# Is a manual gas gauge possible with any fuel fill valve?



## dbs1515 (Aug 21, 2013)

I am not near my skiff at the moment as I am lucky to still be working outside of my home, but I have a question for you folks out there in the skiff world....

I see the value in a manual gauge as we all know how relatively inaccurate an electronic gauge can be. I was imagining how nice it would be to have a very accurate way of checking my fuel when I am out on a 2-3 day trip, making long runs each day. We all see this on the HB Skiffs, but I don't know that I have seen in on other brands of skiff so is this only possible with certain tanks/valve models? 

My last skiff (Ankona Native SUV) had the standard two-hole cap that you would use a specific key to open. Once opened the hole appeared to go all the way down unimpeded. My latest skiff, 2019 Mosquito, has a flip up/twist off valve cover and then a spring loaded flap several inches down. Is there a reason I should not attempt to make a wooden dowel-type device for this valve. I do not want to have anything break off in the tank or get damaged just to pursue something that isn't 100% necessary. I can post pics of the valve later, but in the meantime any brainstorming on this is always welcomed by the experts here who know quite a bit more than me. Thanks everyone.


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## jmrodandgun (Sep 20, 2013)

Why would a fuel gauge that reads resistance be any different than one with the needle hooked directly to the float? If anything I think the manual read would be less accurate.


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## dbs1515 (Aug 21, 2013)

Maybe I should have specified...more or less the gauge itself on the console is not as accurate or easy to calculate. It has a full, half and empty reading only. The reason I became curious is the console gauge read empty for the 15 gallon tank, yet when I went to fill it, it only took 11 gallons. If I had 4 gallons left in the tank, that would be nice to know if I wanted to push the limits of my tank every now and again.


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## lemaymiami (Feb 9, 2007)

I’m a guy who’s had bad results with fuel gauges so I tend to distrust them.. I much prefer a dipstick measuring system if possible (many larger fuel tanks are offset from where your fuel fill is so you can’t dip straight down to the bottom of your tank...). If you can use one -nothing is more accurate than a dipstick.

Here’s how I make mine... You can use any wood dowel -but I prefer to use a stick of teakwood if possible. I start with a 3/4” by 1/4” slat -about four inches longer than the total distance from the bottom of the tank to the top of your fuel fill. Sand it smooth and you’re ready for the next step. What you need is an empty tank to start with.. then it’s off to your gas station. Pump in the first five gallons (or six if you prefer) then dip that new stick and mark the fuel line with a knife or file, then add the next increment and make another mark - then keep repeating until the tank is filled... One part of the info that this will show you is exactly how much fuel your tank will hold (it will always be less than what’s claimed- sometimes a lot less...).
Now that you’ve made your marks, go back and with the edge of a file mark shallow grooves all the way across the stick so that each level is easily seen in almost any light. Very handy...

Two other things before you’re done... It’s smart to actually make two sticks when making one. Put the second one away as a spare... I like to attach a fuel key to the outside end of my dipsticks as well.

Hope this helps - aren’t boats fun?


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## Lowtidelowlife (Aug 19, 2014)

Flat skiff tanks are shallow. By the time your float starts reading a difference you’re already through half the tank. I have the garmin hooked into the mercury and it measure fuel burn and is insanely more accurate than anything else I’ve ever used. I have always used my “so I went this far at this speed and probably burned this much” method. And always use thing 1/3 to get there 1/3 to get back and 1/3 to evade authorities method of fuel estimation for a trip anyhow.


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## dbs1515 (Aug 21, 2013)

Thanks, Capt. I hope to be able to use one, and that it's possible for my tank.


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## dbs1515 (Aug 21, 2013)

I have the Suzuki 60, and the Simrad Go7, is there a similar interface like with your Merc, Low Tide?


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## Lowtidelowlife (Aug 19, 2014)

dbs1515 said:


> I have the Suzuki 60, and the Simrad Go7, is there a similar interface like with your Merc, Low Tide?


I don’t know about simrad. I know mercury is a pain in the ass to interface with nmea but I’m sure you can interface if it’s a modern outboard. I don’t even have a fuel gauge on my boat anymore.


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## Water Bound (Dec 12, 2018)

Yes you can, I recommend a search on The Hull Truth...lots of threads on the topic over there



dbs1515 said:


> I have the Suzuki 60, and the Simrad Go7, is there a similar interface like with your Merc, Low Tide?


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## lemaymiami (Feb 9, 2007)

Measuring the fuel in your tank is one thing... Learning about the amount of fuel your rig burns.. is a different matter entirely.. Here's a quick tutorial on how to be pretty certain about your fuel consumption... 

