2008 Optimax 115 Turns Over wont Start

[ChrisPage227]

Serial number of the motor is 1B498653. I bought it rebuilt at the beginning of this year. I have put a little over 6 hours on it according to the SmartCraft gauge and for the most part everything has been smooth sailing. The water pressure has only be about 8PSI when on plane but the engine temp has been fine, 140 when idling through the no wake zones, down to around 100 when running. But I took it out the other day and it wouldn't start. Turned over but wouldn't start. I noticed that I was virtually out of gas so I brought it home after trolling around for a while. Too it out again with a full tank of gas and fully charged battery, still wouldn't start. Turns over wont start.

I checked the kill switch and flipped it open and shut a few times. I have a primer bulb on the fuel line and that is pressuring up. I had disconnected the fuel line from where it goes into the fuel pump/filter and it was still pressurized from the bulb. Plenty of gas and pressure. The night before I had my issue starting I had replaced the fuse panel under the dash of the boat. Which is fed from a fused hot off the battery but just has the bilge pump, fish finder, livewell pump, etc. running through it. After I was done installing it I was checking everything and when I hit the airhorn button it fried the horn fuse. I put anther fuse in the see if it would happen again and it did. Seems like the horn has failed and is shorted. Fair enough. But this happened the night before I could no longer start. I am wondering if somehow I might have damaged the motor from this? Or possibly disturbed the kill switch wiring when I was under there? I doubt the latter but I suppose I don't know.

I have read that the master power relay is a common failure so I suppose I can check that. I do get the warning horn beep when I put the key in the on position and I can hear the fuel pump prime up when I put the key in the on position. And when it is trying to start I do hear a few pop pops like it is about to fire and it creates a small amount of smoke out the exhaust. But I am only comfortable cranking it for a few seconds at a time.

Would the master relay not power the fuel pump if it was failed? Meaning if I can hear the fuel pump prime up when the key is in the on position does that rule out the possibility of the relay being bad? Or am I headed down the wrong path here?

[JOE54]

need to test air and fuel psi possible split grommet on top of high psi fuel pump known problem

[SilverFox579]

There are fuses on the engine (Joe54 would need to tell you where on the 1.5L) and suspect it's possible you may have shorted some dash wiring and blown a fuse under the engine cowl.

There are no specs for on plane water pressure only idle and WOT. You should have 1 - 3psi at idle and 12+ WOT.

[ChrisPage227]

When I went to check pressure on the two schrader valves on the fuel rail I got fuel out of both. Which lead me to a torn tracker valve diaphragm. I can get the part, but do I need to have the rail/injectors recalibrated?

**edit** fuel pressure diaphragm not tracker valve. Don reminded me that my engine doesn't have a tracker valve ;-)

[JOE54]

install diaphragm only have pressures tested

[EuropeanAM]

Also keep in mind that diaphragms are not the only thing that can cause fuel on the air side of the system. ANY AIR LEAK can also cause it.