Hi all,
really don't know where to post this. But my '90 K75 (Silver) fuel level float makes noise hitting the sides of the tank. I think this is what's happening as it is most obvious when the tank's been filled. The tank's filler flap is still present so I can't look in to see for sure. And this has not been an issue on my Red K75. So I'm asking if this is a common annoyance. I won't call it a problem as I don't think it is anything more than an annoyance and if that's just the way it is, I'll live with it. But if a simple adjustment somewhere would correct it I would try that the next time I have the tank open. At present the low fuel level light comes on at 135-145 miles, i.e. maybe 10 miles before I would prefer. My preference being to have it come on at 150 miles, meaning I have 50 or so miles of fuel left in the tank.

Thanks and best regards
J.Jefferies

Can you hear this when riding? If so then you should consider wearing earplugs when you ride. If you don't then you're risking damage to your hearing.

Robmack has a good write-up on adjusting the fuel level sender lighting up the low fuel lamp.

https://www.k100-forum.com/t9265-messing-with-the-in-tank-fuel-sender

duck wrote:Can you hear this when riding? If so then you should consider wearing earplugs when you ride. If you don't then you're risking damage to your hearing.

Nah, just when starting or moving around prior to going. My ear plugs are effective enough to keep out most noises once I'm over 30 mph. But before that yes.

Do you have a fuel level gauge and, if so, does it indicate the correct level?  If you don't have a gauge, then when you look into the tank is the level arm floating correctly?  I'm thinking that if the float ball itself is damaged, it might be filled with gasoline and sinks to the bottom of the tank. The way the float arm is formed makes it impossible to hit the side of the tank.

robmack wrote:Do you have a fuel level gauge and, if so, does it indicate the correct level?  If you don't have a gauge, then when you look into the tank is the level arm floating correctly?  I'm thinking that if the float ball itself is damaged, it might be filled with gasoline and sinks to the bottom of the tank.  The way the float arm is formed makes it impossible to hit the side of the tank.

No fuel level gauge, this bike has the simple fuel level low light. And while I've not taken the flapper valve out to check ,think the float is up high enough to be tapping on the top sides of the tank. Well, that's what it sounds like. When the fuel level is lower, say after 30 miles, the float isn't hitting the sides. As I mentioned before the sound can only be heard when the tank is full and the bike not moving fast. Mostly when coming off the center or side stand and when first starting off. While I doubt it, it is possible the float arm could have been bent. I was more suspecting the bottom end of the arm where it connects to the rheostat as being off.

If you think that the float arm is banging up against the top of the tank, then you can adjust the mechanical stop on the sender to limit the upwards movement of the arm.  I would test your theory beforehand though..



The tab pointed to by the BLUE arrow in the picture is the upper mechanical limiter for the arm.  Remove the gas cap to provide more access, reach into the tank and carefully bend it towards the sender case.  Make small incremental adjustments instead of large bends.

thank you, will try that soon. Just now I've got the whole garage torn up trying to make space for all three bikes. As soon as that task is finished I'll try the adjust.

best regards
J.

If it's boinking the tank when full then it probably isn't a flooded FLS ping pong ball.

Another possibility, a fuel hose or the filter, might be vibrating close to, and banging against the tank wall, or a pipe.

Hello, Also check the fuel pump rubber mount. It could be deteriated and not holding the pump firmly.

Kim Hunter wrote:Hello, Also check the fuel pump rubber mount. It could be deteriated and not holding the pump firmly.

Will check but think the mount is new(ish). Less than two years old. Unfortunately I went for surgery on my right knee today. Probably will be a week or two till I can pop the  bike up on the center stand, which is my standard of being recovered enough to ride. Which figures into this as I will need to be able to get to the tank outside the garage to check.

best regards  to all of you
J.

Hope the surgery went well and you heal up quickly.

Point-Seven-five wrote:Hope the surgery went well and you heal up quickly.

Thanks, it went well I think. I had made plans to be laid up for a week or more. Lots of frozen entrees etc. Went in at 9AM, got home at 4:PM. had a light dinner and went to bed for 6 hours. And then watched youtube. They gave me a set of crutches which I tried but they were more of an impediment than a help so racked them. They gave me pain pills which I haven't taken. Really wasn't in pain. Just waiting for the knee to heal enough to not bleed. Think I was lucky, well prepared in terms of exercise before hand, and a deft surgeon. Waiting till Monday for his exam before taking up running marathons or parking BMW bikes.

Get well soon! I didn't take pain med either for my hip replacement. Stuff makes me sick!