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Discussion Starter #1
Just returned from a trip to Maine and on the way back, even though the BC miles to empty read out indicated 157 miles to go, and the gas gauge indicated just over 1/2 I ran out of fuel at 10pm in the middle of nowhere in upstate NY. 3 hrs later I was back on the road and when I filled up the gauge went to full and the bc gave a reading of approx 240 miles.
I've fille dup a few times since but am not sure whether to trust the gauge reading, the bc reading or neither. Currently I have 142 miles on this tank, the bc reads 125 miles to empty, which, when added, seems to give a correct reading, however the gauge doesn't really move much off just over half. Going down to Maine I filled up often and the gauge and bc seemed to work in tandem quite nicely. Now, maybe because I am watching it like a hawk, it seems that the gauge is not moving at all and the bc gives slight variations but generaly moves downward.
What would cause the gauge to give false readings? and is there a quck fix for this "problem", Or was I just not watching the gauge for a long while when blasting through the lovely mountains of New Hampshire, Vermont and upstate New York?
If anyone has experience with faulty gas/mileage readings I would love to receive the benefit of that experience.
Thanks in advance as always.
Joel
 

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Gas Gauge

I had the same problem. I also was putting to much faith in the BC and ran out of fuel. I did manage to limp it in to a gas station..... (always go with the trip meter)

I took it to the dealer and told them what was happening. They tried to fix it but they failed 2 times. SO they ended up replacing the guts of the fuel gauge floats inside the fuel tank. The recalibrated the system and it works perfect... so far that is the only fix that I could find. It was about $400 to fix but extended warranty covered it....
 

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After a time, if you get fuel overspill into the charcoal canister, a vacuum situation happens where the tube that holds the float for the gas gauge starts to collapse, thereby preventing the gauge from showing the proper fuel level. I saw the problem fixed by removing the tube and gauge, drilling a few small holes in the tube and, using a large sheet metal screw as sort of a slide hammer, pulling the indentations out of the tub, making it straight so that the float moved freely again. I hope this makes sense, it is one of those things that is easier to do that to describe.
 

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starky said:
Just returned from a trip to Maine and on the way back, even though the BC miles to empty read out indicated 157 miles to go, and the gas gauge indicated just over 1/2 I ran out of fuel at 10pm in the middle of nowhere in upstate NY. 3 hrs later I was back on the road and when I filled up the gauge went to full and the bc gave a reading of approx 240 miles.

Just curious Starky, but how much gas did you put in after it ran out. Was it the full 6+ gallons or less?
 

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Discussion Starter #5
Dochatley said:
starky said:
Just returned from a trip to Maine and on the way back, even though the BC miles to empty read out indicated 157 miles to go, and the gas gauge indicated just over 1/2 I ran out of fuel at 10pm in the middle of nowhere in upstate NY. 3 hrs later I was back on the road and when I filled up the gauge went to full and the bc gave a reading of approx 240 miles.

Just curious Starky, but how much gas did you put in after it ran out. Was it the full 6+ gallons or less?
When I was on the side of the road with the trooper we had just come back from purchasing 1 gallon or so. When I got to the next station i put in close to the full 6 gallons.
 

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Discussion Starter #6
I thin k you've hit it.

Daman858 said:
After a time, if you get fuel overspill into the charcoal canister, a vacuum situation happens where the tube that holds the float for the gas gauge starts to collapse, thereby preventing the gauge from showing the proper fuel level. I saw the problem fixed by removing the tube and gauge, drilling a few small holes in the tube and, using a large sheet metal screw as sort of a slide hammer, pulling the indentations out of the tub, making it straight so that the float moved freely again. I hope this makes sense, it is one of those things that is easier to do that to describe.
Since this has started happening I can now hear a vacuum release when I open the filler cap. That suction noise wasn't there before, but now, I guess after my last larger than normal overspill from the top of the fill area, it is creating the vacuum that you are refering to.
Your explanation is clear to me. Thanks. Maybe this is the first stage of the charcoal (?) cannister/filter problems.
How would I go about removing the inner tube from the tank? If it is really involved maybe I shoud just leave it to the dealer.
Also, if a vacuum is created then there is the possibility of the engine being starved of fuel. Had this happen once with my ST, where the filler cap hose was twisted and essentially pinched off the fuel suppley on interstate 87.
Is this that type of potential problem or is it only isolated to the float tube?

