Yamaha 200hp hpdi

[Fightin Irish]

HAS ANYONE EVER HAD A PROBLEM LIKE THIS?when i am  cruseing for about an hour my one motors rpm start to drop and if i prime the gas bulb it starts to run fine again for a while.also happens waiting for the bridges in shark river inlet.Yes they are new primer bulbs this year and i have changed fuel/water seperators a few times this year already.Does anyone ever encounter this?the motor is a 2001 with 450hrs on it.any help or ideas will be helpful I think it could be a high pressure fuel pump but i am not sure,

[Still Running]

Sounds like it running out of fuel for some reason. Can you switch the fuel lines on the motors so that the port engine is using the starboard fuel line? If the problem stays with the same engine, then the problem is in the engine and not the fuel supply.
Then you can check the fuel system on the engine or the line back to the tank if the problem moved to the other engine.
You said you changed fuel/water separator, but what about the filter on the engine?

[CapBob]

Check the diaphrams in the fuel pumps.....had that problem twice over the last two years.


Engine sputters to a stop at high RPM, floods itself out.......Pump bulb will not stay primed.

Open engine cover and pump primer bulb see if it is leaking out of fuel pump.

If you replace one, replace them all, Yamaha changed the diaphrams because of the ethanol