Fuel Gauge reading

[storeyn]

Hi All....


I have been suspect of my fuel gauge reading for sometime, it won’t go above half ( even though the tank tank is fuller).... I did just think it was just the amount I was putting in...but did notice it went down quite quickly to 1/4 then stops.

This morning I put a spare sender unit on, the ohm readings on the slave sender were good. When it was fully down the gauge did not move as expected, but when fully up the gauge only showed just below half.

The low fuel light doesn’t work either but that may be the bulb so a separate issue.

Just wondered if any one had experienced the same issue and had any ideas what might be causing it. It’s almost as if the gauge needs calibrating?

[tinweevil]

Hi All....
The low fuel light doesn’t work either but that may be the bulb so a separate issue.

Just wondered if any one had experienced the same issue and had any ideas what might be causing it. It’s almost as if the gauge needs calibrating?

First thing to check is the output of your voltage stabiliser, it should be 10v. 'Stabiliser' was a typically optimistic name by Lucas, an original is anything but stable. The club supplies refurbished units with modern internals that live up to the name.
Second, check the bulb.

[storeyn]

Just checking the resistance measurements on my spare sender

At the bottom of the travel it’s 273 ohms and at the top 17 ohms

The low fuel connection is showing about 3-4 ohms when it is connected.

[storeyn]

Just checked my voltage regulator and only got 5.6v... a bit low I think..

[geeksteve]

Just checked my voltage regulator and only got 5.6v... a bit low I think..

It's a sort-of-regulator that doesn't actually give a flat output. A lot of digital multimeters wont be able to read it accurately as it's a bit of a saw-tooth job. An analogue meter would give a better reading - but for the price I'd be tempted to just replace it.

[storeyn]

I have ordered a new TDC voltage stabiliser....

Just another thought, my rev counter never starts straight away normally after 20/30 seconds it starts to work.. would this be the same issue with the voltage stabiliser?

[Carledo]

I have ordered a new TDC voltage stabiliser....

Just another thought, my rev counter never starts straight away normally after 20/30 seconds it starts to work.. would this be the same issue with the voltage stabiliser?

Nah, that's just SOP! A light tap on the glass will bring it in quicker. The rev counter doesn't run through the stabiliser at all.

Steve

[Richard the old one]

When you put the new voltage regulator do not be surprised to see that your engine temperature reading goes up as the voltage regulator supplies both the petrol gauge and the temperature gauge. I am surprised you did not notice that the temperature gauge was reading low.

When it come to the rev counter all the dolomites I have had have needed a tap to get them going from time to time.

[storeyn]

My temp gauge always sits on the first segment so about a 1/4, my 1500 I had 20 years ago always sat in the same position so I didn’t really think that was low...

But guess with a correctly functioning voltage stabiliser it should under normal conditions sit in the middle of the gauge.... my new voltage stabiliser arrives tomorrow so hopefully all will be corrected

My sprint has an aftermarket combined oil pressure and temp gauge so never a problem with that gauge.

Thanks for all your help and hopefully my new VS tomorrow will bring things back to the norm....

[storeyn]

New voltage stabiliser fitted....

Temp gauge now in the middle and I have gained a 1/4 of a tank of fuel....

So good result...


I also slaved my spare sender unit on and low fuel light works now.... although based on the fact I was always showing a 1/4 of a tank less fuel than I thought don’t think I ever got low enough for it to come on....