low fuel light

[Nails]

I got around to pulling the fuel level sensor(s).

Regarding the actual gage: the sending unit has stops to limit the range of the float. Mine were well placed. Just when the float hits the top stop, the gage reads right on the "full" mark. Likewise for "empty". The tank obviously has more room above and below the range of the float. I'm not going to screw with bending the float wire to try to make it read the full range -- doubt if I'll be able to get much out of it.

Regarding the low level light: mine doesn't light even with the sensor out of the tank. I found this cheapo alternative, which I'll try. https://secure.cougarpartscatalog.com/fm-ef008a.html $21.56 with shipping -- beats the hell out of $160. I don't know whether it's the same (tiny) size as stock, but sure looks the same. Hopefully, I'll just need a spot of solder to hold the unit on it's little stalk, and a simple solder electrical connection (under a cover held in place with bend tabs).

There are other sensors for more than double that. If I didn't think they were the exact same thing, I'd pay for higher quality. I mean, I'll start relying on this light, then it'll fail and leave me stranded again. Story of my life.

These are temperature sensors, perhaps explaining why they come on gradually.

[Barry]

I appreciate all the effort you're putting into having everything function on your bike. What I'd like to know is if there is a wire at the sending unit that could be grounded or opened that would cause the low fuel light to function? I suspect I have a continuity issue between the low fuel light and the sending unit. Thank goodness the fuel gauge works fine.

[Nails]

It's grounded to a metal stalk affair. Just one wire (see image). Maybe that wire is broken, but I don't know how you'd tell the difference between that and a dead thermister.

Maybe you have a problem somewhere later in the harness. But I see a lot of other threads about a dead thermister. Would hate to buy a whole new $160+ sending unit just for that.

At any rate, it's easy to pull it out and look.

[Barry]

Doesn't the thermistor go open or to ground when it functions? If that assumption is correct, shouldn't there be a way to provide an electrical path bypassing the thermistor and making the light turn on the dash? I'm looking for a simple test to prove the trouble into the wiring harness or the thermistor. I've replaced the sending unit once with no improvement. I can run totally out of gas and never get a light.

[Nails]

I think it's normally open but don't know. The link for the one I bought had good information, but I'm not sure it addressed that. (The one I bought might be backwards, for all I know.)

If you pull the assembly, it's very easy to short the thermister. And getting to the plug is more than 90% of the job of just pulling it. You have to remove the front seat, which requires removing the rear seat, which requires removing the trunk. Pulling the assembly out of the tank is just a matter of spinning four 8mm bolts.

[Nails]

I can tentatively report success. I plan to haul around some spare gas to find out for sure.

With the old thermister, the dash only lit up under two circumstances: when I turned on the key (before starting -- this made me think it was working ... NOT); and when I shorted the thermister out of the circuit. With the bike running, the dash light was off even when the entire sensor assembly was out of the tank and hanging in the air.

With the new thermister and the bike running, the dash light was on when the sensor was out of the tank but off when in the gas. Just like it should.

The new thermister appears to be identical to stock. Required easy soldering. (I mounted the thermister a little higher on its stalk, given reports of the light coming on just as you're already out of gas.)

If your low-fuel light doesn't work (comes on with the key but never with the bike running) ... and if you're one of us who even cares about it ... then I recommend this $21.56 (at my door), low effort repair.

[Nails]

I had a low tank and rode until the red light came on ... which was about 100 ft from the end of the lane. The light went out on the side stand.

This time, my light came on with a little over 4 gallons burned, about the time it pins "empty". So, I wish I'd put the thermister a little lower on the stalk. Maybe I'll change that one of these days.

But I'm glad to have the idiot light. Because, you know ...

[godseeking1]

my fuel light came on but so dim i didnt even notice i.t but when i did ut o tooooo late! and guess what !!!! at only 186 miles
so so much for using mileage. i figured i had at least to 200~! but i was on a 75 mph road going across Kansas at 80+ into i guess was a bigger head wind than i thought
so sadly my 45+mpg 87 voyager ended up only getting 30 that day! luckily a local farmer gave me a gallon at no charge!

[cranky]

.. go to a scamping store, REI, etc... I carry 2 - 1.5L alum cylinders, campers
use 'um for white gas.... with gas and seafoam in it...

Used it many times for other folks, not so much for me...
did it when I had my Nomad with a 5 gal tank and at best 40mpg...
and fuel injected with pump in tank... how much gas?????

Rt 6 between Tonopah and Ely, Nv is @185 miles... can give ya pause... otherwise.....

You have plenty of storage, mine sit in the back of a saddlebag, side
by side..... FWIW

[Nails]

... or just fix the low fuel light so it works right.

[cranky]

... IIRC, a low fuel lite has very low combustion... GBG

Was at a rally in Taos, came home the northern NM route 64 over
to Page, AZ, wanted to see the horseshoU bend, nice... while going
along 64 it went up quite a waze... mid June, put my nylon liner in my
mesh jacket, and turned on my heated hand grips... real cool...

Also had to stop and wait a spell while the cowboys cleared a
lane for me so I could get thru the cattle... real nice trip!

You live out that way?

[Nails]

I remember you mentioned that ride before. Yes, 64 is a swell road -- the first couple hundred times. I drove it all the time with work.

But now that you mention it, I really could use riding on it.

[cranky]

.. yes, it was a memorable ride, very nice!!!!!!

https://2.bp.blogspot.com/-VGC9FqJqDSw/ ... %2B116.jpg