Fuel Tank Sender Unit

[EuropaTC]

I don't know if the Europa gauges are similar to other Smiths gauges I've had on other cars but I have a hazy memory of being able to adjust the throw of the needle by a couple of slots in the back of the gauge.  You'd have to pull it out to do it, but might be worth a look unless someone knows for sure that the Europa gauges aren't adjustable.

The downside might be that if it reads "Empty" when the float arm is fully depressed, you might end up reading 1/4 tank left......   something to play with on a rainy day ?

[4129R]

As it happens, I had a spare rusty beyond repair fuel gauge lying around in my garage.

It is simplicity itself. How it works is a mystery. Bimetallic strip heated by a coil? Does the coil magnetise or bend the thing it is wound around?

I can see nothing to turn to adjust it.

[BDA]

I believe that's the way they work. .According to this page (http://lotus-europa.com/manuals/misc/electrical/meterinfo.html) all electrical gauges work the same way.

[4129R]

I believe that's the way they work. .According to this page (http://lotus-europa.com/manuals/misc/electrical/meterinfo.html) all electrical gauges work the same way.

Thank you very much for that link. It all makes sense to me now. I can see what needs to be moved to adjust the gauge. Very similar to the way you adjust the points gap in the distributor. Stick in screwdriver and rotate.

My rusty gauge internals are soaking in vinegar to see if I can resurrect it.

Then I will pull the one in the car out and see if I can clean it up.

[jbcollier]

Or, an overly enthusiastic instrument voltage regulator.

[Kendo]

I wondered about whether the VR was involved. Which instruments are powered by the voltage regulator. And who has a mnemonic for remembering that? 

[BDA]

All the electric gauges other than ammeters and voltmeters require a VR.

[4129R]

Or, an overly enthusiastic instrument voltage regulator.

I measured the new one. It is putting out a constant 9.7V.

[4129R]

I pulled the fuel gauge apart and cleaned it up.

The needle/pointer is very delicate and easily bent.

The adjuster is a slide where you literally push an insulated Formica plate across to move the start point for the needle. 

After much fiddling and adjusting, and with a new tank sender out of the tank so fully moveable to both extremities, I have got the gauge to read full.

I will re-fit the gauge into the dash and see if it still reads full scale. At least the gauge is cleaned up and easily removeable now.

I am now awaiting the parts to sort the blocked tank pipe out. Until then, I have 1 tank and a calibrated wooden dip stick.

[jbcollier]

Oil pressure gauge is not powered from the instrument voltage regulator.