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Discussion Starter #1
OK guys, I took a 200 mile round trip to Gonzales today. I filled up before I left and the gauge started acting weird. It never registered all the way full then slowly fell to the white area for 50 - 75 miles then slowly came up to 3/4. It then settled at around half for 100 miles then dropped to the white at about 130 miles. I went ahead and filled up again and could only get 3.19 gallons in.The gauge went up to 3/4-7/8. How does the gauge work? Weight of fuel on a sensor, float gauge, calculations taking in account the phase of the moon or what?

Thanks, Robert
 

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Wrencher Extraordinaire
2005 K1200LT
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It is a float inside a metal tube. Have you noticed any "whoosh" when you remove the filler cap? A clogged charcoal canister can cause the tank to collapse and dent the sending tube.
 

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Discussion Starter #3
jzeiler said:
It is a float inside a metal tube. Have you noticed any "whoosh" when you remove the filler cap? A clogged charcoal canister can cause the tank to collapse and dent the sending tube.
No, no whoosh. Where is the tank vented? The cap? How do I test?

Thanks, Robert.
 

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Do a search for "Canisterectomy" that will tell you how to deal with the charcoal canister that John mentioned. If there is no woosh then the canister isn't clogged. However you could still have a bent fill tube, just caused by something else. Sometimes when filling the tank the filler nozzle if inserted far enough can bent the filler tube if you apply downward pressure while filling the tank.
 

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Discussion Starter #5
johnbaker15 said:
Do a search for "Canisterectomy" that will tell you how to deal with the charcoal canister that John mentioned. If there is no woosh then the canister isn't clogged. However you could still have a bent fill tube, just caused by something else. Sometimes when filling the tank the filler nozzle if inserted far enough can bent the filler tube if you apply downward pressure while filling the tank.
Thanks, I will do that. The EPA does not have all the answers!
Robert
 

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Scouter-50 said:
Thanks, I will do that. The EPA does not have all the answers!
Robert
Robert also try a search for "bent filler" or something like that and you will find threads that talk about the filler being bent and how to fix it. You wil need to take the tupperware off and get the gage out of the tank to repair. Folks have done the repair if bent or you can buy a new one.

Good luck post if you need more direction. :)
 

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Robert,
I experienced the same issue on my last trip. The gauge would slowly drop to the white area, then after a few miles slowly creep back to a more sensible reading. I knew from my trip odo that there was still plenty of fuel so I just kept rolling. It repeated this behavior from time to time for the rest of the trip home. The problem on my bike turned out to be a bit of corrosion in the fuel gauge connector at the tank. This "system" is heavily damped in order to prevent the gauge needle from jumping around with the float movement (which moves very freely). Consequently, the needle will move very slowly as the resistance in the circuit changes. The sender is at its highest resistance when the tank is empty and conversely is at its lowest resistance when the tank is full. The corrosion adds resistance to the circuit, plus it can create an intermittent connection. I believe what I saw (and you are seeing) is the gauge slowly responding the this intermittent connection while riding plus some small additional resistance which prevents the gauge from going full scale when the tank was full. The fix was simple: clean the connector contacts, add a few blobs of di-electric grease, replace all the tupperware then get back to riding :)

Hope this helps,
Les Willey
00 K1200LT
 

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must be something in the airwaves, I'm having the exact same problems with my fuel gauge. The first time this happened I actually thought I lost fuel somewhere! Thanks for the tip. ED
 

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Discussion Starter #9
LGW said:
Robert,
I experienced the same issue on my last trip. The gauge would slowly drop to the white area, then after a few miles slowly creep back to a more sensible reading. I knew from my trip odo that there was still plenty of fuel so I just kept rolling. It repeated this behavior from time to time for the rest of the trip home. The problem on my bike turned out to be a bit of corrosion in the fuel gauge connector at the tank. This "system" is heavily damped in order to prevent the gauge needle from jumping around with the float movement (which moves very freely). Consequently, the needle will move very slowly as the resistance in the circuit changes. The sender is at its highest resistance when the tank is empty and conversely is at its lowest resistance when the tank is full. The corrosion adds resistance to the circuit, plus it can create an intermittent connection. I believe what I saw (and you are seeing) is the gauge slowly responding the this intermittent connection while riding plus some small additional resistance which prevents the gauge from going full scale when the tank was full. The fix was simple: clean the connector contacts, add a few blobs of di-electric grease, replace all the tupperware then get back to riding :)

Hope this helps,
Les Willey
00 K1200LT
Thanks, Les. I guess I will be asking for tupperware help at the tech day Saturday. Your explanation makes good sense to me. I guess the float tube could be dented also, will let you know. Robert
 

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getting the side panels off are an easy matter that takes all of 5-8 minutes per panel. Remove the mirror (it just pops off) take out the three screws holding the air deflector and remove it. Pull the screw holding the panel. remove the turn signal and take out the two screws underneath. Take the tip over bar covers off and remove the screws under it holding the side panel. open the oddments box and take out the screws holding the cover that goes around the release button. Lift the seat to make room. Take out the screws holding the side panel. remove the screw that is under the seat where the panels meet. Take out any remaining screw I forgot to mention and pull the lock pin out of the rubber grommet at the back of the panel. now lift off the panel. There is hook tab that goes into a slot on the radio bat wing, try not to break it off getting too overzealous.
If someone elses two hands can do it, yours will too. Dont let that big girl intimidate you! You have to show her who's boss or she will take advantage of you (financially) :D

I think the canisterectomy and fuel tube may have been the first thing I fixed on my 2000.
 

