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Old 06-24-2007 | 04:35 PM
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Question 496ho fuel problem

Out boating today and docked. When leaving 1/2hr later, port motor no start. No big deal, limped back to launch and was just out checking motor. Pulled plugs....dry as a bone...pulled water seperator and it is full of gas, cycled fuel pump via the key while the hose was off of the water seperator and pump works and spits fuel. I DO NOT have factory inline fuel filters so I am wondering where do I go from here.

I did some searching here of other fuel related problems and my guess is I have a bad main pump or plugged somewhere. I did pull the cowling and pressed the schader valve on the fuel rail and I have fuel there (came squirting out).

The fuel cooler/pump looks extremely difficult to get at and remove.

How difficult is it to remove the injectors..any advice.

Thanks in advance!

Jeff
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Old 06-25-2007 | 11:24 AM
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Pull the booster pump. Alum. 6" long behind seperator. Screen will be clogged with crap. 1 hr or less. Just did it again last week and it was packed. JC
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Old 06-25-2007 | 12:08 PM
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Jeff, sent ya PM on cleaning the injectors.

To verify the boost pump thoroughly, you will need to do a pressure test on the fuel rail. Should be between 38-43 psi. I had one on each engine die last year within weeks of each other. When bad they will start in the mid 30 psi, then drop quick to around 20-25 making the motor run like crap and die. But you'll still get a little spurt of gas from the hose.

Pour your separator fuel into a jar or glass bowl and allow to sit for awhile, then check the fuel's condition if not already.

Clean the boost pump screen as suggested. Then clean the injectors as I described in the PM.

Start the engine and begin to feel around the exhaust manifolds to see that each cylinder is warming up (firing) nicely, otherwise a dead plug or wire.

The simple simon approach to the process of elimination is to keep in mind the three things a motor needs: Combustion/compression, fuel, and ignition.

Barring a sensor gone bad which you need a scantool to check, or and alrm (which typically fuel issues won't trigger) it's most likely fuel thanks to the Ethanol craze.

Good luck.
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Old 06-26-2007 | 08:03 AM
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Sounds like a better fuel filter in the gas feed line is needed to catch the crap before it gets to the boost pump?
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Old 06-26-2007 | 09:15 AM
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The inline wasn't there in the first production models. it came later after some fuel issues.

Problem is they only catch the really large chunks of crap and pass the small stuff that can damage/clog the boost or injectors.

In the manual it says not to install any after market filters because the system is designed to flow properly on the current design? The main problem is the fuel doesn't hit another filter except a screen, until it already passes thru the fuel boost pump THEN to the separator.

You just have to keep an eye on the fuel's condition, and change spearators more frequently, and add additives such as Pri-G, StarTron, and Stabil.
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