'95 K75 fuel leak

[rkasal]

Kept smelling gas during a recent cold weather ride. Fortunately, she wasn't running rich. Unfortunately, I noticed a puddle forming under the bike when on the side stand. I shut her down real quick.

Oh boy, looks like the o-ring to the fuel level sender is bad so I get to pull the tank. Everything is off except the tank and I'm going to drain her in a few minutes.

The problem, I would guess, is the previous owner (I'm second owner) put 4,800 miles on her during 12 years of ownership. Draining the tank for storage let the o-ring dry. Rubber gaskets, besides electrical switches, are made to be used on German cars and motorrads.

The leaking fuel destroyed the insulation glue on the bottom left side (left when sitting) of the tank so that'll have to be replaced. All the fuel lines and coolant hoses look good so probably will just replace the air filter while I'm in there. Hopefully, it's only the o-ring. The only other thing it could be would be a crack in the tank itself. No fuel leak at the fuel out or return lines at the top left.

I won't pull the tank itself until the parts are here which I can't order until tomorrow but will post what I find out once the tank is pulled so as to hopefully help someone else in the future.

[mrich12000]

good idea the fire value to your bum at speed is high.:lurk

[rkasal]

good idea the fire value to your bum at speed is high.:lurk

It could warm things up for a while, couldn't it? :laugh

[jcridge]

If the oring is the culprit and it is dry and cracked. I would look at the fuel lines and crank case breather as well. Are your lines soft a pliable? Nows a good time to do it!
You can install quick disconnects in the lines while you have it apart. I have a pair of disconnects with shutoffs in both sides, so its real easy to remove the tank without fuel leaking out of the lines or injector rail.

Are you going to leave enough fuel in the tank when you remove it and pressurize it to find the leak? :scratch

[rkasal]

The first pic is of the K75 with the tank off. The second pic is what the leaking fuel did in less than three minutes to the side of the intake plenum above the fuel rail. The tank insulation above was soaked with fuel.

The pics were taken by my camera phone. If anyone needs pics of anything in particular while the tank is off, or suggestions on tank removal, please inquire now. I can take additional pics while I'm waiting for parts.

The tank removal was a 1 on the scale of 1 to 10 with 10 being the hardest. The only thing I don't like is removing fuel lines that are "welded" on and electrical connections that are also "welded" on with age such as the fuel sender.

[rkasal]

Besides an obvious fire, if you have a fuel leak, shut it down right away. This cosmetic damage occured in less than three minutes that I know of.

[rkasal]

If the oring is the culprit and it is dry and cracked. I would look at the fuel lines and crank case breather as well. Are your lines soft a pliable? Nows a good time to do it!
You can install quick disconnects in the lines while you have it apart. I have a pair of disconnects with shutoffs in both sides, so its real easy to remove the tank without fuel leaking out of the lines or injector rail.

Are you going to leave enough fuel in the tank when you remove it and pressurize it to find the leak? :scratch


One step ahead of you. I had already noticed the crankcase breather was cracked and open to the atmosphere but had forgot to mention it. If this were a car, the check engine light would have been on for a long time. ;)

Appreciate the information on the quick disconnects. The hose to the fuel rail would not come off at the tank so I had to disconnect at the fuel rail. That wasn't so easy itself. I kept thinking, "I'm going to be buying a new fuel rail." Repeat ad infinitum as I was trying to wiggle it loose.

Thanks for the tip!


PS Taking the tank to the dealer as I have no way to pressurize it.