fuel pump problem

I still think it would be worth a shot to give it a try. I have spotted this pump being used on a fuel injected 950 KTM. Maybe it was being used in conjunction with the electric "high pressure" pump? It was a Dakar bike with quite a few tanks. That's what gave me the idea of trying to make it work.

This fuel injection stuff offroad is new to me. How much pressure is needed to power a small throttle body? Heck for 20 bucks a simple pump would be worth a try at least. Not trying to waste anyones time……..

ballisticexchris wrote:

I still think it would be worth a shot to give it a try. I have spotted this pump being used on a fuel injected 950 KTM. Maybe it was being used in conjunction with the electric "high pressure" pump? It was a Dakar bike with quite a few tanks. That's what gave me the idea of trying to make it work.

This fuel injection stuff offroad is new to me. How much pressure is needed to power a small throttle body? Heck for 20 bucks a simple pump would be worth a try at least. Not trying to waste anyones time……..

You will find that trying to use the Mikuni is a waste of time for fuel injection purposes. The R/X uses 3 bar pressure (about 45psia) at the injector and the Mikuni D44-211 can, at best, deliver 3.2 psia. The Mikuni can be a fine pump for moving fuel around but it is in no way ever going to function as the sole source of fuel pressure for a fuel injection system.

daggone928 wrote:

ballisticexchris wrote:

I still think it would be worth a shot to give it a try. I have spotted this pump being used on a fuel injected 950 KTM. Maybe it was being used in conjunction with the electric "high pressure" pump? It was a Dakar bike with quite a few tanks. That's what gave me the idea of trying to make it work.

This fuel injection stuff offroad is new to me. How much pressure is needed to power a small throttle body? Heck for 20 bucks a simple pump would be worth a try at least. Not trying to waste anyones time……..

You will find that trying to use the Mikuni is a waste of time for fuel injection purposes. The R/X uses 3 bar pressure (about 45psia) at the injector and the Mikuni D44-211 can, at best, deliver 3.2 psia. The Mikuni can be a fine pump for moving fuel around but it is in no way ever going to function as the sole source of fuel pressure for a fuel injection system.

That's a lot of pressure! Oh well. I guess the one I saw on the fuel injected KTM 950 Dakar bike was used for moving the fuel from those huge aux tanks…….

looking at a 2008 R: Q4, header, tuner
any way to confirm if issue is present other the long ride (snow on ground)?
cost of fix if needed?
other things to look for?

I finally have my bike back together and running. I found a used WR125R pump on eBay and figured it looked similar so I decided to take a chance on it as all I was in need of is the elbow. It turned out to be the same setup. Different fuel sender (actually looked like a fuel level gauge and not low fuel indicator), pump part number was different than the 250, the little silver thing (pressure regulator??) had a different number. I managed to separate the halves of the 125 pump and insert the 250 pump in it's place. It was a very delicate task, just barely possible without breaking anything. After I had it all assembled, back together filled with fuel and running I realized the fuel line was sitting tight to the frame, slightly kinked. Pulled the tank back off and compared to old pictures, the elbow was positioned 1 notch over compared to the 250. So I had to drain the tank and pull the pump back out. I used oring picks to pry the outlet retaining tabs out one at a time and inserted .030 mig wire to hold it in place. There was just enough stretch in the fuel line to pull the elbow out and turn it a notch.

I was tempted to take the bike out to the main streets and go for a rip as not many people can say they took their bike for a ride mid-February in Saskatchewan. This would be a good winter to do it with as mild as its been.

My bike has acted up many times in the past and I've blown it off on account of my bike being an 09. Stalling followed by hard starts and even one or two occasions where I had to wait around 10-15 minutes before it would start. Normally temps near/above 100F when these symptoms have appeared.

Yesterday with temps near 85, it wouldn't start a few times. The last time took about 30 minutes to get it to start and let me get on my way from the time it stalled. I could hear a click when the key was turned on but no whir sound from the pump. When it finally did make a sound it was very low in pitch. Mixed blessing, some sound is better than no sound but it really sounded sick. Or perhaps it made me feel sick when I heard it. Well, that low pitch sound wasn't enough to make it happy, bike started but didn't last long enough for me to get my helmet on and get going. About 10 minutes later, proper sound and on my way. Decided I'd pushed my luck far enough so I hit the pavement and headed home. No problem on the 100+ mile ride home on the pavement.

