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Thu Oct 09, 2025 8:04 pm

‘68 bug… I bought an el cheapo fuel sending unit last year and it’s junk, surprise. Any recommendations to replace it would be appreciated!

Fri Oct 10, 2025 5:25 am

Check the Samba classifieds and/or Vendors like Bug City, VWNOS, etc. for NOS or good used original German units. VDO was the original supplier I believe, so if you can find a VDO unit, probably a good chance it should work correctly.

Looks like Wolfsburg West also currently advertises one they offer as “quality replacement that WORKS, not made in China”:
https://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113919049D
Might be worth a try, as they usually stand behind what they sell (in my experience, anyway).

Fri Oct 10, 2025 10:05 am

baldessariclan wrote: Looks like Wolfsburg West also currently advertises one they offer as “quality replacement that WORKS, not made in China”:
https://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113919049D
Might be worth a try, as they usually stand behind what they sell (in my experience, anyway).

X2

Replaced the one on my '69 with the WW unit. No issues with it.

Fri Oct 10, 2025 4:24 pm

I replaced my original VDO 50 year old one in my 68 with a virtually identical new VDO unit from Heritage VW in UK.

Note they have them here:

https://www2.cip1.com/C24-113-919-049-DVDO/?srslti...vMbmwVJ960

Sat Oct 11, 2025 12:50 pm

Recently bought & install'd the WW sender, had mix'd results. More info, here:

https://www.thesamba.com/vw/forum/viewtopic.php?p=10419119#10419119

Sun Oct 12, 2025 9:01 am

Do the screw washers need to be nylon or can regular metal washers be used?

Sun Oct 12, 2025 9:12 am

You need plastic type of washer as when it compresses it fills in the gaps. I made some PTFE washers that work well without spreading out a lot.

Sun Oct 12, 2025 2:17 pm

bugger-off wrote: Do the screw washers need to be nylon or can regular metal washers be used?

On the OEM VDO sender on the 68 ONE of the washers needs to be metal to earth the sender unit. The others are “plastic” washers.

Sun Oct 12, 2025 3:55 pm

viiking wrote: bugger-off wrote: Do the screw washers need to be nylon or can regular metal washers be used?
On the OEM VDO sender on the 68 ONE of the washers needs to be metal to earth the sender unit. The others are “plastic” washers.
Correct — normally (i.e. in the original, stock configuration) one of the five sealing washers is made of annealed/soft copper, to create an electrical (grounding) path between the sender and the tank.

The tank, in turn, grounds to the body via contact w/ the clamping brackets that hold it down in the corners — always good to check and make sure you’ve a got good/clean metal-to-metal contact point on at least one of those clamping locations.

Sun Oct 12, 2025 3:58 pm

viiking wrote: bugger-off wrote: Do the screw washers need to be nylon or can regular metal washers be used?

On the OEM VDO sender on the 68 ONE of the washers needs to be metal to earth the sender unit. The others are “plastic” washers.

You can also make a new ground wire from one of the screws to something else. Thus, if you have still have a leak on that one last screw just make a new ground.

Sun Oct 12, 2025 5:20 pm

heimlich wrote: You can also make a new ground wire from one of the screws to something else. Thus, if you have still have a leak on that one last screw just make a new ground.

Mon Oct 13, 2025 4:41 am

Yeah, I've always had a dedicated ground wire for the unit, it just makes sense.

I am starting to think it's my fuel gauge. I installed the new unit and it's doing the same thing as my old one: I have at least four gallons in the tank and the gauge is reading flat-out empty. It did move from being pegged all the way to the left to empty.

My old sender did that; it would read full after filling the tank, it would just move down to empty way faster than it should.

So I still have the issue that I bought a new unit to correct.

