05' Do I really need a new fuel pump?

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mjones35

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Houma, LA
I noticed fuel leaking from under the tank. My thought process was take it to the shop and if it's an easy fix, I'm out an hour or two labor. If its more complicated....... well. They said it is the fuel pump that is leaking. Its only a plastic "stem" like piece that is leaking, but I can't just fix that, I need a whole new pump. Discusted, I brought the bike home and paid them for an hour labor. I have the ability (with the help of past posts on this site) to do the job myself. If I do need a new pump, can I do better than $450? I know I'll get alot of ribbing from you more experienced guys, but I'm willing to take it if one of you can save me some bucks.

 
For a pump source I'd look yourself at the various online parts resources we linked here. Your mantra should be "McCoy, McCoy, McCoy...".

I'd wonder more WHY a piece of plastic on the fuel pump is broken. It's not something that just breaks in my experience and not something that easily can be broken off unless somebody did something stupid while lifting the tank. Nor have any of us observed a design or longevity issue there.

Finally, it *may* be fixable if you can glue it. Seems like a *possible* fix with JB weld if you can fully fill the crack. Or at least worth a try when facing a $400 plus repair bill. Pulling it from an empty tank is not an onerous job--about similar complexity as a TBS or a park plug change....just little more delicate.

 
For a pump source I'd look yourself at the various online parts resources we linked here. Your mantra should be "McCoy, McCoy, McCoy...".
I'd wonder more WHY a piece of plastic on the fuel pump is broken. It's not something that just breaks in my experience and not something that easily can be broken off unless somebody did something stupid while lifting the tank. Nor have any of us observed a design or longevity issue there.

Finally, it *may* be fixable if you can glue it. Seems like a *possible* fix with JB weld if you can fully fill the crack. Or at least worth a try when facing a $400 plus repair bill. Pulling it from an empty tank is not an onerous job--about similar complexity as a TBS or a park plug change....just little more delicate.





Thanks, Ill try some of those. As for how it happened. My guess is the other day, when I was doing wheelies might have done it, even though I never set the front down real hard.

 
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I noticed fuel leaking from under the tank. My thought process was take it to the shop and if it's an easy fix, I'm out an hour or two labor. If its more complicated....... well. They said it is the fuel pump that is leaking. Its only a plastic "stem" like piece that is leaking, but I can't just fix that, I need a whole new pump. Discusted, I brought the bike home and paid them for an hour labor. I have the ability (with the help of past posts on this site) to do the job myself. If I do need a new pump, can I do better than $450? I know I'll get alot of ribbing from you more experienced guys, but I'm willing to take it if one of you can save me some bucks.
It all depends on which "stem" is leaking, and why.

This is the bottom (outside of tank) end of a Gen I fuel pump.

DSC04254.JPG


The nipple at the top of the picture is the outlet side of the pump going to the fuel rail on the left side of the bike. The nipple at the bottom of the picture is the fuel return coming from the fuel rail on the right side of the bike.

Which one is leaking?

If it's the top/delivery nipple, you're pretty much fooked, as it's molded into the bottom flange of the fuel pump. And if it was the one leaking, I'd expect it's cracked somehow.

If it's the bottom/return nipple, you may have a chance for a fix. The bottom nipple is (not easily) removeable and there's an O-ring in the assembly that might be leaking.

Take a look at this post by Joe2lmaker who was doing some interesting things with a Gen I fuel pump flange. CLICKY The pictures clearly show that the nipple can be removed and in post #19, the O-ring is plainly visible when the nipple has been removed.

As far as a replacement pump, you can get one from Gary McCoy for about $300, but if the bottom flange is all you need, I seriously suggest looking for a used pump on eBay. I had my pump go south about 10 months ago and picked up a replacement for $100. Unless you know someone at Nippon Denso, you can't get just a new bottom flange.

'Howie

edit to add: IF you're lucky enought that it's the O-ring leaking on the return side nipple, it goes without saying to be sure to replace it with one that won't dissolve in gasoline. :)

Also, PM Joe2Lmaker about the bottom flange. He might be able to help you out in a very unsuspecting way.

 
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I made several calls around my neck of the woods and found the fuels pump as high as $690 to the lowest of $420. That's an expensive peace made mostly of plastic!

 
I don't understand how a couple of wheelies could damage the fuel pump. Please keep us posted on exactly what is leaking as you look it over carefully.

 
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I have the tank off now, it wasn't obvious which one is leaking. Had to stop for dinner, didn't want to stop, but have to keep the wife happy. I'll inspect it closer after chow.

 
OK, It's obvious now. Good news, it is the bottom/return nipple. I also figured out what "FNG" stands for. I guess I'm a little smarter after I eat.

 
OK, It's obvious now. Good news, it is the bottom/return nipple. I also figured out what "FNG" stands for. I guess I'm a little smarter after I eat.
You have a perverted definition of "Good news". :D

Good luck getting that O-ring outta there. Take a GOOD look at the pictures in the link I posted. It CAN be done. Even easier if you have a trained octopus.

 
BE GENTLE removing the pump assembly from the tank. The voice of experience would tell you that the plastic gets britle over time and forcing it out of the hole will break things (like the fuel gauge rheostat). I suggest using some shim stock as a sleeve/shoe horn. DO NOT pry on it in any way or try to force it. Creaking sounds are bad juju!

_____________________________________________________________________

I made several calls around my neck of the woods and found the fuels pump as high as $690 to the lowest of $420. That's an expensive peace made mostly of plastic!
1.) The prices are exactly why the "Alternate Parts Sources" thread was begun.

2.) Expensive piece includes the pump housing, motor, fuel filter and gas gauge. Yep, it's expensive but try operating your motorcycle without it.

 
I got the pump out and the o-ring. it only took 4 jewelers screwdrivers and a few attempts to get that nipple and o-ring, and a few cus words. I'm going to try to find an o-ring tomorrow, and if no luck, then I will buy a used Gen I pump.

 
I wish I had known this was going on last night.

mjones35, you seem really motivated to get this done. What was obvious?

OK, It's obvious now. Good news, it is the bottom/return nipple.
It's hard to believe that the O-ring is leaking. I would inspect the fitting and the flange thoroughly (under a microscope if possible). Both pieces are Polyoxymethylene (POM); a.k.a acetal resin or Delrin®. If those pieces are cracked they need to be replaced. POM is resistant to solvents, so glues and epoxies don't work very well.

Finding a replacement O-ring would be easy, but you need accurate dimensions; ID, OD and cross section diameter. I don't have a disassembled flange right now or I would give you the dimensions and recommend a part #. I have a GenI fuel pump flange from RadioHowie. In fact, I also have a left over return fitting from madmike2.

We should be able to get you rolling without you having to buy a complete fuel pump.

Inspect for cracks!

 
3 hours labor to R&R a fuel pump?

If you already have the tank lifted and drained, it's a 30 minute job to replace. Maybe an hour tops from lift to lower.

 
I picked up a new o-ring today (99% sure it is the right size). I will put it all back together tonight, after another inspection of the fitting to make sure there is no crack. No matter what happens, thanks for all your replies.

 
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