Club 80-90 Forums

Hi, as per post title, I just wondered from those with more experience of tank replacement whether the tank sender units are generally reliable or do the 'tracks' wear out. My gauge only reads half full when filled ( in the days pre panic ) and would rather avoid dropping the tank to check the sender and reluctant to mess with the dreaded dash ribbon.

Hi Andrew,

Ive renamed it the fools gauge.
Twice now l have run out of fuel thinking l still had plenty. So l now zero the trip every time l refill and work on mileage too.
I changed the tank two years back and probably accidentally bent the float arm on reassembly.
I get very poor readings compared to how much petrol l know l have added. And slow road bends pushes the needle from side to side on the gauge.
How lucky you run LPG.

Regards
Stuart

In answer to your question,
The sensor tracks can and do wear, just the same as on any vehicle.
Especially in the area the level sensor mostly rests.

If you are a "keep it topped up" person, then the gauge may read lower when near the full mark,

I was always a "run it on vapours" person, and in my old mk2 Cavalier (lord rest it's soul) I used to get down to approx 1/4 tank and then the needle would drop to empty.

If the needle drops in unison with your mileage, then a few things could be considered.
1 - Dirty / corroded Sender plug. - corrosion would increase the resistence through the circuit and thus lower the gauge reading.

2 - Worn sender... we have already detailed that above.

3 - tired fuel gauge. - admittedly, I have run a few older cars, and gauges never seemed to fail.
Erratic or faulty gauges on a T25 are "usually" due to faulty senders, wiring or voltage regulator.
You can rule out the voltage regulator, if you run a watercooled, and the temperature gauge behaves normally.

The finger of suspicion is on the sender.

If I was setting up the gauge, I would
Put a gallon of fuel into an empty tank,
(Ensure the tank is at the same angle as it would sit in the van.)
Fit the sender and bend the arm so that it reads empty.

The importance is knowing when you are getting close to empty - not when you are close to full.

Doing what I describe means that when the gauge reads empty, you still have 20-odd miles worth of fuel to get you to a "local" petrol station.

I swapped the tank and sender a few years back. I wouldn't say they're super accurate, (the centre section on the gauge recedes faster that the top or bottom) , but other than that it's a pretty clear indicator. You should definitely get a full reading when filling the tank ! As said, going round a left hand long turn at speed will lower the gauge (sender is on left front of the tank). Taking a long right turn down hill will push the gauge up.
The sender is earthed to a chassis rail under the tank( you can't access it with tank in). That rusts and will give you wrong readings all day

Thanks for your replies, it wasn't a problem as I usually run on LPG but the nearest supply to me is now 25 miles away and has been out of order now for 2 months the nearest to our caravan is only open on week days so if I can't stay until Monday then I'm having to run on petrol there and back Think I'll have to bite the bullet and drop the tank to look at the earth as it works but is showing empty when it isn't, luckily I keep some LPG in reserve in case the gauge is telling the truth.