K11 Owners Group

joeangi · Posted: Mon May 04, 2009 1:37 pm Post subject: Fuel tank normal?

I started the bike today. I had installed an aftermarket fuel pump, as per the many posts. Bike started up right off, and runs nice and smooth.

My question is, I notice a lot of fuel spraying the right wall of the tank, some dripping off the top of the tank in front of the filler opening. Is this just fuel being returned to the tank, since it is just at idle? I also notice that I have a exposed nipple (heavens) in front of the fuel filler opening. Is this normal? I only put about a gallon in. I think I remember the K100 fuel swirling when running, so maybe I just do not have enough fuel in it?

Thanks for any insights.

Joe

Jim · Posted: Mon May 04, 2009 4:17 pm Post subject: K11 fuel system

Joe - there's a thing call a "shed biscuit" in the tank that has a nipple that sprays the unused gas back into the tank. If the shed biscuit is damaged, it can spray fuel out other places than the nipple.

BMW put out a service bulletin years ago that deals with return fuel from the shed biscuit - but which is only effective if the shed biscuit is not leaking. The fix is to install enough fuel line (it has to be the right kind - it's immersed in gasolene) to return the unused fuel down near the bottom of the tank.
_________________
Jim
1997 K1100LTSE 94,000 - still has gremlins!
1995 R100RT Classic 16,650 crashed - repaired!
1992 K75RTP 46,000

"We shall not all die, but we shall all be changed."

joeangi · Posted: Mon May 04, 2009 4:33 pm Post subject:

Dear Jim,

Thanks for the reply. What does this "shed biscuit" look like? When I had the fuel pump out...everything looked good in the tank. Should the excess fuel be coming down out of the open nipple?

Thanks,
Joe

Jim · Posted: Tue May 05, 2009 12:22 am Post subject: fuel tank

Joe - it's kind of hard to see - you have to look way up in the front of the tank near the top - maybe a mirror and flashlight when you don't have a full tank. I looked in the fiche, but couldn't find it in any of the diagrams...

I'm not sure which direction the nipple pointed originally - I know it has to be bent down a little to install the hose and clamp.
_________________
Jim
1997 K1100LTSE 94,000 - still has gremlins!
1995 R100RT Classic 16,650 crashed - repaired!
1992 K75RTP 46,000

"We shall not all die, but we shall all be changed."

joeangi · Posted: Tue May 05, 2009 11:29 am Post subject:

Thanks Jim, I will get a mirror in there this week and see where it is coming from....

Joe

joeangi · Posted: Wed May 06, 2009 1:47 pm Post subject:

Got into the tank this morning. When I turn on the key, I get fuel out of the top pipe....am I supposed to have any fuel line on this?

This nipple also has no line attached to it. I assume it is not supposed to.

Thanks for any advice.
Joe

Jim · Posted: Wed May 06, 2009 2:30 pm Post subject: fuel tank

Joe - you only need fuel line on the nipple if you're having a problem with gas being drawn out of the fuel tank vent while you're riding. If you're not having a problem with that - no fuel line needed.
_________________
Jim
1997 K1100LTSE 94,000 - still has gremlins!
1995 R100RT Classic 16,650 crashed - repaired!
1992 K75RTP 46,000

"We shall not all die, but we shall all be changed."

joeangi · Posted: Wed May 06, 2009 5:06 pm Post subject:

Thanks Jim....I will run it as is. Just thought it was weird to see gas dripping from the top of the tank, when you engage the key

Joe