04, 150 HPDI servicing questions for tech.

[dan_k]

Hi, I have a 2004 HPDI 150hp

I bled the oil pump as in the service manual and disconnected the feed hose and oil should FLOW. Now I would not call it flowing more like intermittent weeping is this normal? It would seem to me as being enough oil for the amount that HPDI?s use. The oil out of the bleed screw I would call flowing. Yamaha give all these nice precise measurements for everything else but a vague flow for this procedure.

Also, the first filter on the motor; after priming to the top of the cup it seems to level out just above the bottom of the filter element when running. Changed all my fuel lines and didn?t notice this before if it is normal.

Final question, when priming VST you do use the primer bulb, correct? My concern with this is about the oil being injected in the tank as well. How does oil get injected if you use the primer bulb for filling VST after being emptied?
thank you for any help,

 

[dan_k]

found old post on vst tank priming

found old post on vst tank priming

I did find this post on priming the VST for a '98 Yamaha 250hp Ox66:http://forums.iboats.com/showthread.php?t=142580&highlight=priming+vst
I do not feel comfortable running that fuel in the tank without some mix ratio 50:1 which seems easy enough with another remote tank. worst case i clean O2 and plugs right? let me know how long it should take to burn the fuel in the VST at idle?
thank you for any help,

 

[dan_k]

Re: 04, 150 HPDI servicing questions for tech.

For others that may look at this post, you do not need to primer the VST with premix on HPDI's. The HPDI's do not mix the oil with fuel at all. look at the link below from yamaha: http://www.yamaha-motor.com/outboard/feat_hpdi_2006.aspx
Better to ask a stupid question than make a really stupid mistake.
thank you no one for any post yet,

 

[rodbolt]

Re: 04, 150 HPDI servicing questions for tech.

dude be patient
yes I am a Yamaha master tech however I do still work daily for a living as well as still trying to have fun so I am not always online.
there is an oil output test and yes oil doesnt really flow but rather pulses.
yes you refill(prime) the VST with the fuel primer bulb. hence the name primer bulb.
DO NOT premix HPDI.
the VST at speeds above 1800 RPM or so has about a 1500/1 oil mix supplied by the inline electric pump to aide in injector lubrication.
dont forget,lift pump life is about 3 years and the inline medium pressure filter needs annual replacement as well as VST filter cleaning.
yes the filter cup wont stay full as its on the suction side of the system.
but any questions you have I will attempt to answer.
but now I am off to take the honey to a decent seafood dinner

 

[dan_k]

Re: 04, 150 HPDI servicing questions for tech.

Hi Rodbolt,
My apologies Rodbolt, I was getting jealous seeing everyone else?s post getting replies but mine and wanted some of the info before going out of town. Thank you for your help so far and hope you got lucky on your dinner date or all went well at least.
I do have some questions about the YDS; the electric oil pump shows low in neutral I was able to get to go high bring the boat up on plane. This is in relation to flow I assume from the remote tank correct? Also is this an oil flow sensor or just a step up in voltage to the pump?
Other question about the software, I monitored the low fuel pressure pumps as I had my friend punch it to about 4k and saw it go just a little pass the max and only for a second and never highlighted it self in red. This should drop a little once I change and clean the vst and high pressure filter I would assume. What are your thoughts on the pump being able to go over by .4 more and only for a second or so?

Dan K.

 

[rodbolt]

Re: 04, 150 HPDI servicing questions for tech.

dude, go re-read the instructions.
the electric oil pump for the VST is all that is monitored by the YDS software.
above 1500 its on and below its off.
that simple.
low pressure fuel is NOT monitored,period.
medium pressure fuel is NOT monitored,period.
High pressure fuel is monitored and should remain in the 700 PSI range at all RPM's.
the engine electric oil pump has NO relationship to the engine oiling system.
its sole function is to deliver a moderate,fifteen hundred to one,1500/1, oil to fuel ratio to aide in lubricating the high pressure fuel pump and injectors and that is all.
the engine oiling pump is a variable ratio mechanically driven pump.
the transfer is controled by sw1,sw2 and swB, B is in the remote tank.
best I recall the range on the high pressure fuel is about 200 PSI, but without looking I cant remember.
when you change the medium pressure inline filter its IMPERATIVE you use the correct clamp on reassembly, no worm type hose clamps.