Lancia Motor Club

Hi,

We have recently got our 1969 1.3 Rallye S Coupe back from the restorers. During the work the restorers had a lot of trouble with the Fuel Sender and it still appears to be malfunctioning (gauge won't go above 1/4 full)

To try and get to the bottom of this ourselves we would like to try and do some tests to work out if it is the sender which is at fault or the gauge itself. It is our understanding that the sender contains a rheostat and the gauge position reflects the current flowing controlled by the resistance of the rheostat?

If this is the case then does anyone know the resistance readings we should see when the sender is in the "full" and "empty" positions. We were hoping we could measure this on our unit and then also add these resistance values using resistors to check if the gauge read the correct value with a fixed resistance to check if that is functioning correctly?

From what we have read it looks like the S1 shares the same fuel tank as the later S2/3 but the sender is different? does anyone know if the later sender (which seems to be easier / cheaper to get hold of) can be substituted for the earlier S1 unit? See the later sender here:

https://www.ricambio.co.uk/fuel-tank-sender-unit-seal-lancia-fulvia

Thanks in advance for any help anyone can provide.

Kind Regards,

Shelley

An obvious test is too short out the signal wire at the tank to see if you get full scale deflection of the dash gauge (full = low ohm resistance on sender).

Are your gauges Veglia or Jaeger. I think veglia sender is back compatible.

As the sender has a thick rubber gasket it needs a good earth to function. Does the red light come on when low (a separate contact and nothing to do with the basic sender function).

This doesn't give resistance readings but a good way to check the sender.

http://lancisti.net/wbb/index.php?thread/10926-testing-gauges/&pageNo=1

Hi Both,

Thanks for the replies, we will run the checks suggested and report back.

The instruments are Veglia so hopefully that is good news.

We also noticed that Tanc Barratt do a "modernised" sender that looks like it has a lot less moving parts than the original and so maybe more reliable in the long term, and which is listed as being suitable for all Fulvias? Does anyone have any experience of this unit?

https://www.deltaintegrale.com/shop/lancia-fulvia-fuel-air-and-exhaust/82281074

Thank you

No experience of it but I would imagine it’s pretty good. The original senders are very irritating the way the gauge needle bounces around in response to a float on a long un-damped lever.

Thanks for showing the link, I’m tempted myself!

How would one fit the modernized sender to the tank? From (poor) memory I thought the standard one is fixed with small nuts to the tank studs. Is the base of the new sender of the right thickness to take the studs? Andrea

Just looked at the one from Tanc, and it uses the existing gauge holes.
If I'd seen this when I was trying to get my 2c gauge working, I'd have bought it.
My Berlina had the Cork float that was absorbing the fuel, and when it dried out if fell to pieces.
I sent my unit to Speedy Cables in Swansea, who fitted a plastic float and calibrated it.
So I now have a gauge that works once again  🙂
Brian
8227 8)

An update on our sender issue, we shorted out the wire from the gauge to the body and happily the gauge now reads "Full" (see attachment).

We contacted Tanc Barratt who confirmed their "modernised" sender is suitable for an S1 with Veglia instruments so we have ordered one today.

Will update once it has arrived and we have fitted it.

Thanks again for everyone's help.  :)

An update as promised, the Tanc Barrat "modernised" sender arrived today and so far it looks good, the construction of it looks really good quality.

Here are two pics of what was received and showing the resistance with the "float" at the empty and full positions respectively (the meter is set to a 2k Ohm range).

Next step is to get it fitted but that may not happen for a couple more weeks, but will provide another update when it's on.

Thanks again to everyone for their help on this.  :)

Sorry for the delay in posting another update on this, we have finally got the Tanc Barrat sender fitted and so far it appears to be working a treat!, it is really reassuring to now have a good idea of how much fuel is left in the tank!. See the photo for the sender in place.

Overall we have been very impressed with the quality of this item and would highly recommend it, it looks a great upgrade on the very unreliable looking complex mechanism of the original.  :)

Interesting post.

I have just been cleaning out the tank on my S1 and the sender was in a miserable state, I tried to clean it and it snapped. I have a substitute from an S2 which
appears the same, however, looking at your experience I think I will buy one of the upgraded units.

Hello, I am new to the club and forum and find myself with a puzzle with a S1 Fulvia Zagato being Recommissioned after many years. How does one get access to the fuel sender in a Zagato?  It seems the removal of the fiberglass "floor' over the spare tire must be removed for access. don't want to tear anything up.  Any advice is appreciated from someone who has done this job.