2009 90hp optimax fuel issues

[Donniec2000]

Hello.
I'm writing in regards to a 2009 90 hp optimax motor serial # 1B751611.

Motor has ran great until now. Motor was starting but instant dies.

I ordered and replaced fuel filter. Vst and filter were filled with orange crystals of some sort of gunk. The boost pump and high pressure pump areas were clean and free of any debris.

The pump on the side of VST i pulled apart and was full of the orange crystals. I cleaned this out and the valve on top and reassembled.

Put everything back the same way it came out.

Tried to start engine and will not start at all now even for an instant.

Fuel pressure on side of VST is 0. Fuel pressure builds at the fuel rail to around 50 very slowly.

I did replace the fuel line and primer bulb. Tested for spark and am getting a consistent spark, but it is red.

The small rubber piece (bushing maybe?) On top of the high pressure pump has a small tear and is misshapen, so I'm ordering a new one.

Any advice on where to go next? Should i rebuild the pump on side of VST?

Starting battery is brand new, 1000 mca.
New fuel line and primer bulb.
New fuel filter.
Can hear a fuel pump run when key is turned for around 3 seconds.

Thank you for your time.
Donnie

[SilverFox579]

Welcome to BBC!

There is an excellent FAQ at the top of the 2.5 & 3L forums with tons of Optimax information, much of which, applies to all regardless of displacement.

Here's the topic you need to read, then follow, every single step in order without skipping anything - FUEL LINES AND PERFORMANCE PROBLEMS

[Donniec2000]

Thank you! I didn't go into the other forum to browse. Definitely going to check it out and hopefully get this vopti fired up !!

[EuropeanAM]

Need to make sure:

1. Primer bulb will pump up firm and is filling BOTH the front (filter) chamber AS WELL AS the rear (Pump) chamber of the VST.

2. REPLACE the outlet seal for the HP fuel pump. DO NOT ATTEMPT TO START AGAIN. If you have ZERO psi at the back chamber, you have either NO FUEL in the aft chamber, or no power to the pumps.

[Donniec2000]

Update.
Parts came in today for mechanical fuel pump rebuild and the outlet seal for high pressure pump.

Rebuilt the pump, replaced seal, checked for leaks, then went to check fuel pressure.

I don't think my fuel gauge is working right as it didn't get above 10 psi at VST and 20 psi at fuel rail. When pressing shraeder valve, fuel rocketed out of both.

I went ahead and attempted to start the boat. After a few second of cranking, it fired up. I ran it on the muffs for a minute of idling and it sounded good. That's when i noticed no water coming out of the pee hole. Time for a new impeller now i guess. It's always something!

Thank you for the help and time you took!
Here's to fishing!

[SilverFox579]

Check the telltale hose for obstructions, i.e. dirt daubers, mud wasps, etc.

If your water pump is more than 365 days old or has more than 100hrs on it since last replaced, it's overdue. Check those FAQs for recommended service intervals most all of which apply to the 1.5L as well.

[EuropeanAM]

Normally you will take Air and Fuel pressure tests with the engine RUNNING (fuel pressure is equal to AIR pressure + 15 psi on this model).

So if the engine isn't running, you'll only see about an average of 15 psi (may show 20 when pump is running, and drop to 10-15 when pump shuts off).

Change out that impeller and the gaskets... and see where you're at.

[Donniec2000]

I changed the impeller, gaskets, and greased up everything that needed it. Motor fired up purring and water properly cycled through and out the hole. I had tried running weed eater line thru the hose as it had clogged up before. New impeller did the job.

Crappie fishing Monday and testing out the motor for longer than a few minutes on the muffs! Thank you all again! Happy Easter!

[SilverFox579]

Good to hear. Happy Easter to you as well!

[Donniec2000]

Just a quick report back. Had boat out several times this week and motor purred like a kitten. Starts easy, idles, runs great. Thanks again!

[JOE54]