Nope not overthinking at all. I did the same think, but ended up just sitting with what I thought comfortable I'm still yet to fill the tank so once that's done in hoping it's sorted Sent from my Pixel 3 XL using Tapatalk
Ive had two of these from JK First one burnt out my gauge Second one bounces around that much you can't ger a fuel reading. Did buying yours from ebay sort it? Sent from my SM-G960F using Tapatalk
Unfortunately not, but it's alot more accurate now, but half a tank is still full, I think I need to bend the tabs on the sender. That's my next job anyway. Attempt to calibrate the sender. Sent from my Pixel 3 XL using Tapatalk
That eBay link looks a reasonable solution, not too expensive and spec'd for the job. I would test the new regulator with a big resistor first to make certain it's giving 6v, before wiring in an expensive gauge.
Ive just noticed that the gauges have a little opening on the rear to adjust them. it allows you to move the needle to the bottom of empty, rather than off the scale empty. assume that's what its form . might help you ? 1979 Super Viking, 2lt type 4, Automatic
Yeah I've noticed and read up on that. But very skeptical of altering the adjusters on the guage itself. Sent from my Pixel 3 XL using Tapatalk
If a spare gauge ever comes my way I plan to try and adjust mine, but Speedy Jim (RIP) recommends you don’t do this.
Playing with my guage today I noticed two things. 1. The new sender float has half filled with fuel, so that can't be helping at all. 2. The new sender goes for 110ohms empty and 50 ohms full. (Above is incorrect see update) The fuel guage works when directly wired to the guage and ground on the dash. Going to test it back on the original wiring now out the tank to see how the guage responds. UPDATE stupid me check the resistance between the wrong points. 8ohm full and 72 ohm empty. Sent from my Pixel 3 XL using Tapatalk
Looks like I'm going to have to use the adjuster screws on the guage. Sent from my Pixel 3 XL using Tapatalk
Sender floats should be sealed & not have fuel in them. I would start with a good quality sender unit. Check full/ empty resistance before you fit it. Drain the tank once fitted to get an accurate empty resistance reading. Tank empty is obviously the most important reading you need. You can then tweek the gauge to read correctly at empty. Be warned though a lot of gauges have two adjusters. One for adjusting the range of sweep and one for needle position fine adjustment.
Finally gave up. Findings are as follows. First the sender float was full of fuel, so lucky I kept the original sender which had a good float so swapped that over. I thought was the sender ohms where incorrect, stupid me wasn't using a good ground. 72ohm empty 8ohm full. Wired it up directly to the guage and managed to calibrate the guage with manually moving the sender. Conclusion is that the guage itself is not functioning correctly. The needle looked a bit damaged on the guage so tried my best to straighten it which helped a little, but the needle itself it a bit sticky, it would jump a few mm once the ignition is on and no fluid movement to it. Ohms up to the guage are spot on and the regulator is giving the correct 6V. So time to find a new fuel guage. For now I've just added a wire from the guage down the back of the dash so I can quickly check the ohms, to save reaching up inside. Sent from my Pixel 3 XL using Tapatalk
Success with the gauge. Highly recommend BUS-OK.NL , they immediately sent me another gauge when the first didn't work, no quibble. Highly recommend them. On the downside, think the new voltage reg has failed after a 20 min drive. I have a 7806 reg. Can I use it as a DIRECT REPLACEMENT for the standard one? I. E. That tiny little 7806 instead of the big clompy VW original one? Am asking in case I've misunderstood. I have a matching heatsink for it. Jim 1979 Super Viking, 2lt type 4, Automatic