New Fuel Sending Unit

[FourPoints]

After nearly 36 years the sending unit on my fuel tank has decided to stop working. On a previous boat I had installed a WEMA sending unit as they were quite well regarded at the time. Now a decade later I see lots of off brand options that appear to "borrow" that design listed online, and I'd like to get suggestions on what the current line of thinking is for quality (diesel) sending units. Tank is poly, 13 inches deep & pretty close to a simple rectangle shape.

I also saw Moeller sells a sensor similar to the WEMA S5 called a Reed, but they say they need 1" clearance above the bottom of the tank, but only come in 11 or 13 inch depths, so I'd be left with 0 or 2 inches below the sensor. Upside is that I can get it in 1-2 days compared to the WEMA which I think it has to ship from the UK.

So, what's everyone's current favorite in reliable fuel sending units?

 

[FourPoints]

Just noticed that what used to be WEMA's US branch split off is now KUS USA, so should presumably be similar quality to what I used on the old boat? SSS/SSL Sender - SAE 5 Hole Pattern Mount Level Sender | KUS Americas, Inc. (kus-usa.com)

Thoughts?

 

[Dave]

Just noticed that what used to be WEMA's US branch split off is now KUS USA, so should presumably be similar quality to what I used on the old boat? SSS/SSL Sender - SAE 5 Hole Pattern Mount Level Sender | KUS Americas, Inc. (kus-usa.com)

Thoughts?

Yes. Wema is now Kuss.

The shorter length provides for a reserve fuel supply.

 

[Rich Stidger]

After replacing the float on an arm type of sender a couple times, I tried the KUS rod-type sender. I'm not sure if it was that exact brand, but it was that style. So far its been 3 years and it works flawlessly.
Regarding your clearance to the bottom of the tank- Did you actually measure the tank or are you going from published specs? Given that the pickup tube is probably 1/2" off the bottom, having a 1/2" clearance is probably a good idea.
If you can't get the exact length you need, how about cutting a spacer out of starboard or some fuel impregnable material and placing it between the tank and the sender, thereby lifting the sensor off the tank bottom? Obviously you need gaskets between the sensor and the spacer and between the spacer and the tank, and some longer screws.

 

[Ralph Johnstone]

how about cutting a spacer out of starboard or some fuel impregnable material and placing it between the tank and the sender, thereby lifting the sensor off the tank bottom? Obviously you need gaskets between the sensor and the spacer and between the spacer and the tank, and some longer screws.

Brilliant use of Starboard as it's impervious. Rather than a solid gasket, I have found Permatex the only sealant that sticks to poly like to a blanket:

Nothing else will stick to poly.

 

[Rich Stidger]

Rather than a solid gasket, I have found Permatex the only sealant that sticks to poly like to a blanket:

Good to know.. Thanks for the tip.