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Discussion Starter #11
14wntr said:
getting the side panels off are an easy matter that takes all of 5-8 minutes per panel. Remove the mirror (it just pops off) take out the three screws holding the air deflector and remove it. Pull the screw holding the panel. remove the turn signal and take out the two screws underneath. Take the tip over bar covers off and remove the screws under it holding the side panel. open the oddments box and take out the screws holding the cover that goes around the release button. Lift the seat to make room. Take out the screws holding the side panel. remove the screw that is under the seat where the panels meet. Take out any remaining screw I forgot to mention and pull the lock pin out of the rubber grommet at the back of the panel. now lift off the panel. There is hook tab that goes into a slot on the radio bat wing, try not to break it off getting too overzealous.
If someone elses two hands can do it, yours will too. Dont let that big girl intimidate you! You have to show her who's boss or she will take advantage of you (financially) :D

I think the canisterectomy and fuel tube may have been the first thing I fixed on my 2000.

Thanks, I will print this and take it with me to the tech day.

Robert
 

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14wntr said:
getting the side panels off are an easy matter that takes all of 5-8 minutes per panel. Remove the mirror (it just pops off) take out the three screws holding the air deflector and remove it. Pull the screw holding the panel. remove the turn signal and take out the two screws underneath. Take the tip over bar covers off and remove the screws under it holding the side panel. open the oddments box and take out the screws holding the cover that goes around the release button. Lift the seat to make room. Take out the screws holding the side panel. remove the screw that is under the seat where the panels meet. Take out any remaining screw I forgot to mention and pull the lock pin out of the rubber grommet at the back of the panel. now lift off the panel. There is hook tab that goes into a slot on the radio bat wing, try not to break it off getting too overzealous. ...
I have the same problem - a bent sending tube, resulting from overfilling the gas tank which caused a clogged canister which then drew a vacuum on the tank, etc., etc.

After doing the above steps, what is required to remove the sending tube (or whatever it's called)? I have read here how to fix the dented tube but don't know how to remove it. Do I need to remove the gas tank? (I don't think so.) Do I need to drain the gas tank? (Again, I don't think so but I'm looking for details). Thanks.
 

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Just remove the bolts holding it in, unplug it and lift it out. Once its out, dismantle it and drive some gradually larger sockets through it to get it back in shape. It really isnt hard to do but just be carful not to break it. YOU CAN DO IT! I have faith!
 

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14wntr said:
Just remove the bolts holding it in, unplug it and lift it out. Once its out, dismantle it and drive some gradually larger sockets through it to get it back in shape. It really isnt hard to do but just be carful not to break it. YOU CAN DO IT! I have faith!
Sounds easy enough, and I've seen some photos on this site that show it after its removal. I take it the unit is only visible after removing the right side fairing?

I have Sears' complete socket set so I'm sure I've got the necessary items on hand to fix the dent(s). :rolleyes: Maybe there is a specific size of plastic pipe that could be used to straighten the the tube after it's removed. I'll look, once I'm into it.

Thanks.
 

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Of course you would want to make sure that you do not have a topped off tank prior to removing the float assembly! Just a gentle reminder.

John
14wntr said:
Just remove the bolts holding it in, unplug it and lift it out. Once its out, dismantle it and drive some gradually larger sockets through it to get it back in shape. It really isnt hard to do but just be carful not to break it. YOU CAN DO IT! I have faith!
 

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AlaskaFish said:
Of course you would want to make sure that you do not have a topped off tank prior to removing the float assembly! Just a gentle reminder.

John
And if one does not heed that gentle reminder, a wetter reminder will soon follow.
 

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Discussion Starter #18
LGW said:
Robert,

Have you managed to get your fuel gauge issue reslolved?

Les Willey
Not yet. I don't think corrosion on the connector is an issue. at least cleaning it did not fix it. I will pull the sensor when I change the fuel filter this weekend. And I will get to try out my new Oetiker clamp pliers.

Robert
 

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Sorry to hear your problem wasn't associated with the connector (an easy fix). It will be interesting to learn what your final solution is. Hang in there!

Les
 

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Discussion Starter #20
LGW said:
Sorry to hear your problem wasn't associated with the connector (an easy fix). It will be interesting to learn what your final solution is. Hang in there!

Les
Thanks, Les. I'll keep you posted.

Robert.
 
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