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Fuel strip zapper

JT_R1200S

Boxer Fan
I just caught this thread on ADVrider on zapping your bad fuel strip to bring it back to life, interesting....

http://www.advrider.com/forums/showthread.php?t=758453&highlight=piezo&page=17

From the ADVrider post by Kr3w:

Fuel Level Sensor Strip Repair Tool
Greetings!

I suffered the expected Fuel Level Sensor Strip failure last weekend, and after reading through this thread, I found inspiration for a fix.
I want to give a 'shout out' to JoelWisman, Old_Don, TXjames and jzeiler for their contributions--unknowingly--to me in this thread!
After reading Joel's fix using a megger and a picofarad capacitor to drop the high voltage (HV) across the broken strip, I was already thinking...piezoelectric component. We use them in aviation. So, I decided to use a very common one. A fireplace lighter. Below are the steps I took to construct the 'device'. I used common hardware found in aviation repairs, but you can substitute as needed.


This is the original fault, a bad fuel level sensor strip. Verified with a multi-meter showing an 'open' circuit between pins #2 & #3.


1. The very common fireplace lighter being disassembled. Slide the black cap forward (not shown) and remove the one screw. Note yellow arrows.


2. Splice in additional wire. I used 18 gauge wire and covered with heat shrink tubing.


3. I applied additional heat shrink tubing for added strength.


4. First yellow arrow is high voltage or self healing tape to insure a better fit. Second yellow arrow is reinstallation of the safety switch.


5. Slide the black cap back on and reinstall the screw.


6. I used some connector pins flatten out with a vice. You could use smaller automobile blade type connectors too. (check the fit before crimping to the wire)


7. Be sure to cover the pins with heat shrink tubing to prevent electrical arcing between the two pins.


8. The completed fuel level strip repair...err...device.


9. Gas tank almost full (fill it up if you can) and battery disconnected. Install the 'device' between pins #2 and #3, order does not matter. UPDATE: Pull the trigger 4 to 6 times (feedback from other ADV members suggest this is the average) and remove. Since your here go ahead and install the 'device' on pins #1 and #4 (the heater strips). Again, pull the trigger 4 to 6 times and remove. Reconnect the fuel level strip connector and battery. (I always disconnect the battery when performing electrical work, but it is not required for this fix)


10. Success!! Result after using the 'device'. The bike should be on the center stand and the side stand MUST be up. You must start the bike and let it cycle through the preprogramed 90 second fuel sample for the fault light to extinguish.
Congratulate yourself on saving $142.00 for this repair! Use the money saved by taking your mates out for a pint!
The 'device' can emit a small HV charge. Please use responsibly around children and small animals!
__________________
'09 GSA
'92 K75s

"If loud pipes save lives...imagine what learning to ride could do!"
Kr3w screwed with this post 06-12-2013 at 12:13 PM Reason: Feedback from you guys. Thanks!
 
I read this in the past. It's interesting, but I'd be happiest if there was a conclusive explanation for why it fixes the strip.
 
I read this in the past. It's interesting, but I'd be happiest if there was a conclusive explanation for why it fixes the strip.

A little prior experience with a similar phenomenon and some guesswork:

In a former life I made repairs to individual conductors in telephone cables. One method to locate trouble was to briefly apply 600 dc volts to two conductors that were known to have a spot with faulty insulation. At the fault, the current would spark through the weak insulation and weld the conductors together. Apply a tone to the wires, follow the tone with an inductive pickup until the tone stops, and you've located the trouble spot. The weld would be a little ball of copper dragged from the conductor by the electrons flowing from one wire to the next.

Some technicians tried using this technique to repair a pair of conductors, one of which had a small crack (aka high resistance open) causing static. They would connect the ends together at the far end of the loop, apply the high voltage at the near end. The high voltage at the crack caused a spark to jump the crack, the electrons dragging along a little copper with them and "fixing" the open circuit. This was usually only a temporary fix as the conductor was thinned and brittle at the crack, often failing within a week.

I'm guessing something similar is at work when a fuel strip is zapped. I think the fuel strips are made by sealing a conductive trace (carbon?) on a plastic substrate. They quit working when the carbon cracks or perhaps was applied unevenly at the factory. The current applied by the zapper causes some of the conductive carbon to migrate back across the crack.

It will be interesting to see how long a zapper repair lasts.

:lurk
 
That's the generally accepted explanation.

The originators have reported having strips last years....
Don't recall seeing any reports either way about doing multiplr repairs on a single stip.
 
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