While I was waiting for it to cool off, I recall reading that the problem was with early 08 models. Which lead me to the purely speculative thought that perhaps a customer demanded that they change out the pump on their 08 and the dealer switched it with the one in the 09 that was on the floor. Which turned out to be the 09 that I purchased. Again, that's purely speculation.

Looking over fuel pump issue threads today and one item really sticks out: The recall in Japan covers bikes made in the timeframe of October 16, 2007 - November 28, 2008. My 09 was manufactured 8/08. Clearly within that time frame and the VIN serial number is even in the proper range. recall link

The way the pump acted was enough that I had already decided to replace the pump. The time frame of the production period of the recall just adds fuel to the fire.

Chalk up an 09 model with a bad fuel pump.

daggone928 wrote:

[

You will find that trying to use the Mikuni is a waste of time for fuel injection purposes. The R/X uses 3 bar pressure (about 45psia) at the injector and the Mikuni D44-211 can, at best, deliver 3.2 psia. The Mikuni can be a fine pump for moving fuel around but it is in no way ever going to function as the sole source of fuel pressure for a fuel injection system.

+1 Must agree with Daggone928 here. The WR EFI system uses a high pressure system like to what is in todays cars. Operating pressure is far beyond what that Mikuni pump can produce since it's mainly designed for use with carbs.

Hi all. I have a 2011 WRX 250 I imported from New York, to Cambodia, where I live, 3 months ago. Love the bike!!! It now has 800 miles on it. Yesterday I took it for a 20 mile run. The engine got hot because the fan kicked in. We stopped for a drink. Twenty minutes later I went to start it and no luck. I did not hear the rush sound from the fuel pump. 4 hours later and many attempts at starting the bike. No luck. I had to hire a truck to bring it back home. What a mess that was. Got it in the driveway. turned the key and shsahshsh the sound of the pump was back and I pushed the starter and it fired right up. Ugg, To be stuck out in the bush for hours with no way of starting the bike is very disheartening. I will have to order a fuel pump, have it shipped here and hope that fixes the problem. I heard of this happening on a 2008 bike, but mine is 2011. What a shame because I really love the bike otherwise. If I still have problems the bike will have to go. I need to have something reliable. I paid $6,500. for the bike and $2,500 for shipping and tax. That is a lot of money for a dead bike with 800 miles on the clock!!!
cambojimmy

Well, son of a gun. I bought a used 2008 last spring and have been enjoying trouble free riding for a year. On Sunday I went out for my first good ride into the mountains and had the fuel pump issue. After about 1 1/2 hours of riding to the dirt and then about an hour of off road riding we all stopped to chat. I went to fire my bike up and all I got was a quick fire and then death. over and over, same thing a couple of turn overs and then death! no fuel! no fuel pump sound. We tried pushing it and nothing. Stripped it down checked fuses ect. Same situation when I turned on the key you could not hear the fuel pump wind up. After about an hour I got a tow out of the bush and a lift back to the city. When I unloaded my bike I thought I would just check it so I turned on the ignition and you could hear the fuel pump wind right up. WTF? I charged the battery as I had drained it trying to start it and it fired right up.

I obviously had not read this thread. So should I just replace the fuel pump? I'm in Canada so where is the best place to buy? I don't want to hold ten friends up on a ride ever again as long as I can help it.

All comments welcome.

Jimbop

I got a 2008 WR250R with 800 miles on it. Started having trouble with the bike stalling after it gets hot. It left me on the side of the road twice. After picking the bike up with my truck and getting it home it would start right up. I bring it to the Yamaha Dealer and they replicated the problem. They check the bike up and find nothing except my wiring harness has some of the wires scrapped. Looks like a critter got to them and scrapped them. It did not affect the bike since it would start right up and everything still worked fine. The dealer changed them and charged me $523. I pick the bike up today and take it for a ride. After about 30 miles the bike just dies on me on the Turnpike. I lost all power and almost get hit by a truck who was tailgating me. I got someone to pick me up and the bike. About an hour later I can hear the fuel pump this time when I turn the key. The bike starts right up. Nothing was fixed on my bike. Yamaha refuses to confirm they are having trouble with fuel pumps. I paid $523 for something that did not need fixing. Man I feel like just setting the bike on fire in front of the dealer. I'm bringing it back to the dealer tomorrow, but I have lost faith in the bike, the dealer and Yamaha. I'll never buy another Yamaha again.