Most skiffs these days have a gps aboard.. With it you can know exactly what your motor burns in just a couple of trips.. First off every motor burns fuel differently at different speeds. The general rule is that you get you best "miles per gallon" at somewhere between 70 and 75% of your throttle... If your motor will run up to 6000rpms, then 70% would be 4200, 75% would be 4500rpms... Try your best when you're measuring fuel consumption to stay in that magic 70 to 75% range... Run hotter than 75% and watch your fuel burn go up... something every race driver knows all too well... 

You're going to start your day on the water with a full tank, period. Then you're going to find the trip log on your gps and set it back to zero (yes, most have never read their instruction manual and can't find their trip log - but it's there if you look...). Now do your day on the water - and try to stay within that 70 to 75% throttle range.. Then at the end of the day check that trip log and see how many miles you've covered and make a note of it before re-setting it back to zero again... All you need to do now is top off your tank on the way home and make a note of exactly how much gas you burned during the day... and you've got all you need... 

Divide miles run by gallons burned and you'll know exactly how much gas you burned... Repeat this two or three times and you'll have a very good idea of what your rig burns per mile run... Mine is so accurate (I'm burning one gallon every five miles - a 30 year old Maverick skiff with an E-tec 90 motor - a newer, lighter hull might get seven miles per gallon or better with that same motor...) that all I have to do is call up my trip log and I'll know to the gallon how much I've burned and how much remains... 

There are some added benefits to knowing this kind of info for each boat you run (whether you own it or not)... First off you should always top off your fuel tank at the end of each day on the water if possible... Half empty tanks invite moisture condensation, resulting in water in your fuel (bad scene...). Knowing your consumption will provide you an accurate basis for being precise about the range you can run on a given trip.. That old airplane adage about one third out , one third back, and one third of your fuel as a reserve... is right on the money and something very few actually know precisely... That same trip log info will allow you to know just how far it is to that secret spot (and it won't be hard figure out exactly how long it will take to get there... ).

Hope this helps and aren't boats fun?


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## Capnredfish (Feb 1, 2012)

I did similar to what Lemaymiami said. However I just marked my tank in 5 gallon increments. It holds 15. I can see through the plastic tanks to view level. Gauge on console has been accurate. And I run an Etec.


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## dbs1515 (Aug 21, 2013)

It all helps, thank you. Every time I read these forums and couple that info with on the water experience, I benefit tremendously. What starts as selfish motivation (trying to maximize gauge precision), turns into so many other lessons learned and a safer boating experience for me and everyone I bring along. I always appreciate even the smallest tips, reminders, tricks, adages etc... I know many of you learned this information from someone or have the ingenuity to figure it out. Just flattening my own curve some.


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## georgiadrifter (Jan 14, 2009)

Protip: for the dipstick users (I am one)....be consistent when using the dipstick. What I mean by this is...always measure with the boat in the same position. I usually measure while the boat is resting in my trailer and hitched to the truck. Measure while boat is on the water will give a different result.


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## jay.bush1434 (Dec 27, 2014)

dbs1515 said:


> I have the Suzuki 60, and the Simrad Go7, is there a similar interface like with your Merc, Low Tide?


You'll need a NMEA 2000 starter kit and you might as well buy the new Suzuki gateway. Your NMEA 2000 will plug into the back of your Simrad. The other end will obviously plug into the outboard. You can get a ton of info from your motor through your Simrad. I have my Zuke connected to my Lowrance HDS7 g2 touch. I read fuel burn at the injectors and it is very accurate. When I fill up, I reset the trip fuel used and then just look at the fuel used and subtract from tank capacity and I know just how much I have left. I have run my tank empty so I know that it will suck the tank dry and I can use all the fuel in the tank. I can usually tell the kid at the fuel dock how much fuel I'm going to add within half a gallon. All the inaccuracies are my rounding error. Since the fuel burn is connected to the GPS, I can also get instantaneous MPG so I can also do some quick math in my head and know what my "distance to empty" is. 
There is a long and very informative thread on The Hull Truth. It is a sticky so it is right at the top.


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## dbs1515 (Aug 21, 2013)

jay.bush1434 said:


> You'll need a NMEA 2000 starter kit and you might as well buy the new Suzuki gateway. Your NMEA 2000 will plug into the back of your Simrad. The other end will obviously plug into the outboard. You can get a ton of info from your motor through your Simrad. I have my Zuke connected to my Lowrance HDS7 g2 touch. I read fuel burn at the injectors and it is very accurate. When I fill up, I reset the trip fuel used and then just look at the fuel used and subtract from tank capacity and I know just how much I have left. I have run my tank empty so I know that it will suck the tank dry and I can use all the fuel in the tank. I can usually tell the kid at the fuel dock how much fuel I'm going to add within half a gallon. All the inaccuracies are my rounding error. Since the fuel burn is connected to the GPS, I can also get instantaneous MPG so I can also do some quick math in my head and know what my "distance to empty" is.
> There is a long and very informative thread on The Hull Truth. It is a sticky so it is right at the top.


