Been having trouble with fuel gauge. Often it reads full when I know tank is not full. To remedy I've started using the fuel used and total fuel remaining gauges on the glass cockpit. To check accuracy I marked level on fuel tank added 15 gallons of gas. When fuel used gauge read 15 gallons I rechecked tank and level was just about on mark. Seems pretty accurate. Now when I add gas, i just enter amount into the glass cockpit.
Anybody else using thise gauges?
2021 R5 fuel gauge
Re: 2021 R5 fuel gauge
What engine make do you have. The VP's have two calibration processes you do at the EVC. I did the Full Fuel Calibration (the simplest) and it is fairly accurate.
2021 R5 Shale/Ebony
VP 5.3L 350
"$TSLA"
VP 5.3L 350
"$TSLA"
Re: 2021 R5 fuel gauge
On our R5 with a Mercruiser, it reads full for a long time. Based on fuel used, it is pretty accurate when around half full. As the tank empties, the gauge appears lower than it really is.
I go by fuel remaining. It seems VERY accurate.
I go by fuel remaining. It seems VERY accurate.
2017 R5 350HP Mercruiser Bravo III
Northridge, CA
Big Bear Lake, CA
South Lake Tahoe, CA
Northridge, CA
Big Bear Lake, CA
South Lake Tahoe, CA
Re: 2021 R5 fuel gauge
You can correct the inaccuracy by adding a resistor to the sender circuit. The sender typically has a resistance of 30 ohms at full and 240 at empty, for a range of 210 ohms. If the gauge is reporting 10% too high, theoretically you would add 21 ohms. Try adding 15 and see if you like the results. If it is reporting too low, you have to add a resistor in parallel and the math is a little more complicated.
Re: 2021 R5 fuel gauge
You can correct the inaccuracy by adding a resistor to the sender circuit. The sender typically has a resistance of 30 ohms at full and 240 at empty, for a range of 210 ohms. If the gauge is reporting 10% too high, theoretically you would add 21 ohms. Try adding 15 and see if you like the results. If it is reporting too low, you have to add a resistor in parallel and the math is a little more complicated.
- Krob1114
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Re: 2021 R5 fuel gauge
I didn't notice the remaining fuel option on our Garmins. We're making a trip to the lake in a few hours, and I'll check.
2019 Cobalt R3 @ Greers Ferry Lake, AR
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