Author Topic: WTB: K series fuel level sensor  (Read 2684 times)

Offline Keleven

  • ^ Motobrick Curious
  • Posts: 50
WTB: K series fuel level sensor
« on: May 18, 2022, 11:17:44 AM »
I know it is far fetched, but does anyone have a used (working though) fuel level sensor? or know how to repair a break in the wire-wrap portion of it?

Thanks
  • Anaheim, CA
  • VTX1800N, WR250R

Offline rbm

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Re: WTB: K series fuel level sensor
« Reply #1 on: May 18, 2022, 03:45:16 PM »
You won't be able to repair the wire wound resistor element in the sender, so maybe just use the sender as is.  You'll still get low fuel level indication, and you'll have the gas tight passthrough connector working properly.  Why do you need fuel level indication?
  • Regards, Robert
Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline frankenduck

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Re: WTB: K series fuel level sensor
« Reply #2 on: May 18, 2022, 09:03:30 PM »
RBM, you're a more knowledgeable electron chaser than I am. I have a question.

I get that the wound wire does variable resistance out to the yellow FLS wire for the round fuel gauge.

Is the white FLS wire to the cluster idiot light connected to a binary switch with electrical timer/damper mumbo jumbo in the cluster circuitry so that it doesn't go on and off every time that the ping pong ball bounces up and down?
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline rbm

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Re: WTB: K series fuel level sensor
« Reply #3 on: May 19, 2022, 03:57:32 PM »
That's precisely correct Duck.  There are two wipers on the float arm - one that touches the wire-wound resistor element and another that touches a PCB board with tinned copper planes.  The planes are grounded and when the second wiper touches it, it sends a ground potential to the cluster.  The cluster has electronics to delay and average the reading so that sloshing fuel doesn't cause the low fuel light to blink on and off. The copper planes are adjustable so you don't have to bend the float arm to change the level at which the low fuel light illuminates.
  • Regards, Robert
Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline frankenduck

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Re: WTB: K series fuel level sensor
« Reply #4 on: May 19, 2022, 05:49:26 PM »
That's precisely correct Duck.  There are two wipers on the float arm - one that touches the wire-wound resistor element and another that touches a PCB board with tinned copper planes.  The planes are grounded and when the second wiper touches it, it sends a ground potential to the cluster.  The cluster has electronics to delay and average the reading so that sloshing fuel doesn't cause the low fuel light to blink on and off. The copper planes are adjustable so you don't have to bend the float arm to change the level at which the low fuel light illuminates.

That's great info.  Thanks.  I have a K75S that comes on with two gallons left instead of one. Drives me nuts. I just found your post at the K100 forum that shows how to adjust it.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
Buy parts here.

Offline beemuker

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Re: WTB: K series fuel level sensor
« Reply #5 on: May 20, 2022, 09:43:31 AM »
On the K1100LT I had, the fuel level sensor was so corroded I just eliminated the whole assembly and just used the wires at the pass through to get power to the fuel pump. Luckily the trip meter still worked. I couldn't see spending $200 for a new one.
  • Panama City, FL
  • '00 R1100RT,’92 K75 RT,past tense:'83 R80ST, '93 K1100LT,,94 R1100RS K75s, Honda NC700, Suzuki Bandit 1200, bmw R75/5 Honda 750

Offline Bnelson55

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  • Posts: 2
Re: WTB: K series fuel level sensor
« Reply #6 on: June 11, 2022, 09:31:00 PM »
If the OP is no longer in need of this sensor, I DO NEED ONE!! 1992 K75RT

Please contact me if you have one available, thanks!
  • CT, USA
  • 1992 K75RT

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