Temporary fuel flow gauge?

Expidia · May 8, 2009

Does anyone know if there is a type of fuel flow meter gauge that I could temporarily hook up.

And what or how does one hook up?

My dash only has room for two more gauges and I want to use one space for a fuel gauge and leave the other blank for some future use.

Once I've driven around awhile with a flow meter hooked up and know where I'm getting my most efficient performance vs fuel flow I don't really see the need of having to mount it permanently, since I would probably rarely look at it after that.

dingbat · May 8, 2009

Re: Temporary fuel flow gauge?

About the cheapest your going to find is the Lowrance LMF-200. It will give you fuel flow but you will have to manually calculate MPG. The Lowrance LMF-400 will calculate MPG if you connect it to a GPS but it's almost twice the price and requires a 3 3/8" diameter mounting hole.

The simplest method is to add a fuel flow sensor to your GPS if it supports one. I?m running a Garmin 4208 and installed the Garmin GFS-10 fuel management module. It gives me flow, MPG, usage, and if connected to your existing fuel level gauge gives tank a redundant fuel level indication as well. The cost of the add-on was less than $200

Mischief Managed · May 8, 2009

Re: Temporary fuel flow gauge?

The Lowrance LMF200 is perfect for your needs. It is not only a fuel flow meter, but is also a very accurate fuel gauge. You simply enter your tank size when you set it up and it displays fuel used or fuel remaining based on fuel flow, not the fuel sender in your tank (though you can add a sensor for that too, if you wish). It will also store your seasonal fuel use. You can spend $60 and add a paddle wheel speed sensor to get instantaneous MPG range and MPH data if you do not have an NMEA 2000 output on your GPS for this purpose (this is what I did). You can add other sensors to the LMF200 to measure oil pressure, coolant temp, and coolant pressure on your engine, and you can add sensors to measure air temperature, water temperature, and a host of other parameters. The installation is very easy and adding sensors in the future is child's play. I love the one I put on my boat last year.

Tacklewasher · May 8, 2009

Re: Temporary fuel flow gauge?

What have you got for a gps?

I've got a Lowrance 522 and hooked a fuel flow meter up. So I am just figuring out my sweet spot these days.

Silvertip · May 8, 2009

Re: Temporary fuel flow gauge?

It is counter productive to add the flow metering capability to establish some numbers and then remove the capability. Why? Because those numbers will change when another person steps into the boat or gets out of the boat. The numbers you initially gathered will only be valid on that day. Boat loading and water conditions greatly affect fuel consumption just like adding two, three, or four people to your car or towing a trailer with your truck. The real advantage of a fuel flow monitor is it can tell you instantly if you have an engine problem. If flow is typically 7 GPH (just to grab a number) with two aboard, a 17 foot boat with a 75 HP engine and flow rate is suddenly 9 GPH you had best head back to the dock as there is a fuel problem or the boat is very heavily loaded and you may need to recalculate fuel load to make sure you have enough for the trip. If you run big water you will very quickly get accustomed to using this tool very effectively. It is a very accurate fuel gauge, fuel used/trip, fuel used/total, fuel/remaining etc. And if MPG is more important to you then adding speed capability or interfacing with your other electronics gives you that capability.

Expidia · May 8, 2009

Re: Temporary fuel flow gauge?

Thanks for all these quick responses. I have a Humminbird 797C2I combo GPS.

The reason I asked this question was that two weeks ago I cruised down to a local restaurant on the Hudson River which it was a decent day chop wise and about 22 miles round trip. When I refueled I was surprised to see I only used a little over two gallons of my full 6.5 gal tank. Even though I was running wot at various times since it was more of a season opening shakedown run.

Two weeks later, on the same run (with my Wife on board) to the same restaurant and the round trip of 22 miles but this time going down I could only run at less than 10 mph because the waves were so high. I couldn't plane for most of the trip and was just plowing through the water.

On the way back it was a following sea so I was planing all the way back just cruising as it was such a nice day at around 20 mph. Just nice to be able to spend a day on the water and it was still only April.

I've made this same trip around a dozen times, but when I went to fill up I was down to fumes in the tank and it caughtt me by surprise because I was totally unaware. I have a 2.5 gal spare on board, but I'd hate to have to start filling the tank in a high wave situation with it even though it has a spring type valve spout, it's slow and it still drips around.

So being that I trailer around to different lakes and I don't really want to hang more weight off the transom by going to a 9 gal tank (the biggest that would fit in the fuel locker). I thought I might look into upgrading the tank to one that has a sending unit and install a fuel gauge in the dash. The flow meter would allow me to run at the most efficient speeds for weight on board and conditions.

I just figured after a awhile most conditions repeat them selves and by that time I would know what the most efficient variables were.

But I do like the idea of possibly adding a module to the GPS to gain flow info.
to the unit I have now. I paid $1,000 for it 2 years ago and I would think it has the option of adding it. I'll look at their website or call them.

And I always enjoy Silvertips concise informative posts on subjects like these. This site is great.

Tacklewasher · May 8, 2009