I agree your #4 test was not conclusive enough. Fuel shutoff should occur almost instantly when vacuum stops.
There are several parts in that petcock diaphragm assembly -- a spring, a piston (correct name is fuel valve) and the rubber itself -- the malfunctioning or weak operation of any one of which could cause sluggish operation, such as the piston only partially closing, or sometimes maybe not closing at all. All the other symptoms you describe (happening south of the petcock) are directly related to fuel flowing when and where it's not supposed to. -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en.
