by JP
(Possum Kingdom Lake, TX)
The engine Can't maintain an idle. Prior to my current issue, the high pressure pump was running extremely hot. So to avoid failure in the middle of the lake unexpectedly, I replaced the entire fuel pump assembly (High & Low pressure pump).
Upon replacing the pump system, I ran the boat for about 5 minutes then turned it off. The next day I took the boat out for about a 12 minute trip to the public boat ramp (of which about 4 minutes were idling thru a no wake zone and the remainder was running about 80% full throttle). During both of these post pump replacements run times it ran beautifully
Once at the boat ramp area I turned off the engine and haven't been able to start it since. I tried while it was warm and then 2 weeks later tried again when everything was cold.
The engine tries to run but won't hold an idle. I've tried with and without using the throttle, when pumping the throttle but it gives a sucking sound and stalls the semi idle every time.
Prior to replacing the fuel pump assembly, everything appeared and sounded to run well, except the pump was too hot to touch and made a fairly high pitched sound similar to an emergency siren. The volume of the sound was not overly obnoxious but noticeable if you know normal engine sounds. Additionally, this is a fuel injected system.
Your thoughts? How do I test the new pump for proper operation?