Replacement fuel tank level sensors

LaRea

If anybody has replaced or upgraded their fuel tank level sensors, what sensors did you use?

I'm on a long-term quest to upgrade my boat's instrumentation.  I already have access to the Smartcraft engine data via two MercMonitors, so I can see my fuel burn rates.  If I had tank level sensors on my network, the system could compute my range (miles to empty).  That would be very handy to have.  

However, my existing tank sensors aren't linked into the SmartCraft engine network.  And even if they were, they apparently only read to the nearest 1/8 of a tank.  That means my estimate of remaining fuel could be wrong by as much as 30 gallons at any given time.  For example, if I'm down to 35 gallons of fuel and the gauges are still telling me 60, that's very misleading.  Eventually, I want better tank sensors that connect directly to the engine harness and give me true analog measurements of the fuel levels.  

Now, do I really *need* better tank sensors?  Well, no.  I guess I could invent a scenario where better sensors would contribute to safety, but really I just like having lots of toys to play with.

Dream_Inn

Yeah, I'd love to hook up the fuel tanks to my Smartcraft as well.  Other item is the generator.  It'd be neat to have that connected, then you'd have fuel burn from it as well as some other diagnostics.  That looks like it might be as simple as another cable.

Handymans342

LaRea, do you really want to know fuel usage? LOL

LaRea

Hey, my boat burns a lot less diesel than yours!

Yeah, I'm looking at the genny too.  There's a SmartCraft adapter cable that plugs into genny accessory cable.  I just have to figure out the rest of the cable path.

Each engine harness has a connector marked "Paddle/fuel" that apparently can take up to two tank sensors.  I think they are set up for conventional resistive sensors, so I'm just wondering if anybody else has done it.    

Dream_Inn

I know Patrick (fmba on here) did it with his 400, but not sure of the results.

MarkB

I had to change my fuel tank sending unit to patch it into the smart craft system. My mechanic installed it over 2 years ago, so I'm not sure what he used. I'm going to be at the boat tonight, will I find any evidence of a model brand or number on the top of the sender?

LaRea

If you can take a look and tell me any identifying marks, I'd appreciate it.  

MarkB

LaRae, the only thing I can see on the fuel sending unit is "WEMA". Other than that, I can't find any other markings.

Stodge

See this is where I'm confused.  The multi-function gauge that includes fuel appears to be smartcraft.  There is a single plug that feeds it.  But it's not connected to the harness feeding my VesselView.  Looking for a way to bridge them over.

LaRea

Wema?  Well, that establishes the brand, so that's helpful.  Their sensors read in 0.5" increments.  I'm guessing the standard sensor reads in 2" increments, so it would be a big improvement.

Stodge -- On my boat, it's all standard Faria analog gauges, no SmartCraft.  

Stodge

I was surprised to see the plugs.  The VesselView harness has inputs for the tank info.  Like I say, not sure if/how to bridge from the existing connection to my VV.

MarkB

When my mech put in my Smart Craft system, he just plugged the NEW fuel sending unit (we had to order one that would interface with the Mercruiser system) into the harness. I also seem to remember, he needed a harness interface, probably to convert analog to digital. Anyhow, it's possible, and it isn't a big cost or a big deal to install. It all works on my boat - the only thing is I had to change my 4 in 1 Faria gauge as the fuel level didn't work with the new fuel sending unit. So I got the Smart Craft 4 in 1 gauge and piggy backed it to the System Tach gauge.

lightlarry

Hi Mark B
what part no did you use for the 4 in 1 gauge replacement
I have the smartcraft speedo and tach units in my 186br and fuel is connected but the faria 4 in 1 not does not work (fuel only everything else works) so would love to swap it out for a smartcraft 4 in 1
part no would be great need it in white with chrome bezel
thanks I am located down under in Australia
thanks for you assistance
Larry Kelly

MarkB

lightlarry - ooohhhh, I had to search high and low for that when I wanted to order. Even had to call mercury to confirm. I don't know why it isn't marketed better.

Download this pdf.

http://mercurymarine.co.za/files/brochures/8m0063378_2012gaugectlg_lr2_0.pdf

See page 6 has all the add on gauges (SC100 series).  Look for the 4 in 1. I believe it comes standard with a black bezel, so down at the bottom you can order other colors including chrome to match your other gauges.

lightlarry

Thanks Mark
exactly what I was looking for
cheers
larry