ECU/Fuel Tank Reading

[Barry Cohen]

When I turn the ignition key one click to the right, the ECU will initialize. When I push the white button that gives me the read-out for the fuel remaining, it is very accurate (based on last two fill-ups +/- 2 gallons). When I turn the ignition key one more click to the right and start the engine, the reading pegs to 100% and stays there. I come back to the slip, shut off the engine, repeat the process and I now have a new reading showing more consumption, as I would expect. Is this by design, or do you think we have an issue? I would much prefer to have an accurate/semi-accurate reading of fuel remaining while under way.

Thoughts? Anyone else experiencing this?

 

[knotflying]

Barry,
I have been using the Garmin for my fuel information rather than the Yanmar display. I found that when underway the fuel reading is way off because of the pitch of the boat. The Garmin will calculate fuel burned and deduct it from your filled setting. The thing you must remember though is that whenever you refuel you need to set the Garmin with the total fuel in the tank. So if you fill up you would set it to 99 gallons and if you refuel and do not fill it up you need to reset the amount in the tank to equal what was remaining before you fueled plus what you added.

Hope this helps,
Mike

 

[Barry Cohen]

I will give that a shot.

I have not been sure what the relationship is between the Garmin guage and the Teleflex gauge. It sounds like you are suggesting they are independent of each other.

 

[knotflying]

I believe they are. I think the Yanmar works on a float in the tank and the Garmin calculates based on fuel flow. Therefore when you are under way the fuel is sloshing around and depending on the pitch of the boat you will get different readings. I also fly a plane and I alway put my bet on the fuel flow calculation on my engine analyzer via the Garmin rather than the float guages and as you can see I am still here to report on the accuracy of the fuel flow calculation.

 

[Andrew Custis]

This is 100% correct and something I suggest to every owner that I do an orientation with. Any sender type gauge can create problems and having the engines coming wired via NMEA 2000 it talks to the Garmin which does the calculations for you. I know there is a thread on this but I will go through it again of how I would set up the gauge to make sure you get it accurate.

With the Garmin unit on and at the home screen.
1. Go to configure
2. Go to my boat.
Ensure that your fuel tank size settings are correct. Ranger R27 = 100 gallon fuel tank. Ranger R29 = 120 gallon main and Ranger R25SC = 80 gallon fuel tank.

Once those steps are done and your tank size is configured correctly, follow these next steps.

1. Fill up the fuel tank completely full. I use a "no spill" bottle on the vent to make sure I dont spill any fuel on this first fill up. These no spill bottles suction cup over the vent fitting next to the fill. The fuel usually comes out of the vent before it comes out of the fill but be careful. I only do this on the first time to ensure I had a full tank and the calculations will always be on the positive side.

2. From the Garmin Home screen with the engine key in the "on" position.
3. Go to information
4. Engines
5. Hit menu in the upper right hand corner.
6. hit fill up all tanks which will reset your fuel to the maximum capacity. This will set it to the tank size you configured in the first two steps of this post.

You can then create a combination by going to the combination tab on the home screen and using one of the lower two tabs in the combination screen. This will allow you to put engine information, gps, depth ect.... on the right hand of the screen by touching the black portion and inputting the information you wish to display. I usually add the following to my display in the right hand column. Remember if you are playing with this at the dock and not running the engine, the key to the ignition must be in the "on" position for it to display anything to do with the engine.

GPS heading
Depth
Speed
Fuel remaining
Oil pressure
Engine temp
RPM

Once this page is created or changed, it will save all of your setup for the next time use. When refilling your boat with fuel, you must do this everytime.

From the Garmin Home Screen with ignition turned on:

1. Information
2. Engines
3. Menu in top right corner.
4. Add fuel to boat and enter the number of gallons you have added.

This may seem like alot of work but always remember that this is a great way to track your fuel by using a much more accurate system other than the fuel tank sender that reads on the Yanmar gauge. This can all be done in less than 1 minute once you get it down.

 

[Barry Cohen]

Thanks Andrew. This will be done this weekend. I will keep these instructions with my manuals.

 

[JohnH]

I add my thanks to Andrew for his detailed explanation. I am purchasing but have not yet received a new R27, with generator. I believe that the generator shares the fuel tank with the engine(?). If so, I assume that the generator's fuel consumption is unknown to the Garmin and not included in the "fuel remaining" calculation displayed. What is the fuel consumption by the generator?

I presently own an R21, in which the fuel level is clearly visible (and there is also a conventional sender/gauge). Is there any way to view directly the fuel level on the R27? It looks like the tank is below the cabin sole at the aft end of the cabin. It would be reassuring to have a direct fuel measurement in addition to the calculation, since errors in the calculation will accumulate with each fill-up unless one goes through the entire calibration periodically.

-- John H