goes into the rubber bushing ,as long as you hear the release of the vacuum its good, If no vacuum release then something is a miss

Now just make sure its not something other then the booster as in a kinked or cracked hose not getting vacuum to the booster