It's amazing how a little info on the money makes me feel better.
Thanks
 

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Discussion Starter #7
How easy is easy?

Daman858 said:
it is one of those things that is easier to do that to describe.
Daman858 do you think this can be done with a shop? and exactly how easy is easy?

Thanks
 

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I saw it done at a tech session by, if memory serves correct, our Rick Cavanaugh (rickcavanaugh on the list). It seemed a pretty easy job. You might PM him and see if it was him and if he can give you pointers.

You must strip away the tupperware and the fuel gauge and its tube are right on top the gas tank and come off easy enough. I think a shop would want to replace the tube. I'll check the parts list and see what the cost is.
 

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Discussion Starter #9
Daman858 said:
I saw it done at a tech session by, if memory serves correct, our Rick Cavanaugh (rickcavanaugh on the list). It seemed a pretty easy job. You might PM him and see if it was him and if he can give you pointers.

You must strip away the tupperware and the fuel gauge and its tube are right on top the gas tank and come off easy enough. I think a shop would want to replace the tube. I'll check the parts list and see what the cost is.

I know that my local dealer says that taking the tupperware off is 2 hrs which will translate into approx. $170 plus whatever else they will want for the tube etc.
Now is probably as good a time as any to learn how to take the thing apart. Maybe just the thing to do on a sunday.

I'll PM Rick and see if he can help.

Thanks for your suggestion.
 

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You have described a clasped fuel tank. The charcoal canister gets clogged and the fuel tank draws a vaccuum as it empties. The tank collaspes and crushes the fuel sender.

If you remove the right and left tupperware panels and then the stingray, the fuel sender is on the right topside of the tank.

Remove the wire, and the bolts attaching it.

Pull out the sender.

The sender should be round. You will find a crushed area. Drill a small hole 1/16 in. and put a small screw into the hole. Use a pliers to pull out the dent. Also use your hands to make it more round. The metal is VERY thin it is easy to change the shape. Once the float inside moves freely, you are done bending.

Clean the unit with rags and compressed air and reinstall.

The cause of the problem is the clogged canister so that needs to go. It is not needed unless you are extremely concerned about air pollution and do not mind getting stuck without gas. GET RID OF IT!
 

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I don't think the dealer will disable the charcoal canister as it is part of the emission system of the bike. Your best bet is to find another LT rider that lives close by that is not afraid to work on the bike and both of you go through the process to remove the canister. You can find the directions for a Canistorectomy here.
 

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Discussion Starter #12
Next week I'll get on it

Out of town for a few days. I'll try this operation next week and hopefully won't have any problems. If I do I'll know where to turn.
Thanks for the diagnostic help.
Joel
 

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Discussion Starter #14
Felt Like I really got to know her

starky said:
Out of town for a few days. I'll try this operation next week and hopefully won't have any problems. If I do I'll know where to turn.
Thanks for the diagnostic help.
Joel
Just a quick update on my collapsed gas float tube and cannister problems:

Began July 19th 7 am to begin taking top box off etc to do the cannister removal, had instructions from this site to help. Went smoothly. Feeling fortified by that experience, only 1.5 hours from start to finish. I tackled the removal of the tupperware, left and right top and bottom left, ( didn't realize until it was too late that the bottom left didn't have to come off to remvove the uppers). 3 hours later the panels were removed and the removed float tube revealed EXACTLY what was diagnosed on this site! Crushed tube, just north of center, no float action. Put the little hole in, pulled it out a little, peaned the tube around to remodel it round, voila, float floats freely, even though there is a slight hesitation as it passes the centre point. Hopefully that won't be a problem with making a proper reading on the gauge, but, we'll see.
Put everything back together July 20 7 am - 10:30 am, am left with only 1 LITTLE "AL" screw which must be the one for the upper right hand side hole under the plastic wing area. I couldn't get that hole's alignment straight and it seemed relatively insignificant to warrant removing everything so that it could be fitted. ( hope I'm right, if not, and if anyone knows otherwise, please let me know and I'll start again)
So, after approx. 7 hrs the job seems done and I'm ready for a ride.
Thanks for all the help with diagnostics and solutions.
Once you get the large lady undressed you really feel like you know her much better. Next time will be smoother, faster and funner!
JS
 
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