2000 175 HPDI

[Belle]

I have a 2000 HPDI, maybe 200 hours on the engine, which is on a backcountry flats boat. It may be the best engine I have ever owned and runs perfect except at 4000 rpm or above. It will run at the higher RPM for maybe 30 seconds and then cuts out...like its out of fuel. Slow down and the engine runs again, speed up and it cuts out. Does anyone have any suggestions.

Thanks...

[mudrunner]

Check your fuel/ water separator. Sounds like water in the fuel.

[Belle]

thank you very much for the reply...I have check for water many times...

[Ken]

Belle,
If you had water in the fuel, I believe your motor would be cutting out and running rough at all speeds.
Check your primer bulb when the motor cuts out - if it is collapsed, then there is a fuel restriction from there back to the fuel tank. If not, from there to the HPDI pump.
I believe your model Yamaha has two fuel pumps that feed the HPDI pump. Either one could be faulty and not delivering enough fuel at 4000 rpm and above.
The Yamaha shop manual has a procedure for testing the fuel pumps - you need one. Can order online at www.yamahapubs.com
Good luck [img]smile.gif[/img] ,
Ken K

[Belle]

Thank you very much, I will check the primer bulb, it is old. thanks again...Belle

[mudrunner]

Belle,
Ken's right on the money and beat me to the next thing to look at. Also make sure that the primer bulb is an OEM bulb and not an aftermarket one. The symptom you descrbe happened to a friend with a tempo bulb. Good luck.

[Ken]

mudrunner - nice to have you onboard [img]smile.gif[/img] ,
Ken K

[Belle]

Its very nice to have both of you on board...I will let you know what happines....I think it is a aftermarket bulb.......thanks again...Belle

[mudrunner]

Thank you both for the welcome. It's nice to have a place to learn some and share what I've learned through the years.

Carlos

[Belle]

HELP...HELP...Back again...checked for water in all the filters, two new fuel pumps, new primer bulb, checked the hose all the way to tank to assure there were no kinks, removed the ball and spring in the 90 degree turn going from the 3/8 fuel line into the gas tank, and as before the engine runs perfectly below 4,000 RPM...sneak up above 4 to 44 hundred and it appears to run out of gas....surges, sputters, and then slows down....and it never totally shuts off, idle for a second and again it will run perfectly for hours at a time until about 4000 rpm..then it repeats the above...any ideas...thanks Belle

[jb123]

i would try to isolate the issue by using a portable tank and fuel line, to rule out fuel supply.