I've had the same problem with my 2008 WR250R and the most recent time happened at the dealership when I took it in for an inspection. I called Yamaha and after explaining the situation to 3 different people, they told me to tell the dealer to diagnose the problem and determine if the fuel pump was defective, then have the dealer contact Yamaha. I did this and just found out today that Yamaha covered mine. I think a lot of it depends on your dealer and luck of the draw as far as who they speak to at Yamaha. Personally, I think there should have been a recall on this a long time ago and saved us a lot of hassle!

Hi all, I just wanted to update everyone on my fuel pump problem. I have a 2011 WRX, imported from New York, U.S.A. I live in Phnom Penh, Cambodia. I ordered a new fuel pump from Yamaha Japan. Part No. 3D7-13907-00 It took 2 weeks to get here. had it installed, fit exactly the same. Wow, what a difference. The SHHHHHHHHH, sound is a lot louder than before and no problems from heat. She fires right up no problem. The bike even feels punchier. I think the old fuel pump must have been defective from the start. The cost was a bitch at $385. But now I am back ripen up the streets of Phnom Penh, and lovin it. Thanks to everyone who has posted on this topic. I would have never been able to figure it out on my own.
Cambojimmy

The dealer called yamaha and told them I had a bad fuel pump. They asked the rep at Yamaha if it could be covered under the emissions warranty and they said yes without any hassle. Thought I would let you guys know in case this helps anyone get theirs covered.

I know everyone want's to get back on the bike and ride as soon as possible. But if you dont take it to the dealer and also call Yamaha about the problem it will never get fix guys/gals. That's how big companies work.

Take it to the dealer and have them fix it, someone will take notice.

Also report it to the National Highway Safety Administration. Reading around it appears that Japan actually had a recall on their bikes. I bet Yamaha Japan probably does not share all info with the global branches. Or it could just be trying to save money. Make sure you include the part about a recall in another country but not in yours for the same problem.

Best of luck to those of you still having issues, i hope i never do.

https://www-odi.nhtsa.dot.gov/ivoq/

This is a safety related event as much as they are failing.

my bike is a wr250x 2008 mfr. date of 02/08.with about 18,000 miles & yes its one with a possible bad fuel pump. Its been over 100 degrees for the past 5 days here in colorado and yes my fuel pump is not working as others have explained & yes & at high fuel demands i have notice it cutting in and out regardless of temp and no its not my FMF fuel programmer or any other loose connector/ switch. For me there is only two options.

#1 ---> tear apart old pump (more specifically the pump motor), if possible and without damage for inspection of internal components as done by draggone958, to see if i can fix the motor which of course will be the cheapest fix and quickest fix. Not expecting to be able to save this pump motor or be able to disassemble without damage but won't know until i try i have surprised myself before.

#2 ---> buy a new pump MOTOR only. ck this out:
http://www.alibaba.com/product-gs/358173173/Fuel_Pump_for_YAMAHA_motorcycle_1100.html

OMG. really $15 dollars oh, wait have to by ten min. to place an order and it ships from china.

well dam, if i only had 9 other guys that need one and know how to tear apart their fuel pump assembly to replace just motor

ok, no one left with a bad pump but me?

Go ck this site out. http://www.ca-cycleworks.com/fp-hus $130 for just the pump motor, yes this will fit in the WR250x or r. its a direct replacement. It appears the 2008 WR250x is not the only bike out there with this POS fuel pump motor part number #1100-01090, the husky also has this POS fuel pump motor and it looks like the guys at CA-CYCLEWORKS.com places an order of 10 or more and will sell one , BUT its marked up 700%

so I will attemp to tear apart pump motor and repair POS pump & will post pics on its repair/distruction
if that don't work i will order new $130 motor and install w/ pics.

MO-tarder wrote:

so I will attemp to tear apart pump motor and repair POS pump & will post pics on its repair/distruction
if that don't work i will order new $130 motor and install w/ pics.

Please post lots of pictures. And lots of descriptions about what you find.

