I looked for threads on replacement but came up empty (pun). Any trick to this? The sending unit is not great (a full tank reads half full), the gasket is leaking slightly (which worries me) and the insulation on the original wires is petrified. It's time for a new unit. As well, does anyone sell the big, red main +ve connector on the left side of the rear subframe which joins the wire from the starter motor to the battery? The plastic clips which hold them together cracked on mine and they will not stay mated without a zip tie. The good news is that I finished my engine out major today and the TR runs sweetly. A drive tomorrow morning is in order.
See if the information in this Mondial thread might help for the big connectors: https://www.ferrarichat.com/forum/threads/help-with-identify-these-parts-on-my-88.361432/#post-141321168
The fuel sender repair obviously needs to have the fuel drained. Be really careful, lots of people have been hurt doing this. As I recall it needs a pin socket to remove the nut that holds in the sender. . People have fabricated those and I have also used a pin wrench many times with success. The sender itself for later cars still seems to be available but I have had some repaired by instrument shops.
Unfortunately, I just drained the tanks during the major I just completed, when I changed the fuel pumps, hoses and check valves; I wish I had taken a closer look at the sender unit at that time. After sitting dry for the last few months I suspect a seal has dried out, which has caused the weeping from the bottom of the tank. Ricambi and Eurospares sell a pattern equivalent; I generally prefer OEM parts, but I am not sure the original sender for a 1991 is still available.
I looked at 2 sources. One said the early part is available and the other offered an alternative view. Good luck.
The pattern equivalents are quality units. Better materials, much better design. I wouldn't hesitate buying one. https://www.ferrarichat.com/forum/posts/147489407/
Thanks - will pick one up. Car is on the road today for the first time in 8 months. Runs and feels great. (But the fuel tank reads empty).
Box with sender units apparently arrives today from Ricambi (thanks Daniel!). Any trick to loosening / tightening the locking ring which keeps the sender in the tank? On my Porsche I needed a special tool.
It takes a special tool but I have used a pin wrench and a mallet very carefully. As Daniel if Hill Eng. makes that tool.
Get a big enough box for yourself and we can take the Testarossa for a drive this weekend. Fuel level sender is already installed and works well. Many thanks!