F800GS Wont start - Help

I have gone through a few posts to make sure I am not asking a question on a known issue here. It appears I may have a bad fuel pump or something with the tank.

So here's what happened.

I rode about 60 miles yesterday up in the hills with lots of dirt time. (west Camino Cielo area.) The bike ran just fine. Prior to heading out, I fueled up with some 92 octane in a 2 plastic fuel jug. Bike ran just fine the whole time. Started and stopped the engine twice during the ride for pics and water. Rode home, out the bike in the garage. All done. No issues.

Today. I was going to do the same ride again, but go further. So I use the same fuel can, add another gallon or so. Fill it to the red tab as usual. Roll it out of the garage and go to start it up. It just cranks and cranks. No even the slightest indication of combustion occurring. Crank crank crank. Nothing. Put it on it center stand. Crank crank crank. Nothing. Open the gas cap and crank crank crank. Nothing. Nada. No the battery is getting low. (I have a charger.)

Anyone know what the f**k is wrong? It is a 09 F800GS with 3700 miles on it. I suspect a faulty fuel pump, but not sure.

Any ideas? Oh yea, my closest dealer is 50 miles or so away and closed til Tuesday.

Thanks inmates.........

Sounds like what happened to my bike. On my bike it was the fuel pump. BMW reportedly has a new one that doesn't die with California gas.

Could also be the fuel pressure sensor. Check out this post:

http://advrider.com/forums/showpost.php?p=16171341&postcount=521

Good luck!

Thanks for the tips Yeti. I'll pull the sensor wires and check it out. Looks like that sensor runs about $150, so not the end of the world. Will check it say for sure later tonight.

In order of prevalence....

#1: stuck fuel injectors. Old glue like gas will cause this, as wil gas with the slightest trace of deisel or contaminated with many other things. Aluminum oxide from the fuel pump caused by alcohol oxygenated fuel contaminated with water will do this as well.

Solution, take of the little plastic triangle on the right side of the bike. It is the cover held on by 1 T25 screw. Look inside and you will be able to see the right fuel injector. Thump the injector repeatedly with something hard and flat while cranking the engine. Try not to bend the injector, just induce sharp shocks and it will usually in-stick.

If that works, get the fuel out of it and find fresh fuel from a diferent provider.

Riding the bike is acceptable to get the fuel out, but don't turn it off till your pouring in fresh fuel.

Buy some BMW techron and use 1oz per gallon for the next few tanks, then once every thousand miles.

#2: stuck fuel pump. Remove your fuel pump controller. It's the metal thing with fins and 3 wires plugged into it. It is under the seat and under the big rubber cap with a hose coming out of it. It is secured by 2 T20's.

Once the fuel controller is removed, unplug it's connector from the fuel pump. Needle nosed pleyers help but either way, u need to squeeze the tabs on the sides of the connector.

Once this is out of the way, rig up a way to get power from the battery directly to the terminals on the pump. Polarity doesn't matter, you want to apply power for just a second and then reverse the polarity and do this a couple of times, never longer then a second at a time. What your doing is jogging the pump back ond fourth to un-jam it. Blue bullet connectors, the crimp on sort will more or less fit these terminals. You can get those from any automotive store.

There may be some risk of fire and explosion. The fuel pump controller and ZFE act as a fuse. You will be bypassing that fuse. Under any normal circumstance the fumes in the tank will be way to rich to ignite, but under some possible circumstance, it could be ignitable. If preceding does not make sense, concider NOT doing the above. Cars and motorcycles never blow up in 49 of the 50 states, but you are in the one state it does happen, especially in Hollywood.

#3: DME brain fart. Rare, but just like windozs, the bikes operating system can crash. Unhook the battery for a few hours.

What's described above with the fuel pressure sensor failing is super rare. Less then 10 in warranty failures for the whole USA in 3 years, but it is possible. The connector for the FP sensor is behind the same cover the fuel injector is. Unplug it, if it starts and runs, that was your problem.

Good luck.

Copy, paste, and added to my Joel W. folder on my computer.

God Bless,
David

Thanks Joel!

