Need help, strange problem with ´04 z300 hpdi engines

[drakserrato1]

Here I ask for help!, I have 2 z300 turc hpdi engines (left and right) they start and seconds later die, we changed fuel pumps they are reading 50 psi but mechanic scanned the engines with yamaha diagnostic system and it shows 1,560 psi on the high pressure pumps instead of 1,015psi, and it reads exactly the same on both engines, Ive been looking for issues like this on forums but no one seems to have this problem ever, I am on a deadline to send this boat on an ecological research proyect, I´m in México but Yamaha doesn´t sell hpdi engines in México so they don´t give support for it and I´m desperate.

can the high pressure pump be regulated? or there might be something else causing this?
I would apreciate any help, thanx.

[pstephens46]

What is the condition of the batteries?

[drakserrato1]

Batteries are brand new and fully charged

[drakserrato1]

Do batteries have something to do with hpdi high pressure pump? I think they are mechanical

[Masonmobilemarine]

If both engines are acting the same exact way I would ignore the engines and look at what is going to both of them.

Fuel, battery, key switch. Can probably rule out key switch.

I'd double and triple check battery, and then check fuel.

Do you have 1 water/fuel separator supplying fuel to both engines or do you have 2 separators (one for each motor)?

Is this boat new to you? Was it running fine before? Did you do any work recently?

[drakserrato1]

Batteries checked both of them
fuel lines 3/8 brand new
1 new Walter/fuel separator for each motor (2 separators)
It was running but then stored for almost 8 months

[pstephens46]

Do batteries have something to do with hpdi high pressure pump? I think they are mechanical

The pump in the VST is electric. Trying to identify something common to both motors. 8 months of storage may point to a fuel issue. I’m no expert on the HPDI but I do know they like clean fuel.

[99yam40]

Hopefully Rodbolt17 will see your post and be able to help.
not many of those HPDIs around and running now a days

Hard to believe both motors would have the exact same problem at the same time.

I have no idea what the proper PSI is for that motor.
there has to be a pressure regulator

[drakserrato1]

Nothing yet, I can´t find anyone that knows what´s happening with my engines

[rodbolt17]

HPDI has tweaked many a mokanik.
it is actually fairly simple.
at key on the main relay gets energized and powers up various components that the ECU controls the ground path of.
has any one of them been checked?
at key on the medium pressure pump runs 3-5 seconds,do they?
if high pressure is out of spec it will be high lighted in red on the diagnoses screen,is it highlighted?
the system uses a TCI ign system that requires 12v,does it have it?
the injection system uses 12v and is stepped up by twin drivers to about 90V,is it there?
can you keep it running by misting fuel directly into the throttle plates?
the only way it dies is if you lose spark or fuel.

[pstephens46]

HPDI has tweaked many a mokanik.
it is actually fairly simple.
at key on the main relay gets energized and powers up various components that the ECU controls the ground path of.
has any one of them been checked?
at key on the medium pressure pump runs 3-5 seconds,do they?
if high pressure is out of spec it will be high lighted in red on the diagnoses screen,is it highlighted?
the system uses a TCI ign system that requires 12v,does it have it?
the injection system uses 12v and is stepped up by twin drivers to about 90V,is it there?
can you keep it running by misting fuel directly into the throttle plates?
the only way it dies is if you lose spark or fuel.

Got another HPDI thread going here that also could use your attention.....

[drakserrato1]

HPDI has tweaked many a mokanik.
it is actually fairly simple.
at key on the main relay gets energized and powers up various components that the ECU controls the ground path of.
has any one of them been checked?
at key on the medium pressure pump runs 3-5 seconds,do they?
if high pressure is out of spec it will be high lighted in red on the diagnoses screen,is it highlighted?
the system uses a TCI ign system that requires 12v,does it have it?
the injection system uses 12v and is stepped up by twin drivers to about 90V,is it there?
can you keep it running by misting fuel directly into the throttle plates?
the only way it dies is if you lose spark or fuel.

HI, now continuing with the proyect
I´ll make the grounds be checked.
at key the electrical pump works fine (5 seconds and stop) (50 psi)
at the yamaha diagnosys sitem apears in red and reading 1,670 PSI (wich is way too much)
we have 2 batteries brand new and fully charged 12v.
and we are going to try running them by misting in the throttle bodies, thanks.