Fuel Tank Gauges on Hunter 410

[JohnEh]

I recently acquired a 2000 Hunter 410. There is a fuel gauge located at the helm by the tachometer. Before topping off the fuel tank with diesel, the gauge read about half full. After it was topped off, it read full.
There is another fuel tank gauge located in the cabin with the WEMA water tank monitors. There is a selector to monitor that gauge. I presume all of this came for the factory. If, all of this came from the factory, were both fuel tank gauges operational?

 

[sail sfbay]

.........If, all of this came from the factory, were both fuel tank gauges operational?

Expect so. Hopefully both gauges read closely the same. I have a fuel gauge in the cockpit of my relatively new 2005 Hunter 46 (first sailboat with a fuel level gauge) and it works.

 

[JamesG161]

If, all of this came from the factory, were both fuel tank gauges operational?

Mine were,
but...
The old version of the Wema had the "float" eventually get soaked and did not float correctly.

I replaced with the newest version for <$100 and reads perfectly and I can even calibrate my diesel tank to the nearest 2 gallons in a 50 gallon tank. Their float is now sealed and cannot get "soaked".

Here is the link to their sensors
SSS/SSL Sender – SAE 5 Hole Pattern Mount – KUS USA
Jim...

 

[JamesG161]

There is another fuel tank gauge located in the cabin with the WEMA water tank monitors

I have the same set up.
There is only one sensor.

You can have an exclusive Gauge, [used on many power boats]
and
The selectable Wema gauge panel for all the Wema gauges aboard.

Both get the signal from a single Wema diesel tank Sender.
Jim...

PS: The Helm gauge is a good idea to watch your fill.

 

[Don Lucas]

My 2001 410 only has the WEMA fuel gauge at the nav desk

Is is also the only level that still works

 

[JamesG161]

Is is also the only level that still works

I upgraded my Wema sensors on all tanks and now my Wema tank monitor works on all water tanks, Hold tanks and fuel
with the selector switch.
Jim...

 

[Nachismo]

Anybody had the gauge in the cockpit die? Mine always reads full in my 2008 H41DS when it should be down to 5/8 or 3/4 by now.

Or maybe these Hunters give a delayed reading? I swapped the sender & noticed the level is very high up front where the sender mounts. With a flashlight I can see the aft level thru the tapered part of the tank looks accurately depleted.

Hoping someone will tell me these gauges don’t show until half is gone or something. Otherwise I’ll just be motoring to burn fuel & see (and wishing I was sailing).
Also, I saw the gauge flip from full to 3/4 a couple times when a big wake rocked me. Seemed more like a loose wire than a slosh but I find no loose connections (tore apart gauge in cockpit & replaced WEMA Multi).

 

[smokey73]

It is generally a good idea to keep an accurate log of engine hours, generator hours (if you have one) to calculate the fuel usage. It is a bit difficult to allocate between what the generator uses and the engine uses but after awhile you'll get a good estimate. I use 1/2 gal per hour as my estimate for the generator and then the rest of the fuel usage is allocated to the engine. From that you can get a "handle" of how much fuel you should have used between fillups. From that I can estimate how much fuel I will need to pump and compare it to how much I actually had to pump.

Then I record the tank level just before I start refueling and the total gallons pumped to fill the tank. I have found that my fuel gauge reads conservatively (ie when it says 1/2 full it actually has a few gallons more in it). Also, since my tank is not square with it wider at the top, it takes awhile for it to go from full to a reading below full (much like my car does.)

Getting to know what your expected fuel usage is and how your guage reads with respect to how empty it really is will be useful. When I installed my new fuel tank, I added fuel from cans 5 gallons at a time and recorded the reading. The guage was reasonably accurate, considering the odd tank shape and conservative at all readings. Just my 2 cents.

 

[jssailem]

@smokey73 is spot on. It is a bit old school but it is how Mariners have managed fuel since the invention of steam powered boats.

You start from full. You motor for “X” number of hours. You record the hours and sea conditions. You fill the tank getting a measure of how much you put into the tank.

You now can calculate how much you burn per hour. You can use the sea conditions time to help refine the consumption estimates.

Keeping a log over time will give you an accurate rate. If in addition you look at the tank and take a physical volume estimate you can then compare the information with the idiot gauges in the cockpit to get a understanding of their representation fuel available.

 

[Nachismo]

Yeah that’s how I know my gauge should be reading btw 5/8 & 3/4. I just like it when stuff eorks

 

[Nachismo]

*works

 

[jssailem]

We all like our stuff to work as expected.

On my boat I want my gauges to work. I use them. I just validate that what they are tell me is factual data. I know that when my fuel gauge says “your empty” it means I’m into my 3 gallon reserve. I have another 26nm of range. I set it up that way when I installed sensor.

 

[smokey73]

Mine is about a 5 gal reserve to allow for sloshing around.