Jay, thanks that is supremely helpful. Sounds like, with a small upgrade, I will have all the information I was looking for. I appreciate you taking the time to share!


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## Steve_Mevers (Feb 8, 2013)

dbs1515 said:


> Maybe I should have specified...more or less the gauge itself on the console is not as accurate or easy to calculate. It has a full, half and empty reading only. The reason I became curious is the console gauge read empty for the 15 gallon tank, yet when I went to fill it, it only took 11 gallons. If I had 4 gallons left in the tank, that would be nice to know if I wanted to push the limits of my tank every now and again.


I adjusted my sending unit in my tank so that when my gauge reads empty, it is really empty. It really doesn’t matter to me how accurate it reads on full, but when running out of Flamingo for several days having a gauge that reads accurately on empty is very important


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## Zika (Aug 6, 2015)

It's not possible on the BT Mosquito tank set-up. I specifically asked Will about it and he said another owner had tried to punch through the internal flap to use a dip stick. Didn't work, caused major damage and was an expensive repair. 

I usually keep my tank topped off before every trip. Helps with weight forward when fishing solo and I don't worry too much about gauge accuracy.


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## dbs1515 (Aug 21, 2013)

Zika said:


> It's not possible on the BT Mosquito tank set-up. I specifically asked Will about it and he said another owner had tried to punch through the internal flap to use a dip stick. Didn't work, caused major damage and was an expensive repair.
> 
> I usually keep my tank topped off before every trip. Helps with weight forward when fishing solo and I don't worry too much about gauge accuracy.


Thanks, Zika. That definitively answered my question about the tank. I'm certainly glad I asked you folks before doing something to cause damage. This is why I love Microskiff.com


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## dbs1515 (Aug 21, 2013)

Steve_Mevers said:


> I adjusted my sending unit in my tank so that when my gauge reads empty, it is really empty. It really doesn’t matter to me how accurate it reads on full, but when running out of Flamingo for several days having a gauge that reads accurately on empty is very important


Is this something anyone can do?


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## jmrodandgun (Sep 20, 2013)

dbs1515 said:


> Maybe I should have specified...more or less the gauge itself on the console is not as accurate or easy to calculate. It has a full, half and empty reading only. The reason I became curious is the console gauge read empty for the 15 gallon tank, yet when I went to fill it, it only took 11 gallons. If I had 4 gallons left in the tank, that would be nice to know if I wanted to push the limits of my tank every now and again.


You can adjust the float or switch over to a WEMA or solid state probe style sender. I have a solid state sender on my 15 gallon tank and it's very accurate.


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## jay.bush1434 (Dec 27, 2014)

Zika said:


> It's not possible on the BT Mosquito tank set-up. I specifically asked Will about it and he said another owner had tried to punch through the internal flap to use a dip stick. Didn't work, caused major damage and was an expensive repair.
> 
> I usually keep my tank topped off before every trip. Helps with weight forward when fishing solo and I don't worry too much about gauge accuracy.


@dbs1515 I have a similar fuel filler neck fitting and can't use a dip stick on my 2014 Vantage. I asked East Cape about it a couple years ago and it had to do with EPA regulation changes. They had to use that set up for about 6 months until newer compliant fittings on the tanks were available. I was adamant about not having that crappy set up on my new skiff build.
Incidentally, the NMEA 2k starter kit and Suzuki gateway is about $250-275-ish. The gateway allows engine diagnostic alarms and some other information to be displayed on your multifunction display.


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## dbs1515 (Aug 21, 2013)

jmrodandgun said:


> You can adjust the float or switch over to a WEMA or solid state probe style sender. I have a solid state sender on my 15 gallon tank and it's very accurate.


Thanks for that clarification


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## dbs1515 (Aug 21, 2013)

jay.bush1434 said:


> @dbs1515 I have a similar fuel filler neck fitting and can't use a dip stick on my 2014 Vantage. I asked East Cape about it a couple years ago and it had to do with EPA regulation changes. They had to use that set up for about 6 months until newer compliant fittings on the tanks were available. I was adamant about not having that crappy set up on my new skiff build.
> Incidentally, the NMEA 2k starter kit and Suzuki gateway is about $250-275-ish. The gateway allows engine diagnostic alarms and some other information to be displayed on your multifunction display.


Yeah, I can see the interface screen on the Simrad, it is just blank right now because it isn't hooked up. Once hooked up, I imagine that would be helpful to track hours and run diagnostics should anything start to have issues years down the road. Thanks again.


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## Steve_Mevers (Feb 8, 2013)

dbs1515 said:


> Is this something anyone can do?


I have a float style sending unit that is adjustable.


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