# 2000 200HP HPDI fuel flow sender location and part



## philthefish (Aug 10, 2009)

Hi folks,

I've got a pair of HDPI's that thanks to lots of help from here and around the web, I got running like tops now for 3 years. (Turned out to be VST corrosion for those of you who have 'em...)

In any case, recently the port side engine fuel flow meter (yamaha digital) started fluctuating wildly, by 3-5 GPH. Both of these have been rock solid for the duration and both engines are running smoothly - or so they sound in any case.

I'm given to suspect a faulty sender in this case - or corroded contacts. I'm going to look into that before I start actually diagnosing fuel pressure, swapping the dreaded strainer, or other things. There's just one problem...

I can't find the damn thing! I've looked at every yamaha schematic, googled my arse off, yet still can't find the location, much less the part number for the sender. 

Anyone have any clues as to where I can find this, or on which schematic? On the other motors, like the 2003 Z200, it's in the "Meter" diagram, part number 6Y5-85752-01. But this sucka doesn't exist on the 2000!

Thanks much.

Phil from Team Reel Unnecessary.


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## DOUBLE "D" & LV (Oct 2, 2007)

They will be near the fuel water separators in the boat if you have them. If you do not, they will be in the fuel lines somewhere that whoever rigged the unit placed them. There is no set place for the senders to go, so you will have to look for them inline with the fuel hoses (usually placed below deck somewhere). Sometimes, they will be installed on the fuel water separator housings. Hope this helps. Find a picture of them so you know what you are looking for.


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## philthefish (Aug 10, 2009)

Thanks D, I'll poke around down by the separators. 

These engines and digital displays were installed by the factory - Grady White. It's a 265 express. Most things on the boat are right where they should be, so I'll start there.

Do you know what these early Yamaha senders looked like? I can't even find the part number to know what I'm looking for... I'm guessing they can't look that different than the one's on the '03s.


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## DOUBLE "D" & LV (Oct 2, 2007)

They look the same. Only difference may be 3 screws on the body instead of four. They changed them from 3 to 4, but cannot remember what year they did that. Most of the old ones were updated during the warranty period. However, they look the same for the most part. This is what to look for.


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## philthefish (Aug 10, 2009)

Outstanding D, yeah those look nearly identical to the later ones. I'll let you know what I find out when I get down there tomorrow.

Many thanks. Let's hope it's a corroded contact...


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## philthefish (Aug 10, 2009)

Ok, well I got around to taking a look. Indeed they are the 3 screw sender types and they were just underneath the rigging for the water separators and fuel tank switch on each side.

The contacts looked fine, unit felt fine, minus some corrosion. I reseated the contacts and went to look up at the rigging in the dash. I was hoping I might be able to swap the fuel sender inputs up there to see if it's a faulty gauge or a bad sender.

Any idea what the failure mode of these yamaha sensors is?


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## DOUBLE "D" & LV (Oct 2, 2007)

Usually they stick and do not read. Could have bad sensors and need to replace them. Also may not be the sensor, could have an issue with the fuel system on the boat causing the flow flucuation like a bad fuel pump.


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## philthefish (Aug 10, 2009)

Hey DD. Hmmm... Yeah, I thought it might be fuel flow, but same symptom from both tanks. (My boat has twin tanks and twin engines). Checked the fuel system and did yearly filter service and she's running like a top, so I'm inclined to think it's the sender or contacts.

DD, it looked to me that the inputs from the sender are connecting to the RPM gauge, which then in turn is wired to the Flow gauge. There did not seem to be an obvious way how to switch the inputs from starboard to port. Am I correct in seeing that correctly, that the sender inputs go to the harness on the RPM gauge? I could not find those colors anywhere else...

You wouldn't happen to have a PDF of the rigging guide would ya? That would help a lot.

Thanks as always.


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## DOUBLE "D" & LV (Oct 2, 2007)

The flow sensors themselves are plugged into the fm gauge. The rest of the wiring is to turn on the unit and use the synch function on the gauge. In the first post you said it was only the port engine fluctuating. Is it now both, or did you swap the senders? Is this happening at idle only or is it at all rpm's? I will have to look for a schematic, but there is one plug to the fm gauge that the sending wires are in.


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## philthefish (Aug 10, 2009)

Good morning DD. 

I was not able to switch senders by the engines, as there was not enough wire to do so, and they were about 9' apart from each other. I could rig something if you think it's worth it.

My next step was to switch them up by the gauge, i.e. clip the connector and resplice, no big deal. However, the colors of the wires out of the senders do not correspond to colors going into the FM gauge, which threw me off. I checked it 5 or 6 times to be sure what I was seeing was correct. 

Instead of the schematic, do you have the wiring colors for the FM gauge connector? I'll switch em up right there and that should do it.

Lastly, I should ask what kind of beer you drink - because you're due a case of the good stuff.

Thanks.


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## philthefish (Aug 10, 2009)

*Purple and Purple/White are the senders*

Well, I finally found a diagram online after many hours of googling. Sheesh. I'd post it here but the forum has the woefully pathetic limit of 150KB for an attachment. 

In short, each side has Orange = hot, Black = ground. Purple = Starboard signal, Purple+White = Port signal. Orange and purple leads go to gauge, blacks appear to be grounded at connector. Each side seems to have it's own +12V Orange lead to the gauge, not sure why that is.

I'm sure can just swap the purple and purple+white with a splice and test it out.

Thanks again for the help out there.


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## DOUBLE "D" & LV (Oct 2, 2007)

I hadn't found any diagram in my books. The reason for the separate wiring is because each sensor has a power, ground, and reference voltage. It is like any other three wire sensor on an engine. The gauge has to independently check each sensor based on the power volts to the sensor compare to the reference volts from the sensor to calculate usage. Should be able to swap the wires to check, but be sure to seal them very well when all done back to original, or corrosion will set in..... then you will need a new wire harness. Have you tried just swapping the sending units so you do not compromise the wiring?


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## philthefish (Aug 10, 2009)

Swapping the sending units will be a big PITA. It's nearly impossible to get to them, and I'd rather not open the fuel lines unless I absolutely have to. Also, the senders are on opposite sides of the boat, so I can't just swap at the connector. Ugh. Nothing is ever easy right? 

However, I (crossed fingers) have a decent record with heat-shrinked, crimped connections on the boat so could probably make this work. Sounds like I had better swap the hot leads to. 

I have a feeling, because I have the 3-screw senders, that I'm going to end up removing the bad one. Makes me nervous...I have 200 HPDI's and you know how those suckers are about anything at all in the fuel system - keep 'em clean and they run like rabid animals.

Here's the schematic for reference. If you PM me your email, I'll send you the PDF.


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## DOUBLE "D" & LV (Oct 2, 2007)

Thanks.... just copied it to the computer..... email is in the signature also if you ever need it.


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