TheSamba.com :: View topic - can a tube style fuel sending unit be fixed?

Mon Jan 02, 2012 9:25 pm

hey all, I had a tube style sending unit that I tried to fix, I had apparently came detached from the inner base where this disc with a wire attached came off of the other side of the sender I guess, bottom line can I replace the wire in this thing and fix it? I soldered it back together but a little crooked the first time when I tried seeing if it would move it busted the wire so I also wanted to ask did I fudge it up by soldering it as well? and for my third question where’s the cheapest place to buy a new one? which I don’t want to do... thanks for any input.

Tue Jan 03, 2012 8:21 pm

You have long sentences friend :D . We need to know the year of your bus, i have yet to find someone who remakes the 68-71 units

Tue Jan 03, 2012 8:26 pm

therewasathreadonhereaboutfixinglaterunitsusingnichromewirefromtheelectronicsstore theearlyunitsaresimilarbutusealotlesswire waitifoundityayme :wink: :P
http://www.thesamba.com/vw/forum/viewtopic.php?t=380693&highlight=nichrome

Wed Jan 04, 2012 6:47 pm

sorry fellas new to forums and am always runing a hectic schedual. no excuse for poor writing skills tho, so i have a tube style of a 73 and from searching it takes nickle-chromate wiring. so now i need to find how what thickness and how much wire to use...anyone have any opinions?

Wed Jan 04, 2012 9:39 pm

busdaddy wrote: therewasathreadonhereaboutfixinglaterunitsusingnichromewirefromtheelectronicsstore theearlyunitsaresimilarbutusealotlesswire waitifoundityayme :wink: :P
http://www.thesamba.com/vw/forum/viewtopic.php?t=380693&highlight=nichrome :

:D :D :D :D :D

Thu Jan 05, 2012 1:12 am

So those links go to a float style type fuel sender I have one that's a tube style is this the same gauge wire?. I can prob guess on the length since it can't be too short or the wire won't connect on each side and too long would show the wire sagging...

Thu Jan 05, 2012 7:25 am

They can be fixed, I had a brand new unit that the wire broke off at the connection. I soldered it back together and it worked fine.

Fri Jan 06, 2012 9:37 am

I rewired a new one last year in order to get a better sweep of the gauge. I have some pictures somewhere and will find them and post later today.[/list]

Fri Jan 06, 2012 8:43 pm

I'm glad to hear successful results, what type of wire did u use? I heard nickle chromate works and I have an idea of the gauge of wire, but what did u use?

Fri Jan 06, 2012 8:44 pm

I'm glad to hear successful results, what type of wire did u use? I heard nickle chromate works and I have an idea of the gauge of wire, but what did u use?

Fri Jan 06, 2012 10:33 pm

Used the wire that was there, just reconnected.

Fri Jan 06, 2012 11:39 pm

OK. here you go. I went to Jacobs Online and bought the 40 gauge nichrome.

Then came the hard part. This stuff is very thin and hard to work with. You have to run one continuous strand from the top (bottom in this picture) around the bottom (top in picture) and back to the top again.

Along the way it has to go through the metal tabs of the float like this...

It has to contact the wire on both sides. As the float moves up and down it effectively changes the length or wire as so the resistance and that gauge moves accordingly.

The hard part is soldering the wires while keeping them tight. The good thing is that the minimum order from Jacobs gives you enough wire to practice with.

The trick was to put something under the springy part (on the left side in the photo) while you solder it.

It still didn't give me a full sweep on my gauge but it gave me a full to just under half sweep. It is enough so that I know where I stand fuel wise. on of these days I will mess with changing the input voltage to give me a full sweep, but for now, this works.

Sat Jan 07, 2012 1:43 am

I've looked so long for this mountain minstrel, hopfully this helps a few more people wanting to save a few bucks. you've basically covered the whole procedure with pictures. Can't thank you enough now I can get my beautiful bus back on the road agin :D

Sat Jan 07, 2012 1:33 pm

groovydoobie wrote: I've looked so long for this mountain minstrel, hopfully this helps a few more people wanting to save a few bucks. you've basically covered the whole procedure with pictures. Can't thank you enough now I can get my beautiful bus back on the road agin :D

No problem, it is nice that there was something I could give back to this site.

Sat Jan 07, 2012 7:28 pm

A little victory, I had a fuel gauge that was not moving. I took my dash apart to see if it was the gauge but everything was fine on that end. What If did notice is the amount of surface corrosion that was on the contact in on the voltage regulator (vibrator), and all the other contacts. I took the fuse box a part and found the black wire that supplied power to that circuit and found more corrosion in the fuse box. Using a cheap dremel tool the kind you get at Harbor Freight, I got out the bras wheel and started to clean up the contacts on the fuses, inside the fuse box and cleaned out with compressed air. Put it back together and lo and behold, my gas gauge now works. So if your bus has been sitting for long time, mine sat for 17 years, take some time to clean your fuse box and take your time not to cross any wires. Hope this helps guys.

Sat Jan 07, 2012 8:01 pm

Thanks for the tip on cleanin up the fuse box, I didn't thnk about doin that mine just looks old no corosion but it never hurts to polish those contacts up!

Fri May 05, 2023 8:01 am

I fixed mine just this past weekend. My gauge wasn't working at all. I had to pull the tank to replace the rubber hoses because there was a smell of fuel in the cabin and so while the tank was out, I pulled the sending unit. I tested conductivity through to ground and there was none. I did a little searching around and found that more replacement units have a second wire coming out for ground, but not the original VDO units. So I figured there was corrosion. My resistants wire was intact, so it wasn't that.

I ended up drilling out the rivet that held on both the positive and grounded the ground side. Because it's copper against Aluminium, there was significant corrosion. I re-attached everything with a machine screw and nut to hold it on tight.

Of course, in doing all this, I did break the wire from where it was soldered on. So re-soldered it, taking up the slack with the springy plate. There was still plenty of wire left.

I tested it outside the tank first and it worked fantastic! Shortly I'll have it in the tank and installed. No reason it shouldn't perform fine there as well.

I can't upload photos right now as it says I'm blocked, but will try again later.

Sat Jun 03, 2023 7:44 pm

Finally got the photos uploaded. They are here: http://www.thesamba.com/vw/forum/album_search.php?search_author=askovronek&show_results=summary