Mon Oct 13, 2025 5:41 am

bugger-off wrote: I am starting to think it's my fuel gauge. I installed the new unit and it's doing the same thing as my old one: I have at least four gallons in the tank and the gauge is reading flat-out empty. It did move from being pegged all the way to the left to empty.
If your current fuel gauge is aftermarket, good chance it may be part of the issue as well. Likewise if you’re using an aftermarket “vibrator” (voltage regulator) unit.

Most, if not all, of the aftermarket units for the fuel gauge system on these cars are well known for being made out of spec. / miscalibrated, and giving erroneous readings (if they even work in the first place). They’re basically just junk/crap, period. :-(

Some folks have reportedly worked up elaborate schemes & contraptions to try and make these aftermarket units work acceptably well — you can search the threads and read up on them if you like. But personally, I’ve found it’s not that hard to just source good used or NOS original factory units for the fuel gauge system — these seem to usually be calibrated correctly, and work fine.

E.g. I’ve had the current fuel gauge and vibrator setup (original German units) in my car for 9+ years now, and it works perfectly. Plus I’ve got a set of confirmed working spares as well (off an old junk speedometer I picked up at a swap meet several years ago), for if & when the current ones ever fail — easy-peasy… :-)

Mon Oct 13, 2025 6:35 am

baldessariclan wrote:

Most, if not all, of the aftermarket units for the fuel gauge system on these cars are well known for being made out of spec. / miscalibrated, and giving erroneous readings (if they even work in the first place). They’re basically just junk/crap, period. :-(

I have a device that fixes all of that. Just finishing up with testing. It hooks to the back of the speedometer and replaces the vibrator. It "realigns" the gauge and the sending unit.

Mon Oct 13, 2025 8:18 am

I'll have to double-check when I get a chance but it is a factory gauge as far as I know.

Mon Oct 13, 2025 9:19 am

Something I neglected to mention was that I checked the gauge with the sender before I installed it. With the float in the up/full position, the gauge did read full. It's just after I installed it was it obviously reading incorrectly.

Mon Oct 13, 2025 9:54 am

heimlich wrote: baldessariclan wrote:

Most, if not all, of the aftermarket units for the fuel gauge system on these cars are well known for being made out of spec. / miscalibrated, and giving erroneous readings (if they even work in the first place). They’re basically just junk/crap, period. :-(

I have a device that fixes all of that. Just finishing up with testing. It hooks to the back of the speedometer and replaces the vibrator. It "realigns" the gauge and the sending unit.

Please keep us posted on this. Mine is close enough to survive on, but I'd love to be able to get it really accurate. I learned the hard way where it's limits are.

Mon Oct 13, 2025 10:23 am

bugger-off wrote: Something I neglected to mention was that I checked the gauge with the sender before I installed it. With the float in the up/full position, the gauge did read full. It's just after I installed it was it obviously reading incorrectly.

This says to me you probably have a bad ground. I had the same issue. I cleaned the contacts super well and replaced the wire ends, no more issues.

The connection also could be bad between your ODO and the body

Mon Oct 13, 2025 10:25 am

bugger-off wrote: I am starting to think it's my fuel gauge. I installed the new unit and it's doing the same thing as my old one: I have at least four gallons in the tank and the gauge is reading flat-out empty. It did move from being pegged all the way to the left to empty.

My old sender did that; it would read full after filling the tank, it would just move down to empty way faster than it should.
bugger-off wrote: Something I neglected to mention was that I checked the gauge with the sender before I installed it. With the float in the up/full position, the gauge did read full. It's just after I installed it was it obviously reading incorrectly.
So when you checked the gauge w/ the sender before installing, how far did the float arm move down before the gauge read empty? Normally, the arm should (obviously) be near or at its bottom stop when the gauge is showing empty.

Note that you can adjust the original VDO gauges a bit, if necessary (although usually not needed nor recommended) -- details located near top of this web page: https://www.speedyjim.net/htm/fuel_ga.htm

Mon Oct 13, 2025 10:28 am

I don't think it's the ground. I've tried a couple different grounds (wires and contact points) and the gauge always drops from empty and pegs all the way to the left.