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2002 496 HO idles fine, runs up to around 3K fine, after that…

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2002 496 HO idles fine...
2002 496 HO idles fine, runs up to around 3K fine, after that under load or higher revs the engine bucks and kicks, and even cuts out as if gas is tricklng in. If I lower revs it runs nd idles fine: clogged boost pump filter or water in gas ??
Submitted: 3 years ago.Category: Boat
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Answered in 1 day by:
5/6/2015
Marine Mechanic: Joe, Marine Mechanic replied 3 years ago
Joe
Joe, Marine Mechanic
Category: Boat
Satisfied Customers: 7,580
Experience: ASE, electronics, Marine mechanical and electronics, pwc, wiring, all around repair tech,
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Hello,

Thank you for allowing me to assist you, my name is ***** ***** I will be happy to assist you with your concern today.


With the symptoms I would start with a fuel pressure test, not just key on engine off, we are talking also running at idle and also during the problem to see if your loosing fuel pressure. In terms of checking for water in fuel simply remove your spin on filter and dump contents into a glass jar allowing time to settle, if there is any water you will see the seperation between the fuel and water, but know that water in the fuel is often present at all rpm's. You would also want to check for misfires, timing, compression. You would also want to go ahead and preform a tune up, plugs, cap, rotor, fuel filter, etc.

If needed with the above info we can continue with diagnosis.

Thank you!

- Joe

Please rate my answer when ready. Bonuses are appreciated.

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I'd be happy to answer any other questions you have even if not related.

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