Engine shuts down at WOT

[Lineman111193]

I have a 1996 200 Mariner EFI. Yesterday at blast off from tournament, I was at WOT when suddenly without warning the engine just shut down. I immediately put motor in neutral and it fired right back up and we took off again with no problems. We went about six miles at WOT and it shut down again. Same thing again, fired up with no problems. When it dies there is no warning like fuel starvation (sputtering, coughing, hick-ups, etc....) it's like someone turned the key off. On the way back to weigh in I ran motor at about 5500 rpms with no problems. With this symptom I would suspect it would be the RPM limiting module but the manual says that it only shuts down half the cylinders and engine will still be running with the alarm going off. Well there is no alarm (my alarm works) and it kills the whole motor not just 3 cylinders.

- Oil injection was taken off 2yrs ago. Premix 50/1
- Rebuilt fuel pump that is mounted on block 2 months ago
- All new fuel filters (fuel separator and small filter that is for recirculating)
- I have a temp guage mounted on dash. Never was hot when engine died.
- Fuel bulb stays hard
- New impeller (lower base and upper base replaced 2 months ago)

In other words I P.M. my boat regularly. This problem has me stumped and any knowledge pertaining to this problem would be greatly appreciated.

 

[Randy R]

Re: Engine shuts down at WOT

Check and make sure the fuel tank breather is is working. Also make sure you don't have anything floating in your tank that could be sucked down and pluging the suction line under full throttle. You might trying hocking up a tempary tank and new fuel line and take it for a test.

 

[Faztbullet]

Re: Engine shuts down at WOT

Sounds like the high pressure pump in VST tank is failing or ECU fuel pump driver board is going bad. take a test light out with you, when it quits ,leave key on and see if fuel pump is running. If not take light and check for voltage at pump. If no run and voltage=bad fuel pump. if no run and no voltage= bad driver board. Send to Shawn @ Rapair/CDI for repair.

 

[Lineman111193]

Re: Engine shuts down at WOT

Hey Fatzbullet. Thanks for the input, I will try this weekend testing with test light. Either way, it is going to be expensive to fix but if your gonna play, you gotta pay. I replaced electric fuel pump myself 5 yrs ago so maybe it won't be that but I here the ECU's ain't cheap either. Post later what I find out. Thanks again.

 

[Faztbullet]

Re: Engine shuts down at WOT

When ya get it tested and if it is a ECU problem call Shawn and see if he can give ya a guestamate on repair. If its to expensive pm me and will give ya racers fix for ECU driver failure.