Need Help with 200HPDI stalling after 3 - 10 seconds

[Larry1200]

I give up. I have a 2007 200HP Yamaha HPDI that I have been troubleshooting for a while. The motor will crank right over and run for about 3 – 10 seconds then shuts down. A little history on this motor: I bought this boat used. The motor only has 28 hours on it. It sat for 8 years with bad fuel in the tank and fuel system. I am sure that the previous owner left old fuel (ethanol) in the tank for this entire time and had tried running bad fuel through this motor since it was new. The fuel system was a wreck and had to be completely cleaned and components replaced. I had the motor running in the yard after my initial cleaning and repairs, but when I went to launch it the problem with the shutting down started. For the few seconds it runs it sounds great, then just shuts down on it’s own. Now for what I have done so far.
1- Cleaned the entire fuel system.
2- Cleaned and flushed fuel tank and installed new fuel lines and pickup, filled with non-ethanol fuel.
3- Replaced all filters
4- Replaced the Electric fuel pump.
5- Replaced the 2 diaphragm pumps
6- Had the High Pressure fuel pump disassembled and cleaned and all (Mystery ) filters replaced
7- Fuel rails and injectors cleaned
8- Swapped O2 sensor, HP Fuel Sensor with known good.
9- Adjusted the TPS and swapped it with good.
10- Tried new ECU
11- Tried new Injector modules
12- Checked gap on the Crank Position Sensor
13- Fogged the engine with Evinrude Engine Tuner
14- Swapped out ignition switch.
15- Swapped kill switch.
16- Tried auxiliary fuel tank.
17- Hooked up Diagnostic computer and no error codes.
18- Cleaned VST, float and needle valve, pressure control valve.

I am out of ideas. Can anyone help?

[99yam40]

these are things that you did to get it to run originally.
What have you done now that it has the new problem ?

monitor fuel pressures and spark

hopefully Rodbolt or Boscoe will chime in on what changes happen after a few seconds at start up.

I beieve some cylinders shut down, so if some of the others are not firing properly the motor stops.

could be you have injectors or screens plugged up again

[Larry1200]

I initially got it running. It was running fine on the trailer in the yard. When I went to lauch it for the first time it fired right up and ran fine for about 20 min. When we went to take it for a run it stalled and started doing this stalling. I have went through the fuel system again and checked everyting, all filters pumps and even removed the High Pressure fuel pump and had it service and the fuel rails and injectors cleaned after it started.

[99yam40]

Anything show up new on computer system?

are fuel pressures dropping(high and/or low)

Is spark going away?

[Larry1200]

No error codes or issures are showing up on the YDS computer. I havn't checked since I had the High Pressure fuel pump and injectors cleaned. But the pressure was getting up to 1200 psi, according to the YDS, before I had the High Pressure fuel pump and injectors cleaned. Havn't checked it since. I am waiting for the mechanic to bring the YDS back over to check again.

[Larry1200]

I checked the pressrue on the output of the VST yesterday and it was at 50 psi when the motor is started.

[Larry1200]

I have checked all the fuses and relays on the motor. As well as the oil pump in the reserve tank. But I will check again. Thanks

[99yam40]

I checked the pressrue on the output of the VST yesterday and it was at 50 psi when the motor is started.

It is good to see what the pressures are when it is started and running, but need to monitor pressures when the problem shows up to see if they get out of wack

[Larry1200]

VST pressure seems to be holding. Starts at 50 psi during start and backs off a little. I need to get the computer hooked back up to see what the High Pressure pump is doing now that I had it cleaned and the injectors cleaned.

[99yam40]

get the tech to hook it up and monitor everything while it stalls.

Something is changing.
I believe the motor should idle even with low pressure, but not carry any load.
If it cannot even idle it may be running out of fuel completely or ECU is shutting down too many Cylinders.
Have you checked to see if it will idle in gear or in neutral

[Larry1200]

It will not idle in neutral or in gear and I even swapped out the ECU and injector modules. It has to be something simple like the run circuit is shorted to ground, but I can't find any open or shorted wiring. I need to check the wiring harness from the key switch to the motor next. Everything is like brand new.

I know there is a microswitch at the shift linkage and that is working correctly. Is there one in the shift leaver?

[rodbolt17]

try a set of plugs.
when cranking all 6 spark.
once running 2 cyl quit.
if you have some fouled plugs once running it can stall if some plugs are fouled.

[Larry1200]

Thanks I will check the plugs. I did replace them, but since I have been trying to start it they may have fouled up.

[Larry1200]

Checked the Plugs. They look like new. Still no solution. I rang out the wiring harness to the key switch and got good continuity on on the wires.

[Challenger215]

Bump for this guy.
Real curious to see what this turns out to be.


200HP HPDI Stalls within seconds of starting. Need advice - The Hull Truth - Boating and Fishing Forum