Help identifying mystery part for Yamaha fuel management system (1999 225 OX 66)

wfeagley

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I'm installing a Yamaha Fuel management system on my 1999 228 Seafarer with a 225 OX66. The instructions that came with the fuel flow kit (6Y5-W0088-55-0) and the original rigging guide show an optional part that sits between the fuel tank and fuel flow sensor. The wiring harness that came with the kit has two leads to connect to this mystery device. The kit instructions have a note that says, "If the fuel line is used for a kicker supply, be sure to install a valve in line or sensor ventilation could occur."

This mystery part is obviously some sort of check valve / anti-siphon device. I do plan to install a kicker so I want to get this setup right now. Does anyone have a part number for this mystery part?

1997 yamaha rigging OX66.png
 

glacierbaze

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ABYS wiring protocol w/r(white with red stripe) indicates several fuel related uses, alarm, indicator, pulser.
I seem to recall pulse dampeners being required in some installations, years ago when I was using Floscan sensors, and that was the first thing that popped into my mind. I don’t think a check valve/anti-siphon valve would be wired. Your diagram is showing a portable tank, but if that was replaced by a large inboard tank, with an electric fuel pump, a pulse dampener might come into play.
 
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Parthery

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The pic references 6Y5-85752-02-00 which is the fuel flow sensor which goes in-line. If you are planning to run a separate line to the kicker motor, I'm guessing you will tap in off the 2nd output in the fuel filter assembly, which should render no need for the check valve.

The fuel management kit from Yamaha is ridiculously pricey. If you have a GPS that can take N2K inputs, you can get the same info for about 1/2 the cost. Both SIMRAD and Garmin make fuel flow sensors that connect to a N2K backbone and show the info on your GPS. I did that with my 225 OX66 and it worked perfectly.
 

wfeagley

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Glacierbaze, Thanks for the ABYS wire reference and the pulser reference. That make a lot of sense to me. I read some threads last night on THT and see that the fuel pumps on the OX66 are always running so I should not have any issues with inconsistent fuel flow.

Parthey, I'm already committed to the Yamaha system and made a new dash to install the fuel management gauge. I also use an old Raymarine GPS/Radar/Fish finder system that I finally have working reliably and really don't want to introduce anything new to it. Thanks for the tip on tapping off the filter. Hopefully mine has one. The original rigger mounted it so I can't see that side of the housing at the moment, but I need to un-mount it to get my fuel flow sensor connected, so I'll find out soon enough.

All that said, if anyone knows what that "opt" item is, please let me know.