fuel pump meditation challenge 101

[Zampano]

ok. So i took out my fuel pump today, and yeah... wow... a big thanks to the previous owners.

I have had a few stuttering issues starting about a week ago. However I am able to ride and have had the bike up to speed/rpm (over 75/5000). Does that mean the fuel pump has not died yet? Could I replace the strainer/damper and maybe get away? Or will I drop $90 and then find out my fuel pump was just a few weeks away from dying. I realize there may be no answer to this epistemological query  :clap: thank you.. thank you... 11 years of college and no job  :clap:

i'm debating b/c if i buy the damper/strainer from euro moto (or the whole $92 kit from the boneyard) and then the pump goes out will that damper be of use with another pump. I'm assuming it will.

thanks. The quest to camp in baja continues. I am not taking a bus down there!!

[johnny]

if this was my situation i would do this... go to orileys and score the 2 for 1 20oz techron deal... cut to top off 1/2 gallon milk jug... put to 40oz of techron in there... submerge the pump in there wired to 12v... power it up and let it run for 30 minutes...

reinstall it in the tank with your new strainer and dampner and fuel filter... strain techron through a coffee filter and refill those 2 techron bottles...

fill the tank with chevron supream with techron... put 10oz of your strained techron in there... ride it till you burned 3 gallons of fuel... repeat the fill with 10ozof techron and do it again... 4 consecutive tanks with 10oz each...

if it survives this whole deal it means the fuel system will be all cleaned out and ready for baja...

now go bust out banner grade sunrise highway sweeper madness palomar mesa grande engineers... gotts to burn up 12 gallons of fuel...

j o

[Motorhobo]

Holy s**t Johnny now I wanna do that and my fuel pump is working fine!

Zampano -- if you haven't checked your spark plug wires do that first. I added something about that to your last post from yesterday. A bad spark plug wire will cause stuttering that gets worse over time...but it actually tends to be worse when the bike is warm. Still -- it's worth checking out because its a common problem and the easiest thing in the world to fix.

Unfortunately, you need a fuel pump and running bike for that. But in my experience fuel pumps either work or they don't...stuttering is more a symptom of clogged fuel filter or ignition issues such as bad spark plug wires or plugs. If you put power to the pump and it works, do what johnny said -- put it back clean up the tank as best as you can, make sure your AAA is paid, and ride it. Then check the spark plug cables and plugs.

Disclaimer -- I'm a noob myself, so if anything I say is wrong I'm counting on smarter people than me to correct me!

[Zampano]

thanks. I like johnny's idea. As soon as i find a 12 v source i'll give that a go. I did replace the fuel filter. But ran it for a day with that shit damper in there. Not sure if a bunch of crud was pumped into it. Either way i'm not buying another right now.

Injectors off to mr injector today. So by the time they get back i'll have my new damper/cleaned tank and hopefully flushed out fuel pump.

When it's all back together hopefully it will be running well. If not I will check the wires. The dealer put plugs in when it was in for a valve check (yeah, I know, live and learn). You'd think those morons would check the wires. I trust no mechanics. As big a novice as I am, I have never seen a mechanic do work on par with what you (or at least I) do yourself. One guy at a saab dealer in Buffalo was solid but that' it. Been to a mercedes clowns in La Jolla. They have shops which make you feel you are in a master craftsman's kitchen; but they are not meticulous, all they do is take out old parts and replace with new. It is a ruse. But I digress...

Hoping to check driveshaft splines while the bike is immobile. Do you guys pull the driveshaft and do both ends? I watched a pre-buy spline check youtube by chris harris and he did the final drive and rear of the shaft but did not mention pulling the shaft. If I pull it could i end up with a circlip problem?

What's funny (or sadly not funny) is I have been to the dealer twice and not once did they mention checking that damper.

Trust your mechanic to mend your car
Bring it in to his garage
He tightens and loosens a few spare parts
One thing's fixed, another falls apart
And the rich eat you

[Motorhobo]

Chris Harris shows pulling the driveshaft in his 5-part k100 clutch spline video. personally i would pull the driveshaft and do the front...but I think it's the rear that is more prone to wear due to the action of the swingarm...as always I hope someone will come along and correct me if I'm wrong about that.

There is no circlip involved in pulling the driveshaft. It's retained in place by the swingarm at the front and the FD at the rear.

You can't check the older OEM spark plug wires for anything...something to do with impedance or resistance or some other electrical thing i don't really understand very well...they either work or they don't and there's usually a middle ground they work sometimes and sometimes not. So not to defend a dealer, but in that case they probably weren't  at fault.

[Inge K.]

There is no circlip involved in pulling the driveshaft.

Circlip at front end of the driveshaft ... part #26 11 1 451 977

-----------------------------------------------------------------------------------------------------------

If you gonna use Johnny's metod........the pump got a very good capacity.....add a hose to the outlet
that points to the bottom of the container.....or you get techron all around faster than you can say fxxx.

Also reverse the pump for a couple of short moments in the start, to release crud stuck in the inlet.

[Motorhobo]

There is no circlip involved in pulling the driveshaft.

Circlip at front end of the driveshaft ... part #26 11 1451 977

Uh oh -- I don't remember removing that to get the driveshaft out or even seeing it. The snap ring 3317 1450 836 I remember seeing but it stayed in the boot and didn't need to be removed...let me check the Baggie where those parts are stored...maybe it's in there.

Thanks for correcting, Inge...much obliged.

