Leaking fuel sending unit

MarkB

Hello all. Last year I had my fuel sending unit replaced under warranty because it wasn't reading right.

The unit that was put in was leaking gas through the bolt holes on the flange mount off the fuel tank.  The mechanic put some kind of sealant on the flange to seal it up properly.

We are now installing a Mercruiser smart gauge and the dealer needs to attach a harness to the sending unit to patch the gauge into.  I'm not sure if they removed it from the tank for some reason, but after they were done, they put the boat in the yard, and it started leaking again.

Is it normal for these units to leak like that and requir a sealant at the flange, or is there a problem with the sending unit seal? 

By the way I have a Rinker 260 EC.

Thanks. Mark.

Black_Diamond

No sealant = leak.  Should be a gasket at minimum at the flange, thread sealant certified for use with gasoline (pink PTFE tape).

MarkB

Thanks Black Diamond.

So the thread sealant is wrap around each of the 5 or 6 screws that secure the sender to the flange?

Black_Diamond

Yup, use the pink tape, it's made for gas/oil. Just wrap around the threads.