fuel sending unit access

[Smurf_GT]

I have a Kirkham with speedhut gauges. My fuel gauge is not working properly. Speedhut support said I need to calibrate the fuel sending unit to the gauge. Do I need to drop the fuel tank to get access to the sending unit?

[Danr55]

In a word, yes.

[Smurf_GT]

thanks Dan

[Ron61]

I don't know if you would like this idea or not, but on my first Cobra when I had to drop the tank to get to the sending unit I cut a door in the trunk floor above the unit that was large enough to open and get it out without any problem. I had my trunk carpeted so you couldn't even see the door unless you knew where to look and all I had to do was remove two screws to gain access. It came in very handy as I had to get in there to replace one of the rubber fuel lines that started leaking and instead of spending all that time removing the tank to get to it I had it done in about 15 minutes.

Ron

[Smurf_GT]

Ron, I would do that but I dont want to guess where the proper placement of the access hole should be.

It looks like I can calibrate the speedhut fuel gauge but will need to fill the tank and empty it to set proper F & E gauge calibration. That should be less work than having to drop the tank which requires draining the fuel.

[Ron61]

That is great if you can calibrate it without dropping the tank. As for the hole, while I had my tank down I measured everything including how wide and long the hole would need to be to make it easy for me top work on the unit and then I cut the hole before putting the tank back up so I could see if I had it correct. Fortunately, and unusual for me, I had it perfect. I also had a drain plug installed in the tank when I had it out as that pumping it out by the input and then refilling it was a pain.

Ron

[FWB]

Ron, you had help from those Shasta Mountain fairy monkeys, that's why it was perfect

[rodneym]

Smurf,
DO NOT drop the tank. The senders are capacitance types, IIRC. Try this link to calibrate the gauge...
https://www.youtube.com/watch?v=16-i8zBLqgA
Calibrate for Empty (or as empty you want to be when the gauge reads 'E'). You don't really want to be empty, ever. Then fill up and calibrate for Full. For me, empty is about 5 gallons.
The shape of these tanks don't help, either. Due to the sloped bottom, they 'empty' (per the gauge) quick.

[Smurf_GT]

rodneym

I saw that video. I watched it again. I will do it the way you suggested.

Thanks for the advice!

[Smurf_GT]

Originally Posted by rodneym

Smurf,
DO NOT drop the tank. The senders are capacitance types, IIRC. Try this link to calibrate the gauge...
https://www.youtube.com/watch?v=16-i8zBLqgA
Calibrate for Empty (or as empty you want to be when the gauge reads 'E'). You don't really want to be empty, ever. Then fill up and calibrate for Full. For me, empty is about 5 gallons.
The shape of these tanks don't help, either. Due to the sloped bottom, they 'empty' (per the gauge) quick.

Followed Speedhut instructions. Still doing the same thing. I need to figure out if the gauge or the sending unit ( or wiring) is defective. Wont be driving it much more this season as its getting cold and rainy.

[Phx Mike]

What exactly is wrong with your gauge Smurf? I calibrated mine (Kirkham fuel gauge built into the speedo) and the procedure was a bit different than the video.

[Phx Mike]

Calibrating the gage in my car was a bit different than what is shown in the video link attached above. My car has the odometer and fuel gauge built-in as a small LCD screen in the speedometer. There is a button under the dash that cycles the gauge through its various modes including trip odometer, fuel gauge, and peak speed indicator. In order to get mine into calibration mode, I have to turn the key on while pressing that button. Doing this brings up a menu on the small ECD screen. One of the options is a speedometer calibration, the other is a fuel empty calibration, and the third is a fuel full calibration.

Once you have selected the appropriate calibration you want to perform, it calibrates the fuel gauge for that mode it to the current fuel level. Therefore you calibrate the fuel full level when your tank is full, and the fuel empty level when your tank is empty (or close to it - as noted above you never want to be totally empty). The full calibration is easy, Just do that after you fill up. For the empty calibration, I was too lazy to drain the tank, so instead I filled the tank and drove approximately 350 miles (my car has the 42 gal tank). Then I calibrated the empty level before I filled it up. I ended up putting about 30 gallons in, so empty on my car means there’s about 10 gallons of useful fuel left.

Hope this helps.

[HI Cobra]

I don't have a fuel gage so I don't have to deal with that. I do have the 42 gal
tank so I start looking to fill up whenever I pass about 200 miles on the odometer
since last filling. So far so good on that method, which I learned many years ago
the hard way due to unreliable gages/senders and still do now as an old habit.

[Phx Mike]

Originally Posted by HI Cobra

I don't have a fuel gage so I don't have to deal with that. I do have the 42 gal
tank so I start looking to fill up whenever I pass about 200 miles on the odometer
since last filling. So far so good on that method, which I learned many years ago
the hard way due to unreliable gages/senders and still do now as an old habit.

Agree -practically speaking that’s what I do as well. Despite my gauge being ‘calibrated’ a) it is hard to see while driving, b) it moves around a lot while driving (will go up and down quite a bit based on temperature, acceleration, cornering, etc) and c) I am ready to get out of the car and stretch my legs after 2-3 hrs driving anyway

[Smurf_GT]

Originally Posted by Phx Mike

Calibrating the gage in my car was a bit different than what is shown in the video link attached above. My car has the odometer and fuel gauge built-in as a small LCD screen in the speedometer. There is a button under the dash that cycles the gauge through its various modes including trip odometer, fuel gauge, and peak speed indicator. In order to get mine into calibration mode, I have to turn the key on while pressing that button. Doing this brings up a menu on the small ECD screen. One of the options is a speedometer calibration, the other is a fuel empty calibration, and the third is a fuel full calibration.

Once you have selected the appropriate calibration you want to perform, it calibrates the fuel gauge for that mode it to the current fuel level. Therefore you calibrate the fuel full level when your tank is full, and the fuel empty level when your tank is empty (or close to it - as noted above you never want to be totally empty). The full calibration is easy, Just do that after you fill up. For the empty calibration, I was too lazy to drain the tank, so instead I filled the tank and drove approximately 350 miles (my car has the 42 gal tank). Then I calibrated the empty level before I filled it up. I ended up putting about 30 gallons in, so empty on my car means there’s about 10 gallons of useful fuel left.

Hope this helps.

Mike, I will check that out. My Speedhut speedometer does have a small screen. Ill will check and see if it has a fuel setting. My dash does have a stand alone fuel gauge like the video shows. Appreciate the input.

[rodneym]

Smurf,
I didn't realize you meant the fuel gauge in the speedo.
I've dealt with Speedhut when getting some gauges refaced and reprogrammed. They were great to deal with. Try 'em. They'll walk you through it.

[Smurf_GT]

Originally Posted by rodneym

Smurf,
I didn't realize you meant the fuel gauge in the speedo.
I've dealt with Speedhut when getting some gauges refaced and reprogrammed. They were great to deal with. Try 'em. They'll walk you through it.

rodneym,

Yes they have a good support line. Ill check out my spedo and see if it has the fuel setup. Thanks for the input.