HPDI Water in Fuel

[NAESB811]

I have a twin 200HP Yamaha HPDI (Z200TRLY) - year 2000.

I went out yesterday, everything running fine. An icon on my Fuel Management started to flash. I looked it up and it said it was a water in fuel alarm. I spun off the external fuel water separators, emptied them into glass, It looked like all fuel. I checked the internal separators, the floats were in the low position. I put the fuel water separators back on, pumped them full and turned the keys on. Alarm was gone.

I ran home slow (3 miles or so). as I got in the harbor, the alarm started blinking again. I docked, pulled the internal separators, emptied into a glass jar, appeared to be all fuel, smelled like gas. I reinstalled, filled them up, the floats stayed low. Key turn on the port, 3 beeps. Key turn on the starboard, continuous beeping. Water in fuel alarm is still on. I unplugged both of the sensors, water in fuel alarm is still on.

Both engines appear to be running fine. I didn't push them but no studded or hesitation as for as I could tell.

I am going to have a Yamaha Mechanic come up this week and look at it. Anything else I can check while I wait for him?

EDIT: both engines run off the same tank. There is no audible alarm, just the flashing on the gauge

Thanks for you input. These motors are great when they are running right, would like to keep them going for a few more years.

yahama water in fuel - Imgur

[99yam40]

if no water in cups and floats were down then it must be a bad water in fuel switch

[NAESB811]

if I unplug them, do I have to Jumper the connection to make the alarm shut off?

I would like to confirm which engine the faulty switch is on. Is so, i assume I can do a continuity test on the switches to verify which on it not working

[99yam40]

Since there is no audible alarm going off with the flashing icon, you need to wait for someone that knows that system to see what they have to say

[boscoe99]

Does you external fuel filter have a wire coming from the bottom of it? If so, that wire can be connected to the FMM. If and when the filter gets water in it the water in fuel caution icon on the FMM will flash. There will be no warning.

If the filter does not have water in it then the sensor might have failed. Disconnecting the connector at the bottom of the filter should cause the icon to stop flashing.

If the primary fuel filter cup was connected to the FMM, and if that filter had water in it (or a failed sensor), then the warning horn would sound and the motor would go into RPM reduction mode.

I would suspect that you have a Z200TXRY and an LZ200TXRY model. Please confirm.

[boscoe99]

After all else fails read the instructions.

[NAESB811]

i think Z200TXRY and an LZ200TXRY is correct. I will double check the shaft length but 25' sounds right. A counter rotating pair of year 2000 - 200HP HPDIs on a 1999 247 cc Edgewater.

There are no wires on the external filter. There are wires on the internal filter tanks. I unplugged both filters, alarm still was flashing. There is no beeping with the flashing. There was beeping with when the key was turned but it stopped when the motor was started.

Thanks for the help.

yahama fuel separatorÂ* - Album on Imgur

[NAESB811]

I went out last night. Keys in, 3 beeps on both, alarm was flashing. Started the motors, got to the dock, buy the time I was there the alarm was off. I found one plug that looked fouled but that was about it. Replaced both external water separators, the gas was clean, no water or cloudiness. Must have just been a bad sensor read. I ordered an spare in case it happens again.

[99yam40]

I went out last night. Keys in, 3 beeps on both, alarm was flashing. Started the motors, got to the dock, buy the time I was there the alarm was off. I found one plug that looked fouled but that was about it. Replaced both external water separators, the gas was clean, no water or cloudiness. Must have just been a bad sensor read. I ordered an spare in case it happens again.

Help me understand this.
you put both keys into the ignitions, both beeped 3 times and caused the water in fuel alarm to flash when you turned the individual keys to the on position, correct?
Did the indicator stop flashing when the 3 beeps stopped?

Not sure how you started the motors before you got to the dock and not sure how long it took for the alarms to go away or for you to get to the dock from where ever you were

[NAESB811]

when I put the key in I got the standard 3 beeps on each motor when turned to the on position.

Fuel management gauge powered up ( i believe with the port) , the alarm icon was flashing in the lower left corner. I checked the floats in the internal water separator, neither were floating.

I started the motors, sounded fine. It took about 30 seconds to get to the dock off the mooring. The water in fuel alarm icon shut off by the time I got there.

[99yam40]

thanks for the clarification.
i am sure the beeps are not due to the water in fuel light being lit up/flashing.

probably just a test of the alarm at key on and indicator of one motor off with key on.

may be best to hook the motors to computer to see what they are indicating/seeing. But motor ECU may not be seeing it if not beeping, just gauge is seeing something

Not sure if it closes or opens switch to indicate water in cup.. bad connection, wire, or switch would be my thought with the little knowledge of the system I have.

hope someone else can give you more info

[rodbolt17]

look in the bilge.
look for the FMM harness.
carefully inspect the white/red lead at the bullet connector for corrosion.
if that lead gets in the water it can set a false alarm.

[NAESB811]

thanks, I will check that out next.