500EFI fuel pressure questions
 

-2002 500EFI’s w/ cool fuel module and mechanical pumps drawing from the tanks
-started hearing the port fuel pump just blip on for a second during the key on prime cycle instead of running the 3-5 seconds as it always had. This didn’t happen all the time but just occasionally
​​​​​​-last Sunday it blipped on then off, engine wouldn’t start. Cycled the key again and prime cycle sounded normal, engine started right up
-thought to myself I shouldn’t go out but I did anyway
-up on plane for a couple minutes and felt the boat slow down. Looked down and that engine RPM had dropped from 3500 to around 2000. Cut the throttles back to idle
-engine never stalled and all ran fine at idle
-idled home and did some testing
-key cycle a bunch of times and all was good, prone cycle normal.
-fuel pressure was 43psi with vacuum line attached……4-5 psi higher than it should be from what I now understand.
-decided to just replace the pump with no definitive info
-replaced the fuel pump and now have 60psi at idle with or without vacuum line attached
-vacuum line is good with no holes, etc.
-starboard engine has 40 at idle with vac line attached and 43 without……my understanding is that is normal
-thinking this is telling me I have a bad regulator on the port engine ?

anyone have any suggestions or had a scenario like this?

thanks, Pat

Regulators are the cheapest part between those 2 parts
i also had fuel pump issues in the past and it was the pump and the regulator both at the same time... so yeah go shead and change it!

Maybe the pump died because of a bad regulator giving 60 psi and the pump had to work hard and just overheated.

Good points. I had been thinking I was missing something because it would be odd for both to fail at the same time but maybe that’s exactly what happened? Thanks for the feedback.