ox 66 225 High Pressure Pump

[1 Finale]

So if the HP pump does not continue to run after starting and the engine stalls and the you restart it and it does the same. Then you take and run a ground from the neg side of the pump to the block and the pump runs like a top and will restart fine. What is the next thing to check.
Any thought's are greatly appreciated .

[99yam40]

the Ecu needs to see the motor running to keep the pump running , so You need to find out what the ecu needs to see to make it think the motor is running.
CPS maybe, but I have no real knowledge of this motor

[1 Finale]

Thanks 99, sounds like a **** of clue. Thinking of the pressure rectifier or pump relay. just have to know testing process. Let the ****s begin.

[1 Finale]

**** ****

**** ****s

[boscoe99]

**** ****

**** ****s

Exactly what I was thinking.

[1 Finale]

Was trying to type the word **** but starred me out .

[1 Finale]

ok emag backwards

[1 Finale]

and s,emag spelled it backwards. still no thoughts on my troubles.

[99yam40]

Thanks 99, sounds like a **** of clue. Thinking of the pressure rectifier or pump relay. just have to know testing process. Let the ****s begin.

Not sure what a pressure rectifier is,

But someone will come along that knows if the crank position sensor or maybe pulser coil signal is what tells ECU motor is running so it will keep the ground to fuel pump.
Seems it is getting a ground at start up but is not keeping it there once running, but that is just my thoughts and I know very little about that motor

[1 Finale]

Thanks 99, I believe you are in the ballpark. Hopefully there is a genius out there somewhere so I might be able to avoid the big Dealerships and them high dollar service centers. I have replaced LP fuel pumps cleaned HP pump screen new fuel line from tank to fuel/water sep. lower unit water pump and fluids. Just pulled the heads and cleaned water jackets and passages with new gaskets along with new thermos. *** what next.

[1 Finale]

Might be fuel pressure regulator and the fuel pressure relay.

[99yam40]

Posting your complete model # might get Rodbolt or boscoe to respond

[1 Finale]

2001 SX225TURZ OX66 FI

Late 2000 model

Thanks again 99

[rodbolt17]

only way to tell if its a pulser coil signal issue is hook it to YDS.

if the engine ECU does not get a running signal it quits.

it will run with the CPS disconnected.
it will run with any sensor disconnected.
if the pulser coil signal its looking for is not there it quits after the cranking signal is removed.
or a failure in the blue wire or resistor.

[1 Finale]

***, always heard if ya put the red wire to the green one it fires up. Don't have all them fancy Yamaha computer's to work with. Had this motor new with the boat going on 15yrs now. Kinda sucks to be putting to much money in it at this time in it's life.