How to remove this tank sensor

[Downeaster]

Does anyone know how to remove this tank sensor? There are a number of things that I can turn, as you can see. Is it the 5 nuts? The whole unit? The inner plastic piece? I can unscrew them all but if anyone has the trick let me know. Thank you!

[C420sailor]

Mine is pretty similar. Had to remove the fasteners to remove it.

[tkeithlu]

It (the whole arm and variable resistor) lifts out through the hole. Remove the nuts and lift. I think that you'll find that the heads of the bolts are between the plastic base and the metal hold-down rim. If they go all the way through into the tank, then I'd expect something holding them in place.

[Downeaster]

Thanks, guys. I'm sure I would have figured it out but my first inclination was to try to rotate the entire assembly which might have degraded whatever is sealing into the aluminum tank.

Indeed, as you both stated, the proper way to temporarily remove the sensor is to remove the 5 nuts and then, basically, pull the center piece UP. There is a very tight fitting gasket that makes it seem like it won't budge so I removed the gasket first. Then the whole inner assembly is free to be lifted up.

Thanks again! :-) Really appreciate it.

[Pete7]

Tank senders are often "foxed" so they will only go back in to the same studs they came out from. There is a small difference not easy to spot in the stud spacing. Check if it doesn't quite fit.

Pete

[jimbunyard]

Originally Posted by Downeaster

...There is a very tight fitting gasket that makes it seem like it won't budge so I removed the gasket first...

Well that's a neat trick...

[Dave Lochner]

Originally Posted by Pete7

Tank senders are often "foxed" so they will only go back in to the same studs they came out from. There is a small difference not easy to spot in the stud spacing. Check if it doesn't quite fit.

Pete

The fitting looks to be a SAE 5 bolt pattern. The bolts will not be equally spaced. It helps to put index marks on the tank and fitting to make realignment easier.

[Djarraluda]

Often have an inner ring with threaded holes. It is only about 300 deg of the annulus. Trick is to unscrew 4 of the 5 bolts and just carefully loosen the 5th so you can then turn and tilt so it all lifts out.
Roger

[Nicholson58]

You will find new sending units at the chandlers with that exact flange. It’s a standard design. On my boat the tank tops are threaded.

[inspectr]

Just a suggestion
I looks like there is a dimple on the outside ring that lines up with the straight rib of the white plastic insert? Presumably the insert will only fit one way.
I'd imagine that the washers under the "Nylok" nuts hold the insert down, but you may need to use some force to break the seal of the gasket or "O" ring