You bet, Hopefully i can get it apart without cutting it open.

got motor apart without any damage

did not find anything broken inside, and i only went as far as taking out the impeller. here is what i found.



the other side looks like this



I have the motor apart as shown, and connected to power to listen to it and it sounded strong, so i think i am going to stop here and resurface the impeller to provide it more clearance between the pump lower and upper parts. THe impeller appears to be plastic? and the pump body appears to be magnesium? not sure, I do know there is very little if any clearance for the impeller when parts are assembled so it makes sense when temp rise's and metal expands the impeller has no room to over come this heat expansion, so after i try to lap / resurface the impeller, fingers crossed, this should fix it

Lapping the impeller surface, will be a delicate task due to its material. I will post more pictures of this next step. I will mic out the current thickness and then proceed to remove small amounts of material probably .002" to start. I will try to measure the impeller's pump housing depth (where the impeller sits inside the pump) to see if i can get a mesurement of just how much clearance there is for the impeller when pump is assembled so i can better determine how much to remove from the impeller.

I have alot of pictures of removing the motor from the fuel pump assembly, and let me say this was not easy. The only part i damaged was the retainer for removing the fuel filter, i will have to get a new one, no big deal i am sure any well equiped hardware store should have a $.10 cent common retainer. I filed it off to avoid damage to the filter.

One thing i forgot to mention, is the outer edge of the impeller (the thickness surface) did not show any signs of touching the pump housing like both of the face's showed. There was no wear marks on the round thickness surface (outer edge) only on the face's. Where those face's sit inside the pump housing, the pump housing surface also showed signs of wear. There was circle swipes (marks) showing but did not wear off the coating on the housing surface. hard to get a good pic of this its a tight shot for camera phone.

i didn't take any pics of the sides of the impeller but i can if needed. those surfaces look untouched unlike the face's of the impeller.

Makes me wonder if the protective coating on the pump housing (magnesium part) wasn't taken into account when mfr determined the tolerance of the pump housing and impeller assembly ? OF course i am just guessing, but it happens in fabrication of any part that gets anodized, powder coated or painted after fabrication then when its time for assembly the extra thickness of the coating can cause problems in assembly and fitting parts together or (IMO) take up the needed tolerance for heat expansion of moving parts. ???? again just guessing.
Would like to see inside a new improved motor that took the place of this "recalled" motor to test my conclusions.

of course after i get this back together I will put it through the HEAT test and see if i can get my bike to repeat the non start, shut down cutting in and out (very slightly) at high fuel demand riding problem its been doing to me the past couple days, now that the summer is back and commuting temp. is above 100 degrees. . OR its all for not, and i have no idea what i am talking about.

Maybe mic the thickness and outside diameter of the impeller at room temperature and then place it in warm water (same temp as a tank of hot gas ?) and measure again to see how how much the dimensions grow, if it all.

I suspect though you won't have any measurable growth of the impeller and since you can only see rub marks on the axial surfaces that the problem is not so much the impeller growing as it heats up but the the armature / motor is heating up and expanding, taking up all the axial clearance. I bet flat lapping the impeller on a piece of glass and some 320 grit to take reduce the total thickness by .001 or .002 will fix it up.

Chrispy1200 wrote:

Maybe mic the thickness and outside diameter of the impeller at room temperature and then place it in warm water (same temp as a tank of hot gas ?) and measure again to see how how much the dimensions grow, if it all.

I like that idea, but not for the impeller its plastic (?). But for the Magnesium pump housing it should work to measure how much the part grows.

Chrispy1200 wrote:

I suspect though you won't have any measurable growth of the impeller and since you can only see rub marks on the axial surfaces that the problem is not so much the impeller growing as it heats up but the the armature / motor is heating up and expanding, taking up all the axial clearance. I bet flat lapping the impeller on a piece of glass and some 320 grit to take reduce the total thickness by .001 or .002 will fix it up.

Yes, this is the same conclusion i have come too, but not the armature / motor causing this (of course it is a source of heat) as much as it is the "pump housing" swelling and stopping the impeller from pumping fuel.

LEt me define what i mean by "pump housing" PUmp housing = two piece's made of metal (cast magnesium ?) the impeller sits inside these two pieces and is sandwich inside and surrounded on all sides , the two pump housing pieces come together and touch on the outer edges so the dimension / space left inside is fixed and the impeller spins inside.
MY theory of why this pump is failing is when the heat builds and the metal parts "pump housing" expands due to thermal expansion the space that i mentioned above that is "fixed" shrinks and grabs the impeller and stops it from turning IMO.



