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Discussion Starter #1
Turn key on fuel pressure comes up to 40 and then drops to 0 after power shuts off to pump with key still on. I have replaced both high and low pressure pumps changer filter. Bulb is tight

When its workingright, turn key on pressure at 40 pump turns off pressure at 40 until you turn key to crank then pressure jumps to 90 like it should.

Any ideas out their? computer says no problems with my computer. I am thinking fuel reg or check valve with trash???
 

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There's a guy named Tim at C&K marine in OB who seems to work miracles with Optimax.
 

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Turn key on fuel pressure comes up to 40 and then drops to 0 after power shuts off to pump with key still on. I have replaced both high and low pressure pumps changer filter. Bulb is tight

When its workingright, turn key on pressure at 40 pump turns off pressure at 40 until you turn key to crank then pressure jumps to 90 like it should.

Any ideas out their? computer says no problems with my computer. I am thinking fuel reg or check valve with trash???
You don't need a miracle to work on these engines. They are pretty straight forward. Sounds like one of your fuel injectors is leaking. That is assuming you don't have a visible fuel leak on the outside.

Straight out of the shop manual:
If a fuel injector or injector O-ring is leaking, fuel will enter the air pressure side of the rail.
Fuel in the air side of the rail will cause spark plug fouling. A simple test is to connect a
pressure gauge to the fuel pressure test port and turn the ignition key to the ON position.
NOTE: Prior to making this test, prime the fuel system using the primer bulb in the fuel
supply hose to confirm that the Vapor Separating Tank (VST) is filled with fuel.
• The electric fuel pumps should run for about 2 – 3 seconds.
• The fuel pressure should rise to about 275.8 – 310.3 kPa (40 – 45 psi) when the
pumps are running.
• When the pumps stop, the pressure should level off to about 137.8 –171.2 kPa (20
– 25 psi) and hold.
• If the pressure drops below 137.8 kPa (20 psi) quickly, it is an indication of a fuel
leak.
If a fuel leak is suspected, proceed as follows:
• Remove the fuel rail retainer nuts.
• Remove the water outlet hose (port rail only).
• Slide the rails away from the cylinder heads [keeping the direct injectors in place
in the cylinder heads].
• Turn the ignition key to the ON position to pressurize the system and look fuel
leaks at the injector openings.
• Replace any leaking injectors.

What color are your injectors? I have a few spare ones I may be able to sell you.
 

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Discussion Starter #5
We did get pressure to stay up after cleaning the pressure regulator that had trash. but now will not crank this is getting old quick. We did pull the port fuel rail and fired the stbd injector and had fuel flowing out of the air ports in the port rail. I am thinking o ring bad on injectors.
 

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You don't need a miracle to work on these engines. They are pretty straight forward. Sounds like one of your fuel injectors is leaking. That is assuming you don't have a visible fuel leak on the outside.

Straight out of the shop manual:
If a fuel injector or injector O-ring is leaking, fuel will enter the air pressure side of the rail.
Fuel in the air side of the rail will cause spark plug fouling. A simple test is to connect a
pressure gauge to the fuel pressure test port and turn the ignition key to the ON position.
NOTE: Prior to making this test, prime the fuel system using the primer bulb in the fuel
supply hose to confirm that the Vapor Separating Tank (VST) is filled with fuel.
• The electric fuel pumps should run for about 2 – 3 seconds.
• The fuel pressure should rise to about 275.8 – 310.3 kPa (40 – 45 psi) when the
pumps are running.
• When the pumps stop, the pressure should level off to about 137.8 –171.2 kPa (20
– 25 psi) and hold.
• If the pressure drops below 137.8 kPa (20 psi) quickly, it is an indication of a fuel
leak.
If a fuel leak is suspected, proceed as follows:
• Remove the fuel rail retainer nuts.
• Remove the water outlet hose (port rail only).
• Slide the rails away from the cylinder heads [keeping the direct injectors in place
in the cylinder heads].
• Turn the ignition key to the ON position to pressurize the system and look fuel
leaks at the injector openings.
• Replace any leaking injectors.

What color are your injectors? I have a few spare ones I may be able to sell you.
If this is all good, go into the vst & check the grommet on the h.p. pump outlet for splitting this will cause the pressure to bleed off quickly as well. as for it not starting , if everything else is good , dont hesitate to put a new set of high dollar plugs in it . even if they "appear" to be good! I have fixed plenty of opti's with plugs alone, after my diagnosis indicated all else good. dont sink it yet, there is hope!
 

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Discussion Starter #7
Pressure is good and holding better now since we cleaned the fuel regulator plugs are the 25 ea lol it was running for a min after cranking it over pressure up like its suppose to be but turned it off and and would not start again with good pressure
 

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Check again for fuel in the air side. you may have air injectors plugged up. But on another note, make sure your battery voltage is GOOD at the engine when cranking. Too many times a weak battery will crank the engine over and sound great, but there is not enough voltage to actually turn on the computer to run the engine while cranking.
 

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Discussion Starter #9
BINGO we have a winner lol you hit the nail on the head not only was the battery common ground between the two batters disconnected only allowing one (the smaller of the two) to feed the motor but the VHS radio has been on this whole time draining the battier as well. So a recap of events sea foam added ran let sit two weeks it cleaned the fuel system up. First time taking out after treatment slowed trash to trap under fuel pressure regulator and tracker valve. Also both high and low pressure pumps lost their out put. Replaced both with new charged battier motor runs fine now lesson learned
 

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Make sure your batteries are charged. The computer needs a min specific volatage....If the voltage is outside the voltage range, it can ruin the computer. This has been the Optimax achilles heel. They are quite expensive. Just be aware of battery maintenance and you can avoid a $1000.00 plus hit in the wallet.
 

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Discussion Starter #12
ok fuel problem fixed took boat out sat 17 miles with out a problem, then i get an alarm with the oil, after online research it can be oil level in the tank on the motor low or electric oil pump not working after calling a buddy turned key on shifted in and out of nutrual three times oil pump is runing and main tank is using oil and motor tank is staying full, motor limited to 4000 rpm??? after turning around heading back in at the 15 mile mark another alarm now its water or lack of, motor limited to idel only water pressure was good while running at 4000 rpm holding around 12.5 -13 PSI at idel still peeing good voltage 13.5 or so battiers fully charged. could I be having sensors going out at the same time of a comon wire to both? and final question where can get the program to install on my laptop to run all the checks and test? along with the wiring harness to plug in to the computer??
 

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You just put the engine back into break-in mode and will be using a lot more oil when you shifted it like you did. Typically on those the oil tank sensor or float magnet goes bad and will give the oil alarm. Just need to test it to see which one.
 

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Discussion Starter #14
I am hoping that is what it is on the oil side, as for the water I had good pressure while running and at idel it was peeing good to so I am not sure, either way I am changing the water pump servicing the lower unit and replacing the thermostats, something I should of done when I brought it home.
 

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could be the fuel or air regulator diaphram - that was my issue try the guy online at the pelican services he did mine runs great now!
 
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