My gauge was tracking fine - full range. During one fuel stop on my last trip it wouldn't go above 2/3 full and now this condition persists. It tracks fine below 2/3 full. Anyone know where the sender is located?
Mike
Mike
fuel gauge tops at 2/3 full
- Thread starter SpyderMike
- Start date
Although it's certainly annoying, it's not THAT big of a deal if your fuel gauge only registers the bottom 2/3 of the tank. For that is the most important part. Having a fuel gauge that only registers the top 2/3 of the tank is bloody useless.
My Pantera had the same problem as you have, and I lived with it for many years before finally replacing the sender, which fixed it. Examination showed that the internal rheostat on the old sender had partially come apart, and the contact was only making contact on the bottom 2/3 of the arm's travel.
FWIW....
My Pantera had the same problem as you have, and I lived with it for many years before finally replacing the sender, which fixed it. Examination showed that the internal rheostat on the old sender had partially come apart, and the contact was only making contact on the bottom 2/3 of the arm's travel.
FWIW....
Hi Mike -
I hear you...however, that top 1/3 of the gauge is good for about 200+ miles in my car and I like to know what I have got. I usually refill at the half mark, so this condition limits me.
Regards,
Mike
I hear you...however, that top 1/3 of the gauge is good for about 200+ miles in my car and I like to know what I have got. I usually refill at the half mark, so this condition limits me.
Regards,
Mike
Mike,
First off, 200 miles on a third of a tank! Wow, I would love to get that much from a FULL tank.
On my GTD the gauges started to stick (I eventually discovered) and wouldn't show more than half full. I took them apart and adjusted the needles (carefully and slightly) and they work like a charm now. Of course, mine are almost 20 year old Smiths which yours probably aren't, but I just thought I'd mention it just in case.
I too started at the sender and found that the resistances at full and empty were as expected, so that led me to the gauges and/or the small voltage stabilizer (which tested fine).
Good luck resolving it.
Mark
First off, 200 miles on a third of a tank! Wow, I would love to get that much from a FULL tank.
On my GTD the gauges started to stick (I eventually discovered) and wouldn't show more than half full. I took them apart and adjusted the needles (carefully and slightly) and they work like a charm now. Of course, mine are almost 20 year old Smiths which yours probably aren't, but I just thought I'd mention it just in case.
I too started at the sender and found that the resistances at full and empty were as expected, so that led me to the gauges and/or the small voltage stabilizer (which tested fine).
Good luck resolving it.
Mark
Thanks Mark!
My gauge used to read full until 125 miles and then start to catch up - until at about 1/2 tank and then it tracks fairly linear. The first few stops, I would fill when the needle hit 1/2 and confirmed this was about half tank based ont he volume replaced. So the gauge was reading about 2/3 full after 200 miles. This may have been an early indication of what eventually happened.
I averaged about 25 MPG for the 1100 trip based on the fuel receipts and the mileage.
Thanks for the tip. I will keep it in mind.
Mike
My gauge used to read full until 125 miles and then start to catch up - until at about 1/2 tank and then it tracks fairly linear. The first few stops, I would fill when the needle hit 1/2 and confirmed this was about half tank based ont he volume replaced. So the gauge was reading about 2/3 full after 200 miles. This may have been an early indication of what eventually happened.
I averaged about 25 MPG for the 1100 trip based on the fuel receipts and the mileage.
Thanks for the tip. I will keep it in mind.
Mike
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Mike:
To answer a question you had in another post, the fuel sender in right tank under the right side fuel tank access panel that is on the wide panssenger side sill. It is there on both right and left hand drive cars.
To answer a question you had in another post, the fuel sender in right tank under the right side fuel tank access panel that is on the wide panssenger side sill. It is there on both right and left hand drive cars.
Thanks Mike!
Jack Houpe
GT40s Supporter
There are a couple problems, #1 if you have and EFI car and your fuel return is plumbed on the left tank (I think they all are) then the left tank will always have more fuel in it and the right will read differently because its the one with the fuel sender unit. #2 There is about 5 gallons trapped in the tanks due to the rake of the car and the fuel tank plumbing. Kirby S. had a great idea to put a T in the cross over line and this will allow you to use more of the fuel trapped in the tank. #3 The fuel gauges that come with the car are not programmable. The gauges that some of us have changed out to can be calibrated at empty and full giving you a full range of the tank fillment (Kirby if this is not a word kiss my ...) . I have changed my fuel sender to a capacitance type probe used in planes and boats. I have not driven the car since so can't answer if there are any problems or not.
I calibrated (I use that term loosely) mine by bending the arm the float is attached to. Registers a little optimistic above half tank but, empty is engine quits. There is still non-usable fuel in tanks but, its just that non-usable. Personally I think the "E" (push or tow) side of the scale is more important than the "F" (go fast and run) side. Worked fine to Road America and back.
John
John
I have Smith guages (electric) and I just discovered the fuel guage now only reads one tank (passenger side). When I hit the first click on the fuel pump switch (driver side tank) the needle no longer reads like it did. In fact it doesn't move at all. Both fuel pumps are working. Obviously the guage is working but for just the one tank. Any ideas? Sending unit is my guess?
Regarding #2...
I put the 'T' in the crossover. It took more work, more time and more AN fittings than I expected, but I am sure I can definitely use more fuel that's in the tank(s)now. I plugged the crossover inlet on the left side tank.
#3...
Like others, I bent my sender float wire several times and had an 'acceptable' response. I then tried the capacitive probe type as described by Jack and Mike, but I could only get it to register over 1 1/2" of it total length. Either my sensor doesn't work or? I considered that response worse than my old sensor, so I put the old sensor in and used the new gauge calibration feature to 'adjust' for its response.
I've yet to drive it enough to see how well it works now.... I'll report back once I know.
Sorry, Jack.... that is NOT a word!
:laugh:
Later,
Kirby
