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Discussion Starter #1
I just returned from a 4K mile summer trip. For the first time in 5 years and 70K miles my LT exhibited a problem. On several mornings during initial fire up my 2002 LT leaked fuel on the ground? I peeled the plastic on the clutch side and could find no reason??? The fuel leaks over the front timing chain cover and valve cover creating a 6 inch diameter spot on the ground. The leak stops after about 30 seconds? What's really weird is that it does it in hot and cold weather conditions and not every time I start it in the morning. Once the bike been running during the day it never reoccurs.

I suspect that the cold start enrichment fuel circuit must have a loose connection, cut in a hose or bad O-ring? But for the life of me I don't understand why it doesn't repeat at every start up. This problem occurred on my second day out of a 14 day trip. After not being able to locate the problem on the road, I simply rode it and noted the time it occurred. The bike runs beautifully as usual at all other times.

I plan to tear all the plastic off now that I'm home and try a cold start up test when I can see the fuel lines.

Any collective wisdom on this subject? Intermittent electrical problems I'm more than familiar with, but an intermittent fuel leak is just seems weird.

Anyone experienced this? Let me know, maybe you can save me some time and point me in the right direction.

It's a good thing I'm not a smoker, as lighting up a morning cigarette when starting the bike could have been fatal!!!
 

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May be fuel rail ORing

I had some [but not all] of the symtoms you've describe on my '01 last year. After I replaced all the fuel injector ORings, my leak stopped completely.
 

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Discussion Starter #3
Thanks Ray. That's one of the areas I have considered checking too.

What I can't rationalize in my head is why it quits leaking in such a short period of time and is intermittent to boot? It quits too soon for any engine heating to tighten up a tired O-ring by my thinking?

But, if I'm in this far, I'll definitely change them.

Thanks for the feedback.
 

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When things "heat up" they tend to seal a little better... I bet when you remove the tank and get a god look you'll find there's a significant buildup of fuel residue by the leakiest one.

replace 'em all at onec.
 

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Discussion Starter #5
To all who may or may not care.

After tearing down the LT I discovered that my fuel leak was simply a loose hose clamp on the pressure line to the injector rail. All Injectors looked good with no evidence of leakage. Even wiggling each injector while the bike was running showed no signs of leakage. The stock BMW clamps will bottom out and no longer squeeze the hose. I removed the hose to insure the hose was not split or cracked and was still soft. I also checked the plastic nipple on the fuel rail and no sign of damage. Installing a worm gear style hose clamp solve the whole issue.

Unfortunately (or fortunately?) I broke a quick disconnect coupling horsing the fuel tank around so I could run the bike and still see the fuel rail assembly.
To my surprise my BMW dealer offered up metal quick disconnect couplings instead of the original plastic ones as replacements. I've also changed all my fuel line related clamps to worm types to stop any future similar problem.

Back on the road again, yee haw!
 

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old1951 said:
To all who may or may not care.

After tearing down the LT I discovered that my fuel leak was simply a loose hose clamp on the pressure line to the injector rail. All Injectors looked good with no evidence of leakage. Even wiggling each injector while the bike was running showed no signs of leakage. The stock BMW clamps will bottom out and no longer squeeze the hose. I removed the hose to insure the hose was not split or cracked and was still soft. I also checked the plastic nipple on the fuel rail and no sign of damage. Installing a worm gear style hose clamp solve the whole issue.

Unfortunately (or fortunately?) I broke a quick disconnect coupling horsing the fuel tank around so I could run the bike and still see the fuel rail assembly.
To my surprise my BMW dealer offered up metal quick disconnect couplings instead of the original plastic ones as replacements. I've also changed all my fuel line related clamps to worm types to stop any future similar problem.

Back on the road again, yee haw!
Well done. I had been trying to visualize how fuel might get to the valve cover and front timing chain cover, and was having a hard time. I had gone off on a wild speculation of a tiny hole in the left side of your fuel tank near the top, blocked cannister which was pressurizing the tank, and fuel squirting out of the hole only when the tank was full or the bike was parked on a surface with a particular inclination. Loose fitting on the fuel rail makes a heck of a lot more sense! Thanks for letting us know.
 
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