03 Yamaha HPDI 175 Cutting Out

[skeeter175HPDI]

Hey, Hows its going with everyone? Not to good here, I just bought a 2003 Yamaha HPDI 175, and It is still at the dealer because of this 'cutting out" problem. Right now, the dealer has put in a water separator and cleaned the injectors, and its worse now. The boat will not even come close to planing out, once the motor hits 3500 RPM, it will 100% shut down or just cut out and fall on its nose. They say they have called Yamaha, and Yamaha has said this is the first time they hear about it. I have read and found that there are a lot of people on here that has had or still has the same problem. Would anyone know what is going on here? Any ideas of to what is causing this? I have a dealer doing all the work so anything I can ask them or tell them would be to great help. The fuel is from the same gas station, and is just unleaded fuel. Let me know if anyone can help me!

Thanks for reading and/or helping!

Alex

[99yam40]

there are multiple screens/filters in that fuel system that need cleaning/replacement on a regular basis.
Monitoring the high and medium fuel pressures while the problem happens will tell you where the problem is if it is a fuel related problem. I have read that when the pressure drops too far the motor will turn off like you turned off the key. a good Yamaha tech should know this stuff

[skeeter175HPDI]

Alright.....This motor only does it when there is a load in it. It will not do it while in the shop hooked up to the hose. Only when we are on the water trying to push to the boat. Why would that be? Also I have seen the word VST filter? What is this?

Thanks for the help so far!

Alex

[99yam40]

Motors do not need much HP or fuel to run with no load. they should be checking it with a test prop or on a dyno to load it up at the problem RPM. Or at least on the water loaded up like normal.

A Yamaha service manual would be a very good thing for you to buy and read up on to see what all you have on your motor. If not just search the different forums and read up on what you can find on HPDI

[skeeter175HPDI]

Are these motors as good as I hear a lot of people say they are? They sure should like a lot of trouble?

[skeeter175HPDI]

What is a test prop?