Classic cars forum & vehicle restoration.

[chestevj]

Hi, I recently bought an old British Telecom lorry, converted into a horse box. It carries two diesel tanks which are linked by a u-shaped pipe. The fuel guage only seems to register when the offside tank contains fuel - does anyone know how I can switch between the two tanks, or get the guage to register the fuel in the nearside tank?

Thanks in advance

Ness

[Uncle Joe]

If the tanks are interconnected with a crossover pipe coming out of the bottom, then there should be no need for either an extra gauge or a tank switch, as the fuel will find its own level, and be the same in both. Or am I missing something?

[chestevj]

If I tap the offside tank it sounds empty; I put 50 quids worth of diesel in the nearside tank the other day), but despite this the fuel guage reads empty. Confused!

Ta, Ness

[buzzy bee]

I would have thought like uncle joe says they will find there own level.

Maybe a dodgy gauge?

[chestevj]

Hmmm, could be....

Thanks for your help guys

Ness

[Uncle Joe]

If there is a balance pipe between the tanks, then a single fuel gauge will read for the both of them, without any need for switches, etc.

Why dont you fill the tank that you are running off brim full, and then let the lorry stand for a while, at least overnight. If the diesel seems to disappear, then its filling up the other tank. Often, the balance pipe is way to small to allow for a quick fuel transfer

If it doesn´t, follow the fuel lines, and see if there is a switch or something along them. Then you can follow the electrics from the tank pumps (if there are any), and check for switches there as well.

There are countless ways of interconnecting multiple tanks, its just a matter of finding out which one has been used! If you can give a detailed description of everything, we can more than likely solve things!

[chestevj]

Hi Uncle Joe - if the balance pipe is the long 'U' shaped one, then I suppose that would account for the lack of any obvious switches. The nearside tank has been full all week and yet the offside tank is empty (unless the transfer only happens offside to nearside and not the other way around??). I'll get underneath and try to follow the lines as you suggest.

As an aside, in front of the offside tank, attached to the chassis, are two circular reservoirs, and below those, are two 'T' shaped things... taps? (not sure what you'd call them). I dare not fiddle with anything because I've absolutely no idea what I'm doing - any idea what these are please?

Ta, Ness

[Uncle Joe]

If the two tanks that you describe look like short fat sausages, and have a metal pipe coming out, then it sounds like you mean the air tanks. If you have the possibility of posting a picture, I should be able to confirm this for you. The taps at the bottom are to release water.

When you have finished driving it at the end of the day, and you have air pressure, you simply open the taps, and the air blows out the water. When the air has stopped coming out, you close the taps. Easy

[chestevj]

A quick update on the twin tanks epic.... despite the fact that the tanks are connected by this U'shape pipe running from the bottom of each tank, it turns out that the nearside tank drainhose which should run back into the offside tank, wasn't actually connected to anything! Rather bizarrely, not to mention worryingly, the hose had been stuff up and wedged in the chassis, bunged up with a shaped piece of wood. The mind boggles! So, the upshot is, only the offside tank is in service.

Thanks to all who replied though. Run for cover though because I feel another question coming on!

Ness

[buzzy bee]

A strange running repair from some day maybe!!

The crude ones are the best!