[Elipten]

I went through the same thing last august but did not catch it in time before pump was toast. Clean that pump well and maybe you got lucky

[Zampano]

I went through the same thing last august but did not catch it in time before pump was toast. Clean that pump well and maybe you got lucky

that is my hope. Did you end up buying an OEM replacement? I noticed euro moto has one for $129.
http://www.euromotoelectrics.com/EnDuraLast-BMW-K-52mm-Fuel-Pump-16-12-14-61-576-p/fp-576edl.htm.

my pump had basically fallen through the damper and i believe was resting on the bottom of the tank. Which would explain the occasional noise that I've been chasing (*zip ties and foam and rubber are everywhere. I need to localize noises or i'll go bonkers).

i wonder if it's possible that it could restrict its own gas supply and maybe cause the stuttering problems I was having. It also hasn't fired up as quickly as it used to. Normally I hit the starter and it's running in a 1/2 second. Lately it needs to crank for a few seconds in the morning.

I have looked in my tank 100 times and never noticed any black specks. Always appeared very clean. If that much of the damper had disintegrated over the last year you'd think I would have noticed some crud. So maybe most of the "missing" rubber had been cuisinart'd by the pump previous to my buying it; and the jackasses I bought it from just cleaned the tank. That would actually be ok b/c it's been running 18+ months. Best case scenario is that it recently "dropped" out of the damper and is sporadically sputtering when the pump happens to lie a certain way (yeah, i'm dreaming a bit).

the inlet looks very clean. that's not to say it is clean inside, but I can hope. I'm not sure I can find a way to rig it up and run it per johnny's idea. I don't have access to much. Just a street and my bike. I don't want to risk using my own battery & running it down.

To confirm, it is safe to reverse polarity and run backwards a few moments?

thanks for your help. I miss working on my old jalopy cars. This is good meditation. Zen finding, as the Cali folk out here would say. If only it were not my only transportation.

[Elipten]

Use your battery as the power source.  That will work.  I went OEM as this is my baby that I bought new in 1990 and I figured it deserved proper treatment.  I do not know about running it backwards and would not try.

Also look at replacing all the external fuel lines as old is dangerous and this is a pressurized system.  Hate to have a fire under the tank.  It has been known to happen.  Make sure you get proper fuel lines and clamps.  It is not a gravity system.

[mystic red]

Inge K Quote

Also reverse the pump for a couple of short moments in the start, to release crud stuck in the inlet.

If Inge says it's O.K. I would believe him.

[wmax351]

Inge K Quote

Also reverse the pump for a couple of short moments in the start, to release crud stuck in the inlet.

If Inge says it's O.K. I would believe him.

It's a vane type pump, It should definitely be fine for a few seconds at least.

[Zampano]

So I am waiting on my damper, etc and fuel injectors and have a question. Are the new dampers made to function swimming in 10% ethanol gas? Or will this one dissolve over the next few years? I assume the new rubber is made for new gas, but never assume...


Also, I feel there is a water/oil pump seal job on the horizon. I swear there is not a single entity on this bike that I would not, in an ideal world, recondition. I think it's time to sign up for a KTM adventure and use this as a "what to do while drinking this six pack," "excuse not to have a girlfriend" hobby.

If anyone has a couple tools, a butterknife, and a spot not on the street, and wants to earn a few hundred beans and a few cases of Green Flash, let me know. I'll buy parts and do 95% of the work. Personally, I think the way to address this bike is tear it all down and do the water/oil pump, timing chain guides, rear main seal, clutch, spline. Then hopefully done like dinner until the rear master cylinder starts *really* leaking ;] In the meantime I am going to ride the shit out of it and get my ducats worth.

thanks! The summer is upon us. Enjoy it!

[tg4360]

Pump can be reversed with no problem.  I've unlocked frozen ones that way. 

My garage buddy even has a small pot he's used to boil (yes BOIL) k bike fuel pumps in water to heat up the crapped up gas deposits to get them to turn.  He will run them for a second in water once they free up but not for long as the gas actually cools and lubes the motor.

We had my LT going a half hour after getting it to the shop this way.

If you run it in any solvent, PLEASE be very careful doing the connections... use a LONG wire to make sure any sparks don't light things up.

A switch would be even better.

[Zampano]

thanks.

I ran it backwards for 20 seconds a couple times submerged in techron. I then ran it forwards for a few minutes. No black goop came out. I had spent awhile cleaning the tank out. There was black crap in it but not a ton. Swished it around with gas, then dumped. Then repeated a bunch of times. Tank looks pretty clean in there.





I couldn't tell how "strong" the pump was b/c I had nothing to compare it too.  I was expecting a substantial flow (I had a hose attached to the outlet going back down to the bottom of the container.) It didn't do that. There was flow but no strong swirling vortex. Without the hose attached it sprayed pretty well, so it was doing something.

I thought maybe the pump was too weak but I was fed up and installed it. The bike has been running seemingly ok. I wish I knew what "ideal" was but I think if the pump were weak it would stutter or really fade on high rpms. I got it revved up pretty good it didn't fade. Not a rocketship, but again, I don't know what to expect. I was able to cruise at 80 today. Heading west in san diego is riding into strong swirling 20mph winds and not an enjoyable experience whatsoever.

p/s
Luckily no flames. I was pretty close to the battery and ground and just holding the wires.

After cleaning the tank I would have gone up like a match too. Self immolation in protest of high dealer rates.

[RetroTexan]

So just to be clear, running 12v through the fuel pump directly will let you know whether or not it's working? Any particular polarity I need to be concerned with (I noticed each lead is a different size, one requiring a 7mm and the other an 8mm to remove them). Which is which?

[Inge K.]

The terminal with the smallest dia is +.

[RetroTexan]

Thanks Inge, exactly what I needed to know!  :2thumbup: