How To: Recognize & replace a failing fuel pump FZ-07 MT-07 XSR Tenere

[Pursuvant]

Symptoms

A "ringing" tone loud enough to hear standing next to bike. Put your ear on the tank and there is also always a subtle "chirping" maybe 3 times a second that may be normal but seems to become louder over time/or stress of long hot summer day ride. Ringing rarely happens at first, several weeks between first three times it happened, then started getting a lot more often, 3 times a week. I was able to replace the pump before it failed, or before there was any actual fueling shortage symptom. Pump kept working, but it was screaming the failing ring. Just my symptoms, you could experience different symptoms.

Confirming

I pulled the bodywork off the tank and ran naked so I could get my ear down on the tank. With body panels around tank, its hard to be completely sure it's the pump. Other sounds resonate inside the tank. I ruled out other sources, the cooling fan, the ABS unit, the servo motor thing-ee between throttle bodies that provides idle air to fueling at idling speed. I pulled two of the three ABS sensors (leave the "controller" fuse and you will still have  a working speedo). And I waited for it to happen, with tools on bike to be able to unbolt the tank. When it happened again, abs is already disabled,  I let cooling fan  run thru an on/off cycle, while bike "ringing" and then during next fan on I unplugged fan power connector, had no effect on "ringing". Picked up rear of fuel tank and unplugged the harness connector while bike "ringing" - bingo, its the fuel pump.

Replace the pump

1 x 1WS-13907-10 fuel pump complete

2 x 1RC-24486-00 O-ring, fuel pump

I got two o-rings because I did not know if I would need to remove it a time or two while adjusting the "fuel level sender" that is part of the fuel pump assembly, to get the "full" and "reserve" sender levels adjusted. It came from the factory adjusted to kick in with the "reserve" signal when the 3.7 gal fuel tank gets down to 1 gal of fuel remaining. Having reserve kick in when 1 gallon remains seems excessive, but that is the same as the failing pump I removed. And if you are happy on the throttle, 1 gal doesn't get very far.

Installation

Boring, not much to note other than pay attention to the surface of the sealing ring area on the bottom of the tank. I did not do any "sanding" of that area when cleaning it up - I didn't want to scratch the surface because who wants to encourage a leak? I just wiped it with clean cloth and brake cleaner, that removed most of the discoloration of that sealing surface that is being attacked by the outside environment all it's life. Reused the round attachment bracket with four bolts, that holds the fuel pump and o-ring seal in the tank.

Can you replace just the fuel pump "tea bag" filter?

If you can find a source, the filter does have a simple "snap on" connector. But it's not sold in that way by Yamaha. It made no difference, because I had a failing pump, not a clogged filter. The filter was surprisingly clean, which probably means it lets dirt pass thru it all the time.

Pics tell the story. One interesting side note, strangers yell questions at stop light "what kind of bike is that?" when I ride with the naked fuel tank. I'm leaving it this way for a while, and be "beasty"

 

Failing pump on right, both pumps seem to have some adjustment ability to range & reserve trigger points

73K hard miles... wasn't a spark from a loose wire inside an oxygen tank on apollo 13 what blew the side off the command module?

there's a check valve in the assembly to keep the fuel from pouring out of tank when you disconnect the fuel line...

the filter is not clogged, at all, and that means it probably just passed dirt thru all the time.

And yes it would be easily replaceable, if Yamaha actually sold that individual part

[shinyribs]

Wow, those connectors got hot! Makes me wonder if the pump failing put extra load on those connections and caused them to overheat. Almost seems like the fuse on that circuit is not the correct size to protect the wires.

[Pursuvant]

12 hours ago, shinyribs said:

Wow, those connectors got hot!... Almost seems like the fuse on that circuit is not the correct size to protect the wires.

That sir, is a great point. It bothers me, if a spark, when the tank is on reserve and full of fumes... 

I took lots of pictures

[Triple Jim]

5 minutes ago, Pursuvant said:

That sir, is a great point. It bothers me, if a spark, when the tank is on reserve and full of fumes... 

I took lots of pictures

I've never liked the idea of an electric fuel pump inside a fuel tank, but you don't seem to hear of tanks exploding.  I wouldn't design them that way though.

[klx678]

That and it seems a lot of performance cars run external fuel pumps too.

 

[Lone Wolf]

12 hours ago, shinyribs said:

Wow, those connectors got hot! 

Looks like corrosion to me.

I have not personally experienced this problem, but the darkening is evident on a wire that is not even connected (in the center, between other 2 pair of wires).

The resolution of photos is not great as posted - maybe higher res would reveal more.

As a diagnostic, I would be curious if any of that darkening comes off with rubbing compound.

I have a high power USB microscope that I use for sharpening knives, and I would be curious what that stuff looks like up close. If it looks burnt, or like a rusty old piece of metal underwater.

A search of "fuel pump corrosion" then "images" shows some possibly similar corrosion, some of it attributable to ethanol

Ethanol attracts water. When the two get together, they create the perfect environment to grow a type of bacteria called acetobacter. After getting drunk on their EPA-sponsored kegger in your gas tank, the acetobacter excrete acetic acid. And acetic acid is very corrosive.

