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So last week I had a wee bit of fuel leaking from the tank bottom and decided to pull it out and weld it shut. The tank was cleaned out years ago and is still very clean. The leak was coming from where the suction tube support was spot welded to the bottom of the tank..... drained gas, filled with dry ice* and then welded it up.
I thought I would try to get the sending unit working but it seems to be all over the place when I check the resistance with the meter. Has anyone rebuilt one of these units and if so what parts fail? I popped off the top cover and everything "looks" good with no corrosion. I'm sure I could buy a rebuilt one, but whats the fun in that?


*Disclaimer do not weld on or take a torch to a gas tank (empty or full) take it to a professional or you risk personal injury and or death. Just because one thing works for one person does not mean it will work for you. You have been warned! I'm sure most people know this but I don't want to hear about some kid who stumbled to this site blowing his cheeks off when the tank blows up.

Somebody out there must of rebuilt one of these units before? Any thoughts?

48 is bimetal & not a typical later resistance unit so readings will be all over. There is a discussion herehttps://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=29603#forumpost29603. I was measuring around 13 ohms on a NOS unit until I assume the contacts changed with the float action and it jumped high.

Assuming the heater element is intact on each end, wiring good and contacts & ground clean there doesn't appear much to repair. About the only moving part is the cam action which flexes the bimetal so it takes longer for heater to open contacts when tank is full. If that is happening, gauge heater should also be on longer and needle should move further.

After this info was posted, someone went and tried a Ford unit as mentioned in the thread. I believe it was for a 30 something on -maybe 37-8-9 and gave the place purchased which was a Ford antique auto place. For the life of me, can't find the thread now but he reported back & said it worked. If you have better luck with search, maybe you can find it if you decide to replace -- wasn't that long ago.

Hi BBCchris
Have you tried the very simplistic method? Take out the unit connect up the electrics. Ensure a good ground point turn on the ignition and get somebody to watch the gauge as you operate the float gently up and down. This eliminates complicated resistance readings.
Good luck
Terry

I did hook it up and cycle it slowly with no results on the gauge. Also checked it on the spare cluster with no results. I'll do more research on it. Thanks for the leads.

You have to cycle it VERY slowly. I tested all my gauges before I put the cluster back in and the gauges move very slowly. I put the fuel sending unit all the way one way and waited until the gauge started moving. It takes about 30 secs or so to get the gauge all the way in position to match the sender.

This may have been done to keep the gauge from jumping around as the fuel in the tank sloshed about.

Ok, well I'll try it again. Thanks guys.