mercury smart craft fuel gauge

[WildFishExpeditions]

Hi all. I have had my new boat for just over 2 years now. from the beginning the fuel gauge on the smart craft didnt work or was not calibrated or whatever. Since I bought the boat from brisbane and i live in victoria, it wasnt going back to the dealer to get fixed. I also dont really care that much, as the gauge still tells me how much fuel I have burnt each day, and in real time - its just the standard fuel level page that doesn't work. at the initial 20 hour service the mechanic moved around some wires and said it should work now. it didnt solve the issue. So I was meaning to get it resolved at another service, but I forgot about it, and then forgot again on the most recent service. Next time I do get it serviced I will be sure to mention it to them, But what is the most likely problem? I have manually entered the fuel tank size into the smart craft gauge and I thought this world fix it. but still doesn't work.

again as I said, I dont really care, as I the page that shows liters burned is highly accurate anyway. But if anyone knows a quick fix that would be good.

[scottar]

So when you say "standard" fuel level display, are we to assume you have a resistive type sender unit in the tank that is hooked to the gauge? Which smartcraft gauge is it - there's a few different ones?

[WildFishExpeditions]

when i mean the "standard" fuel level, i am talking about the screen on the gauge that shows the tank is full to empty, I just didnt want this to be confused with the page which shows your burn rate etc. I guess I have a resistive type sender, i dont really know how else they work on a digital gauge. I dont know the exact model of gauge, i assume they are the SC100/1000 gauge, just from looking on the merc website. .

[scottar]

I will see if I can find a manual and have a look. There may not be a sender. Some modern fuel gauges rely on the user to program in the size of the tank and then how much fuel is in the tank as well as when fuel is added and how much is added. They then display fuel remaining by deducting the fuel used. If any one of these is not entered correctly, it will display incorrectly. I am not sure whether the Merc gauge operates this way or off a traditional sender. Someone with a Merc may chime in.

[scottar]

Just looking quickly, the Sc1000 gauge does have a calibration procedure for a resistive sender. You will need to empty your tank and run through this for starters at a guess. If you are familiar with using a multimeter it may also be worth checking the resistance on the sender wires at the back of the gauge (or wherever they connect - not sure) when the tank is at different levels. Think the Yaltas have a totally glassed in tank so access at the tank end may be an issue.

[WildFishExpeditions]

yes it definitely has a sender. My mechanic said he changed around some wires and it should now work, but it still doesnt. I have programmed it manually to add the size of the tank, so from the fuel burned it should be able to work out how much is in the tank, but i dunno how it measures the amount going in. well it doesnt anyway, as it doesnt work. i have read about emptying the tank and setting the calibration at 1/4 1/2 3/4 full etc. I guess i thought this sounded a bit caveman and surely there was another way to do it. maybe not.


I will see if I can find a manual and have a look. There may not be a sender. Some modern fuel gauges rely on the user to program in the size of the tank and then how much fuel is in the tank as well as when fuel is added and how much is added. They then display fuel remaining by deducting the fuel used. If any one of these is not entered correctly, it will display incorrectly. I am not sure whether the Merc gauge operates this way or off a traditional sender. Someone with a Merc may chime in.

[Noelm]

It doesn't "measure" the fuel going in when you fill up, you input the amount you added.

[Triple]

My smartcraft guages show whats in the tank from the level sensor and shows lph/range etc from im assuming the info from the ecu with injector pulses etc. Even when calibrating my level sensor slight variations in boat angle can change the remaining amount considerably. Stick with fuel used data if it correlates with what fuel your manually entering in each time.

[WildFishExpeditions]

I know currently it doesn't measure anything at the moment because it doesn't work. So how do I set it up so it works just like a normal fuel gauge? If you had to manually tell the gauge how much fuel you just added every time you filled it up then its not much of a "smart" gauge is it.


It doesn't "measure" the fuel going in when you fill up, you input the amount you added.

[WildFishExpeditions]

I think i have confused people. I am not manually entering any information. I manually entered the tank size, but that is all, I do not add the amount of fuel that i top up with every time I go to the fuel station, that would drive me insane. After I finish fishing I fill it up completely so i know I have 180L on board, then I reset the litres burned page so next time I am out it starts at 0.0L. I just want it to show whats in the tank from the level sensor, like yours does Triple. At the moment it is just permanently stuck on full.


My smartcraft guages show whats in the tank from the level sensor and shows lph/range etc from im assuming the info from the ecu with injector pulses etc. Even when calibrating my level sensor slight variations in boat angle can change the remaining amount considerably. Stick with fuel used data if it correlates with what fuel your manually entering in each time.

[bluefin59]

I think you will need to tell it how much you put in so it can calibrate the gauge to the tank but I maybe wrong ,I am sure one of the resident experts will explain it all . Matt

[WildFishExpeditions]

it says in the manual during installation to fill up 1/4, then calibrate, then fill to 1/2 then calibrate, then 3/4 then calibrate. But this isnt really an option now that the tank already has fuel in it. i guess I could run it down to 1/4 and try it, but I was hoping there would be an easier way!


I think you will need to tell it how much you put in so it can calibrate the gauge to the tank but I maybe wrong ,I am sure one of the resident experts will explain it all . Matt

[JulianDeMarchi]

Yes, each time you fuel up you have to tell it the tank is full or if you didn't fill it, how much you put in. The system won't register your tank is full from the sender.

