Just asking -
You did take the shipping pin out at the bottom of the new sender unit, right?
Usually theres a sticker reminding to remove pin before installing.
It might be stuck in there, it’s a small rivet and that hole is needed to be open for float to operate as it along with a couple other holes at the bottom cap takes in gas - so make sure these are open and unobstructed.
Is your dash gauge now (or has been) inoperative or pegged at the top Full position?
When I decided to replace mine, the fuel levels seemed off - less gas than indicated and lots of sloshing at half tank caused float to wander up and down. At least that’s what I thought something was awry. First thought was clean the grounds, the terminals.
So when I replaced it, I checked the ohms on both old and new, readings were 67.5 Empty at bottom and 2.7 Full at top, this data was referenced in a Pelican post as normal or good unit range.
By the way, you don’t need to install the float sender into the tank to check if dash gauge and sender are operational. Either get a helper to read dash gauge as you slide the float by hand to the top, the middle and bottom to confirm levels are consistent. I set up my camera phone video do do this.
My new unit performed no better than the 45 yr old original. I cleaned all sender terminals and plug, removed dash gauge cleaned ground and all terminals too and still not certain it helped any but it’s important to clean these anyway as lots of tarnish can accumulate on the dash gauge. On the old unit it cleaned the thin guide wires, brush the contacts and reinstalled. It works but I can’t and won’t depend on accuracy…no more less than 1/4 tank or I’m carrying a gas jug and walking !
Also - yes… tightening the nuts at opposite sides (like wheel lugs) so it goes down evenly and don’t overdo the torque. Some even say that a bend or collapses tank in that area could cause an issue how float sets.