This would explain the wear marks i seen on the face (axial surface) of the impeller. So, last night I measured all three pieces to get an idea what kind of tolerance is left for the impeller when all pieces are assembled. Those measurements should be able to confirm that the marks i seen on the impeller is in fact pump housing expanding and grabing the impeller. ????? AND was i surprised as to what i found. YES, my theory appears to have some logic to it.

here is pic of my measurements, keep in mind there is room for error in these measurements, its hard to measure some pieces due to there position inside the motor and my measuring tool might not be suited for such task. HOWEVER, my final measurements are my best guess (guess might be a bad word to use) the best i could measure down to .001" of and inch. I measured each piece several several times different location over and over and over until i felt what i was seeing and dimensions i keep getting repeated its self over and over or often enough to conclude my final numbers to use where the closest i could get to "actual" size of parts.

inner pump housing "inside diameter" (where impeller sits inside) = .994"
impeller "outside diameter" = 1.004"
clearance = .010" so when impeller is inside there appears to be .005" tolerance on each side of the impeller as it relates to the inside diameter of the inner pump housing VS outside diameter of impeller. sounds good and makes sense (?)


So, now for the area in question
impeller "thickness" = .149" easy to measure feel good with accuracy

yea it looks like it says ..150" but it must of moved it really measured .149" now for the "inner pump housing depth dimension"

inner pump housing "depth" of pocket for impeller = .148" was a number i keep getting also keep getting .149" and .150" a couple times, but its really hard to get a good accurate measurement but i feel good with using .149" cause i keep getting it so much BUT FOR ARGUMENT and error of measurement lets ASSUME its .150" and call it good.




So, what i have concluded is the impeller thichness is .149" and the inner pump housing depth = .150" which leaves .0005" of clearance on each face of the impeller when assembled into inner pump housing. WTF! The tolerance for the diameter is of the impeller is .005"(each side of diameter when assembled) and the tolerance for the face surface is .0005"

YOU DONT HAVE TO BE A ROCKET SCIENTIST MINDED PERSON TO SEE THERE IS A PROBLEM HERE! HEADS NEED TO ROLL

This also explains why i didn't see any wear marks on the outer diameter (thickness surface) but saw marks on the face surface of the impeller .010" clearance vs. .001" clearance

Actually I am surprised this pump worked at all (barely worked and bike probably under powered starving for fuel IMO), and very surprised it has 18,000 miles on it. I do feel this is why i experienced a under power feeling at higher fuel demand (highway riding) while riding and i really think this is why the pump quits when temp is very high AS yamaha stated in their recall for japan (read it somewhere on the internet so take it as you may).

Next post will be my "fix" for the tight tolerance of the impeller to pump housing relationship. of course IMO "fix".

Chrispy1200 wrote:

I suspect though you won't have any measurable growth of the impeller and since you can only see rub marks on the axial surfaces that the problem is not so much the impeller growing as it heats up but the the armature / motor is heating up and expanding, taking up all the axial clearance. I bet flat lapping the impeller on a piece of glass and some 320 grit to take reduce the total thickness by .001 or .002 will fix it up.

I agree 100% BUT, should I match the clearance of the diameter of the impeller? which is .005" each face .010" total OR should i go further or less? How much should i remove and how much might be to much before it affects function? Any ideas i can kick around would be helpful. I am over thinking this too much need some insight.

Here's where i am at so far.

should i keep going? it started at .149" and its at .145" giving .002" clearance on each face when assembled. OR should i go .003" each face or .005" each face to match diameter clearance which is also .005"? Would that be to much ?
of course i could go less and if needed redue it, but i really don't want to do this again it wasn't easy to get motor apart or out of fuel pump assembly with no damage!. Please give me your two cents, anybody feel free to chime in, I could use some help with this decision. I will assemble it tonight so hopefully someone will respond before then. CAN"T dive to work another day MUST RIDE!

I think axial clearance on this type of pump impeller is more critical than radial clearance. I wouldn't try to match the radial clearance. Too much axial clearance will reduce the pumps efficiency. I'd stop where you are right now, I think you've taken off plenty.

Agree! Thanks chrispy1200. its almost together. Tomorrow is going to be around 100 degrees, i will be able to run it and see if i can get the pump to quit like it did earlier in the week.