Fuel sending unit replacement

[DBreskin]

I thought my boat had been getting poor mileage but I figured out my fuel gauge is inaccurate. When the gauge starts bouncing on E there's still 1/3 to 1/2 left in the tank. Today I removed the original equipment sending unit with the hope I could adjust/bend the float rod and get a more accurate reading. I discovered that at full down swing the float is still well off the bottom of the tank. You can see in the picture the sending unit is relatively short for a 12" deep tank. There's no adjustment to be had on this unit.

If I replace the sending unit with a 12"-24" adjustable unit, will I be able to get better results? Please comment and criticize.

 

[1ArmBandit]

Re: Fuel sending unit replacement

id say yes

 

[jdlough]

Re: Fuel sending unit replacement

I replaced mine with this, built by WEMAUSA

http://www.iboats.com/Moeller-Reed-...8928815--session_id.976592214--view_id.368241

It's stainless steel, so no corrosion. It's not adjustable, and you need to know the exact tank depth. Iboats sells a few different sizes. If you need another size, WEMAUSA has them in 1/2" increments. I replaced my sender with this one. The gauge doesn't bounce around so much anymore.

An even higher tech version is this one

http://www.iboats.com/Teleflex-Soli...8928815--session_id.976592214--view_id.886253

No moving parts, and you can adjust it to length. I think it's also made by WEMA.

 

[JoLin]

Re: Fuel sending unit replacement

I'd also suggest the type jdlough mentioned above. I just went through this with a too-short sender. When I replaced it with a longer swing-arm type, I discovered there's a baffle inside the tank that the longer arm 'hung' on, perventing it from swinging. I just got a call this afternoon that my new 'reed' sender is in, so I'll be replacing it tomorrow.

 

[Chris1956]

Re: Fuel sending unit replacement

DB, Fuel gauges can be wildly inaccurate. Experience suggests replacing the sender may or may not make it more accurate. You might try it, but prepare yourself for the gauge to act differently, and not more accurately. I have learned that when my speedboat (9" flat tank) gauge first reads empty, it had 1/3 of a tank remaining. A new tank and new sender with the tank did not change that reading.

 

[UncleWillie]

Re: Fuel sending unit replacement

Unless the sender is physically mounted in the center of the tank, Bow up and bow down can make the gage read full or empty.

It sounds like your sender is at the front of the tank. With the bow up while underway the fuel sender will report less fuel than actual because all the fuel is in the back of the tank.

There is nothing wrong with a sender that is pessimistic.
It's better to go home with a 1/3 tank than run dry thinking you still have a 1/3 tank.

The sender on mine is in the rear of the tank.
I can run for 3 hours before the needle comes off of full.
At that point I am just a little over half full.
Judge your mileage by how much it takes to fill up again, not by the fuel gage!