Q: I had heard that you could hasten the reboot of the DME by disconnecting the battery leads and then shorting the leads together ... any truth to that rumor?

My BMW "wisdom of the twins" document (peppered with wisdom from Joel) is in Microsoft Word right now, but I think I can convert it to PDF, send it to my iPhone then read it on the road if need be withthe iBook app.

Joel,

Thank you for all the advise.

Question: Can I really have stuck injectors or a stuck fuel at such low mileage? I guess anything is possible, but I do only run 91 octane, but it is California oxygenated / nitrogenated fuel.

It's true, if you do it exactly how you just said to. I gave up describing how after two guys on this very forum sent me angry pm's after shorting the battery terminals or leads while still hooked up to the battery.

Funny thing is both guys refer to dealerships as "stealerships" and insist that if you want something done right, do it yourself.

Anyways, since them, I'm adding some lawyer speak and dropping any suggestions that could be screwed up lol

A stuck pump usually takes some time to occur. Stuck injectors will happen on the tank of fuel that is nasty, or over the next few at latest.

It's not a mileage thing but is sometimes a time thing, and the less mileage the bike has over time the more likely fuel system damage is to occur.

To try and keep injectors from sticking on bikes in dealer inventory, tanks are filed to the bottom of the filler neck, BMW techron is added, and bikes are stored in a temperature controlled showroom, but it still happens occasionally occasionally when the bikes are prepared for delivery with only 15 miles on them.

Thanks Joel, yeah I understand ....
I learned at 16 how much power there is in a battery when a buddy screwed up and shorted one to ground via a wrench and his wedding ring.
The resulting blister on his finger was amazing....

I wish your "stealership" was closer so I could let you steal some of my dough!

lmfao

Okay. Bike fixed and running. Simple fix really.........when fueling, put the bike on the center stand AND only fuel up to the red tab! I had the bike on the center stand and over filled it a bit. So I siphoned out some fuel, charged the battery back up and crank it a bit. Started right up on the fourth try. I should have figured as the bike is fuel injected, it need a bit of space to pressurized the tank. What can I say, I'm a n00b to riding fuel injected bikes.

Lesson learned.

Thanks for all the assistance you FF's. Anytime you get up to Santa Barbara or further north let me know, would love to hook up and ride...........

Uhhhmm......sorry, but that makes no sense whatsoever (to me). I don't think it had anything to do with being on side stand vs. center stand, or overfill fuel level. Coincidental maybe, but doesn't seem related to your "issue" in terms of cause & effect.

HF

Well, it does to me. The tank needs to pressurize, and the fuel volume was such that it wasn't able to be pressurized. Once I siphoned fuel out, it started, and runs just fine. So, if that wasn't the problem, please tell me what was.

another great post, joel.
it's been said many times already.....thank you!

Thats odd, last I checked, my manual was rather straightforward in stating to fuel the bike on the side stand. A difference between the 650 and 800?

The tank is vented to atmosphere, it is not a pressurized system.

I don't know what your problem was/is. Don't think anything was solved, per se'. Maybe not a problem that will surface again. I donno. Keep an eye on things.....watching for any other gremlins to appear as clues.

You don't need to put your bike on the center stand to refuel. In fact, sidestand is better to gain proper fill volume (hold more). I always topmine off to the max (brim) with no problems.

HF

I fueled it up on the side stand. When I put it back into the garage, I put it on the center stand. That's when I noticed I over filled it. My lesson learned is regardless of filling on the side or center stand, just fill it to the bottom of the red base.

No, I can see this guys. The bike will fill higher easier on side stand, so....

Bike is badly overfilled (above bottom of red filler neck). Then parked on center stand on a hot Cali day. Fuel expands, filles charcoal canister, next morning it won't start cause bike is sucking globs of fuel into engine.

Drain some fuel, wait some time, crank some more.... And it starts.

If this was the cause, it will intermittently run like a turd till the canister is completely purged, but then will be fine.

Impossible to say for sure, but overfilling is a possible scenario.

Castrate it! :dg

HF :jose