[scottar]

I think the first thing you need to ascertain is that the sender is giving a varying resistance with different volumes of fuel. There could actually be a problem with the sender (sometimes they get stuck or simply just fail), the wiring, an incorrect sender type (there are two common types - some gauges allow for the sender type to be selected - not sure with smartcraft - check the manual) or it could simply be the calibration has never been done and until it is it wont work.

[JulianDeMarchi]

I think the first thing you need to ascertain is that the sender is giving a varying resistance with different volumes of fuel. There could actually be a problem with the sender (sometimes they get stuck or simply just fail), the wiring, an incorrect sender type (there are two common types - some gauges allow for the sender type to be selected - not sure with smartcraft - check the manual) or it could simply be the calibration has never been done and until it is it wont work.

I don't think he is talkimg about the sender Scott. My understanding is the tank level on the smartcraft is saying empty as the op has never told the unit it has a full tank.

[scottar]

I don't think he is talkimg about the sender Scott. My understanding is the tank level on the smartcraft is saying empty as the op has never told the unit it has a full tank.

Mentioned above(post 10) it is stuck on "full" - hard to diagnose stuff like this by remote control.

[WildFishExpeditions]

I'm not sure I understand what your are saying here.

there is no way in hell that every time you fuel up you have to tell the gauge how much fuel you put in. that would be the worst fuel gauge in the world.

the tank was never calibrated using the 1/4 1/2 3/4 method so it sounds like this needs to be done to get any results and there is no way around it. I dont think there is a problem with the sender, unless it was faulty from day one.

I have told the smart craft gauge that the tank capacity is 180L but I have never come across an option to say it is full or empty. the gauge just reads FULL all the time, and prior to the mechanic changing around some wires it just read EMPTY the whole time.

Am I missing something?


Yes, each time you fuel up you have to tell it the tank is full or if you didn't fill it, how much you put in. The system won't register your tank is full from the sender.

[JulianDeMarchi]

http://www.thehulltruth.com/boating-forum/423530-mercury-smartcraft-fuel-calibration.html

Seems I was mis understanding sorry. It does seem to go of the sender and the calabration might be your issue?

[mace01]

Definitely need the calibration. when I changed over to the new 115 CT, from the verado, I had to re-cal. Was bit of a pain...

The "telling the tank you've added X litres" works for keeping a tally in your HDS or other MFD connected via N2K

[bluefin59]

I remember reading on the HULL TRUTH about a calibration problem that turned out to be incorrect wiring on the sender , google is your friend . Matt

[Cape Crusader]

G'day
Not confident of my thoughts but seem to recall that when I had the smartcraft gauges I thought the info in the guages was all digital, generated by inputs of volume and use by fuel use monitor
The resitance sender was simply connected to a seperate analogue fuel gauge. They were 2005 version though
Our current suzuki ones have both connected to the gauges
Cheers
Rod

[NomadNoosa]

I have a 2016 510 Quintrex with 115hp Mercury and an underfloor 90 litre tank.
The fuel burn and tank level displays did not even come close to lining up. For instance I would be nearly empty and the Vesselview would show 60 litres left in the tank. That caused me a bit of grief as you can imagine.

The dealer pulled the sender out of the tank, and excuse my lack of terminology here, and the post that held the reader wasn't long enough to get to the bottom of the tank and the reader part seemed to be jamming as it got lower........anyway they replaced the whole part for a larger unit and it now reads within about 8 or 9 litres which I can live with.

Cheers

[Triple]

Should still work without calibration it just goes by the different ohm readings up and down on the float level. The calibration only sets it's parameters for different shaped tanks. If its reading full or empty all the time its a wiring or actual sender issue.

I tried recalibrating mine last time the tank was out and put in a new sender and it kept failing calibration half way through and was a pain draining fuel back out so just calibrated by taking it out and measuring tank depth and moving float up its corresponding 1/4 increments. Would only work on rectangular or square tanks but.


The info is separate data. The fuel tank level guage uses the resistive float sender to show you % left in tank. The smartcraft guages require you to manually enter how big your tank is and how much fuel you added or if you filled it for estimated range off fuel burn etc each time.

[WildFishExpeditions]

Ok thanks. I will try and get it sorted next time im at the workshop. The fuel burn computer is accurate to within about 3L out of 100L so thats good enough for me really.

[RayLamp]

I have a 2016 510 Quintrex with 115hp Mercury and an underfloor 90 litre tank.
The fuel burn and tank level displays did not even come close to lining up. For instance I would be nearly empty and the Vesselview would show 60 litres left in the tank. That caused me a bit of grief as you can imagine.

The dealer pulled the sender out of the tank, and excuse my lack of terminology here, and the post that held the reader wasn't long enough to get to the bottom of the tank and the reader part seemed to be jamming as it got lower........anyway they replaced the whole part for a larger unit and it now reads within about 8 or 9 litres which I can live with.

Cheers
This.

I'd be looking at the sender. The float inside the sender tube could be stuck, damaged etc. My boat had a new longer (and more accurate) sender which was also of higher quality than factory install. And it wasn't expensive.

[wags on the water]

Apart from the compass, are your gauges like this?.
115292
I used to have an issue when gauge was showing 0L left in tank, when in reality there was 30L - this was with a 180L tank. The pickup for the tank was in a position where you couldn't possibly use more than 150L. I found this out when I had the tank modified. The other issues I had 'understanding' the gauges was sorted by emailing Mercury Marine about the Smart craft gauges. Even though the AF brainstrust are a smart bunch of blokes.....you can't get better information than the people who work with them 24/7. My gauges are working well since the pickup was positioned in a point where there's only 5L left in the tank.

Cheers,
Wags