E-10 Alive: The corrosive damage ethanol gasoline does to your fuel pump

---

Looking at the fuel pump in the photo, how old would you say it is? Its a nearly-new fuel pump from a 2003 Harley...

 

[Pursuvant]

7 hours ago, Lone Wolf said:

Looks like corrosion to me.

I have not personally experienced this problem, but the darkening is evident on a wire that is not even connected (in the center, between other 2 pair of wires).

The resolution of photos is not great as posted - maybe higher res would reveal more.

As a diagnostic, I would be curious if any of that darkening comes off with rubbing compound.

I have a high power USB microscope that I use for sharpening knives, and I would be curious what that stuff looks like up close. If it looks burnt, or like a rusty old piece of metal underwater.

A search of "fuel pump corrosion" then "images" shows some possibly similar corrosion, some of it attributable to ethanol

Ethanol attracts water. When the two get together, they create the perfect environment to grow a type of bacteria called acetobacter. After getting drunk on their EPA-sponsored kegger in your gas tank, the acetobacter excrete acetic acid. And acetic acid is very corrosive.

E-10 Alive: The corrosive damage ethanol gasoline does to your fuel pump

---

Looking at the fuel pump in the photo, how old would you say it is? Its a nearly-new fuel pump from a 2003 Harley...

 

a closeup of "burn" markings....

and they are not burn markings!!!

See that light red circle? I used a razor knife and barely scrapped that little square "notch shape" in the corrosion. It comes off easy, because it seems to be something other than "discolored plastic", on the surface of plastic. Directly underneath the scraped notch area, you can see the plastic is not discolored by heat at all. And on the inside of this spot on the connector, under the red notch (but on the other side of the plastic i.e. the inside surface of plastic that is exposed to fuel) it has the same discoloring.

I guess it is bacteria (wow I can hardly believe it) and it's on the outside surface of the plastic in the area of electrical activity (the un-insulated wires in the plastic connector). Maybe electrical activity plays a role? 

Fascinating, @Lone Wolf for the win! Never would I have guessed such a thing called "acetobacter". Just a great interesting observation from Lone Wolf

 

[Lone Wolf]

4 hours ago, Pursuvant said:

in the area of electrical activity

Or just in the area of something vulnerable to corrosion or attacked by acids.

Nylon - Plastics are pretty inert, as glass would be. 

This unused connector pin in the center has a similar appearance to the others that do conduct electricity, but there is "less there" to create the advanced discoloration around it. Have to look at it with magnify glass to be sure

 

Another reference on this relating to fuel pumps and ethanol https://www.underhoodservice.com/ethanol-damage-to-fuel-pumps/

Copper and bronze do not stand up well to corrosion in the first place. Since copper and bronze are used in electric fuel pumps and the coils in the injectors, corrosion can be an issue.

Edited June 28, 2023 by Lone Wolf

[Pursuvant]

5 hours ago, Lone Wolf said:

Or just in the area of something vulnerable to corrosion or attacked by acids.

Nylon - Plastics are pretty inert, as glass would be. 

This unused connector pin in the center has a similar appearance to the others that do conduct electricity, but there is "less there" to create the advanced discoloration around it. Have to look at it with magnify glass to be sure

 

 

A high resolution pic below (as good as my acceptionally average Moto G can capture)

It seems our world's fuel transfer infrastructure is infected with acetic acid bacteria - pipelines, rail cars, tank trucks, and Pursuvant's moto fuel tank. It eats ethanol and cr#ps CO2 & water - source wikipedia

I added a search tag for "fuel pump corrosion".

 

[Lone Wolf]

With the connectors removed, clean shiny copper is contrasted with surrounding area.

There may have been some resistance, resulting in partial power to the fuel pump.

[shinyribs]

On 6/28/2023 at 11:48 AM, Lone Wolf said:

Looks like corrosion to me.

I have not personally experienced this problem, but the darkening is evident on a wire that is not even connected (in the center, between other 2 pair of wires).

The resolution of photos is not great as posted - maybe higher res would reveal more.

As a diagnostic, I would be curious if any of that darkening comes off with rubbing compound.

I have a high power USB microscope that I use for sharpening knives, and I would be curious what that stuff looks like up close. If it looks burnt, or like a rusty old piece of metal underwater.

A search of "fuel pump corrosion" then "images" shows some possibly similar corrosion, some of it attributable to ethanol

Ethanol attracts water. When the two get together, they create the perfect environment to grow a type of bacteria called acetobacter. After getting drunk on their EPA-sponsored kegger in your gas tank, the acetobacter excrete acetic acid. And acetic acid is very corrosive.

E-10 Alive: The corrosive damage ethanol gasoline does to your fuel pump

---

Looking at the fuel pump in the photo, how old would you say it is? Its a nearly-new fuel pump from a 2003 Harley...

 

Well, that's just fascinating. 

 

Every day is a school day! 

 

I didn't think too much about the brown on the white housing. You scuz like that pretty common on things, but I really thought the wire insulation was bubbled and burnt. 

 

I blame Pursuvant for misleading me

Edited June 29, 2023 by shinyribs