Fuel line question?

[NewtomeR850R]

I'm currently getting my r850r put back together and ready for cruising but, the hard fuel line that connects with the injector on the right side of the bike has a crack in it. It does leak, its about 1/2"-5/8" in long. Went to the dealer and you can't just buy the fuel line, you have to buy a whole new assembly including the sensor and the six lines. Supposedly you have to take apart the bike 3/4 of the way put this in. The 90$ for the part is fine but the time is crazy. My question is do any of you know of another way to fix this? Maybe cut the line and replace it with an equally strong fuel line? The line pressure is about 40 lbs so I've been told so.....Thanks guys.

[John Dickens]

Not a recommendation, just an opinion, but if it were me I would try cutting the line back to remove the crack then splice in a new section in matal or suitable plastic. Test it well before you rive away. If it doesn't work then you're no worse off.

[Joe Frickin' Friday]

Not a recommendation, just an opinion, but if it were me I would try cutting the line back to remove the crack then splice in a new section in matal or suitable plastic. Test it well before you rive away. If it doesn't work then you're no worse off.

 

Problem is that there will be no "flare" in the new ends of the hard plastic pipe. At the factory ends, there is a swelling of the diameter that prevents the clamped hose from slipping off. It's possible something could be made to last (maybe two clamps on each end of the splice?), but BMW/Bosch would not have added the flares to the ends of the stock fuel manifold pipes if they thought it was possible to get by without them.

 

Actually, now that I think about it...aren't there metal inserts in the ends of the hard plastic lines to take the clamping load?

 

Supposedly you have to take apart the bike 3/4 of the way put this in. The 90$ for the part is fine but the time is crazy.

 

No "supposedly" about it, access is not real easy. Rear subframe has to be swung up into the air (sort of like this, except you won't have to remove rear wheel or swingarm) and the airbox has to come out. That said, if you've got tools and a manual and are mechanically inclined, you can take care of this yourself in an evening.

[mshuell]

I had the exact same problem on my 1996 R1100RT. Assuming the 850 has the same setup as the 1100, here's what I did. The hard plastic line and the fuel regulator are not one piece. The hard plastic line is a shrink fit to the regulator. I carefully cut it away with a knife. I then purchased a foot of fuel injector hose at the local auto parts store. I coated the outside of the fuel pressure regulator nipple and the fuel injector with a small bit of fuel resistant Permatex. Secure both ends with hose clamps. You're done. The hard part is actually getting to the fuel pressure regulator. As was mentioned on previous posts, you have to essentially take off the back half of the bike to lift the subframe and remove the air box. Not a fun job, but doable (for me) in about 3 hours.

 

Best Wishes, Mark Shuell.

[flars]

Re: Mitch's observation. It seems to me that if you have enough plastic line exposed, and if there is no metal insert in the end of it (for strength), then you should be able to cut the line, put a bead of jb weld around the end of it to act as a flare, and put a piece of fuel line on it.

[Joe Frickin' Friday]

Re: Mitch's observation. It seems to me that if you have enough plastic line exposed, and if there is no metal insert in the end of it (for strength), then you should be able to cut the line, put a bead of jb weld around the end of it to act as a flare, and put a piece of fuel line on it.

 

For that to work, the JB has to bond with the plastic tube...and I don't think JB is gasoline-proof.

[DBG]

How about a compression coupling? It ought to be about the length of the crack, most likely longer.