Mr. Jethro's Fuel Gauge Send Unit Repair Guide

[Guest]

Greetings and salutations,

Mr. Jethro has graciously allowed me to edit, convert, and host a PDF file of his excellent fuel gauge send unit repair guide on my little BikeCliff website. Thank you, Mr. Jethro, for your fine work. Now it will hopefully be easier to find and you don't have to store all those pictures. The file size is less than 500K as a PDF.

Along with links to Mr. bwringer's and Mr. robertbarr's sites, I also added a link to Mr. robertob's blog and his fine GS1000 restoration project and a link to Mr. tfb's nice Katana restoration site. If anyone has any requests, let me know.

Thanks to all of you for contributing to the collective information. Now I really should learn how to make a decent webpage.

Thank you for your indulgence,

BassCliff

[Jd Powell]

BassCliff,
Youre website is quite helpfull thank you for taking the time to set it up. I have a question for you about the fuel sending unit. I rebuilt mine about a month ago. Unfortunatly I did not mark the relationship between the float arm and the pickup arm. Now when the tank is full it reads 3/4 and when the guage says empty I am just switching to reserve. So any Ideas on how to calibrate the sending unit? Obviously I could just trial and error it. But I dont relish the idea of pulling it out 2 or 3 more times to try and get it right. Is there a specific ohm reading that it should have when the float arm is at either end of its swing?

[BassCliff]

I'm just the messenger

Mr. Jd Powell,

If your bike is like mine, resistance on the gauge side should read between 1-5 ohms when FULL and 103-117 ohms when EMPTY.

On the meter side, between the Orange and Yellow/Black wire you should see 45-65 ohms. Between the Orange and Black/White wire you should see 55-85 ohms.

I don't know of any way to calibrate the send unit other than adjusting the float wire like your bathroom toilet float. I don't see a potentiometer in the circuit diagram.



Perhaps Mr. Jethro himself will chime in. I'm sorry I couldn't be of more help.

Thank you for your indulgence,

BassCliff

[Steve]

So any Ideas on how to calibrate the sending unit? ?

Unfortunately, you just might have to have it in and out a couple of times unless you get lucky the first time. 8-[

By your description, your gauge is reading low all the time. Remove the sending unit. Bend the arm down, probably about 1/4 to 1/3 of the way from the pivot to the float. How much to bend? Move the float about an inch or so.

My personal opinion on fuel gauge accuracy is based on FAA requirements for aircraft. It only needs to be accurate at EMPTY. If you think about it, it really doesn't matter if it stays on FULL for 100 miles then takes a nosedive, as long as when it crosses into the red, it goes on RESERVE.


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