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Old 07-15-2024 | 09:17 PM
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-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
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Old 07-15-2024 | 10:02 PM
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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!
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Old 07-16-2024 | 12:01 AM
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Maybe the pump died because of a bad regulator giving 60 psi and the pump had to work hard and just overheated.
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Old 07-16-2024 | 06:28 AM
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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.
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