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scotthebco
08-15-2011, 01:44 PM
I just put 2 new fule filters in the boat and it runs great, but whenI try to push the boat past 33 mph, the boat won't go any faster. I am only pushing throttle to about 80% of the full range, but the boat seems to be at top speed. Any replies are greatly appreciated. I am wondering if I have fuel pump issues.

Thanks,

Scott Stafford

02ProstarSammyD
08-15-2011, 02:13 PM
Grab a pressure gauge and test it on the water. Should be a shraeder valve you can screw right into

scotthebco
08-15-2011, 02:24 PM
Thanks for the repsponse. What kind of pressure should I be looking for?

Thanks!

02ProstarSammyD
08-15-2011, 02:27 PM
What engine?

TxsRiverRat
08-15-2011, 02:32 PM
more than likely the 350 chebby mang

02ProstarSammyD
08-15-2011, 02:53 PM
Mine is a merc 3 fifty and its 43 psi I believe. Maybe someone else can chime in on that one. Is this a consistent problem or only happened 1 trip? Regardless when you pressure test you will see the problem. Most of the times if the pump has inconsistent power or is dying it will flutter all over the place. My system is alil different b/c I have 2 external electric pumps as opposed to the intank stock mc pumps.

scotthebco
08-15-2011, 03:21 PM
Thanks For the responses. IT is the stock EFI Vortec with the Hurth transmission I believe. The boat runs consistently, but it will not run any higherthan the 33 to 35 mph. I will look at the rpm's when I take it out next time.

snobinge
08-15-2011, 03:38 PM
We had an issue last summer with our 98 205(330 hrs). It would have no power on the bottom. Our issue was one of the electronic modules on top of motor.

mtrask
08-15-2011, 05:09 PM
I would check under the rear engine mount for the other fuel filter, which is were i found my trouble in my "97". Good Luck

scotthebco
08-15-2011, 08:55 PM
Thanks for your response. I was able to change both fuel filters. I did have to replace the aluminum ball valve from the tank to the first fuel filter. I bought a brass transistion fitting from JIC to MIP. With some fuel grade pipe sealant, the boat runs fine, but no more power at the high end. I also wonder if it could be a clogged fuel injector.

JDK
08-15-2011, 09:13 PM
If you're fuel pump is on the back of the engine, remove it and clean the screen that's inside the inlet (from tank) fitting.

mtrask
08-15-2011, 09:21 PM
What motor? I had the LT1
Check the Fuel Pressure.
Is there a whining coming from the fuel pump? When I had supply trouble with that pump, meaning my filter was clogged, the pump whined. Ultimately the pump was cavitating or not getting the proper amount of fuel.

Jim@BAWS
08-15-2011, 09:23 PM
Mine is a merc 3 fifty and its 43 psi I believe. Maybe someone else can chime in on that one. Is this a consistent problem or only happened 1 trip? Regardless when you pressure test you will see the problem. Most of the times if the pump has inconsistent power or is dying it will flutter all over the place. My system is alil different b/c I have 2 external electric pumps as opposed to the intank stock mc pumps.


Are you sure?? Did you boat some out of Disney World... The only Mercrusiers I know in a MC came from Sammy's School in Disney



Jim@BAWS

scotthebco
08-15-2011, 09:30 PM
Wow! My fuel pump does make a high pitch squeal. I haven't cleaned the screen that does make sense. Thanks for the all the help. Really appreciate it. How do you clean the screen?

mmthorn
09-03-2011, 09:07 PM
Did you fix your problem?