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David Ochs
05-24-2006, 04:39 PM
I'm fed up with fooling around with the fuel gauge in my old 16'.
It sits on 1/2 tank regardless of how much gas is in the tank.
So, what I'm thinking, is to go with a mechanical gauge. It's not a big deal to just open the floor plate and have a look to see what's left in the tank.
I have two questions:
1. Are the screw patterns on the top of the tank universal, will a replacement
line right up?
2. This manufacturer says that theirs won't work with a V bottom tank, as
my boat has? http://www.tempoproducts.com/2004/gauges.html
I figure it may not work perfectly, but it's better than what
I have now)
Any suggestions would be appreciated.
Thanks,
Dave

steven s
05-24-2006, 07:46 PM
I have an mechanical fuel hatch and it works great. Also make sure you cut in the right place:cussball: I say go for it!!!!

David Ochs
05-24-2006, 08:23 PM
Thanks, I don't need to cut anything. I already have an inspection port for access to the fuel shut-off and sending unit.

MOP
05-24-2006, 09:30 PM
The hole spacing on the fuel gauges has been a standard for many years, 4 in a perfect pattern two offset they only fit one way. The reason was to position the float correctly.

Phil

DickB
05-24-2006, 10:52 PM
I think the problem is with the swing-arm float design rather than with mechanical versus electrical. To keep the float from hitting the bottom or top of the tank, the swing is limited. As you fill the tank, the swing arm will rise, but it will stop moving well before the tank is full. Likewise as you empty the tank, it stops well short of empty. This explains why most gauges seem to stay stuck on "full” for so long.

My previous boat was a houseboat on the river. I wanted to be able to measure optimal speed for fuel consumption as well as have more precise full/empty readings. I installed a digital fuel flow meter. With it, you can get lots of information, such as consumption rate, gallons per trip, gallons consumed, and of course gallons remaining. Once calibrated (easy to do with just two fill ups), I found it to be very accurate to the fraction of a gallon, and it gave precise readings totally independent of tank shape, boat angle, etc.

David Ochs
05-24-2006, 11:28 PM
Dick,
I share your enthusiasm for the flow meter. What a terrific instrument to have! I contemplated the idea and decided against it since I would have to locate the sensor on the pressure side of the pump. That is without having to do a whole lot of work. I just thought this route would be quick and get the job done.
Which flow meter do you have, and is it on the vaccum or pressure side of the pump?
Phil, do you know if these flow sensors can tolerate being on the pressure side of the pump? If I could use it this way safely, I'll order one. What's a good one?
Thanks guys,
Dave

DickB
05-30-2006, 08:49 PM
I no longer have that boat, but I had mounted it before the pump. The installation manual is available online.
http://www.navman.com/upload/Marine/Internet_Manuals/2000/2100_fuel_MN000207A_eng_web.pdf
The only restriction cited is to mount it after the fuel filter, but I would try asking them your question.

BigGrizzly
05-30-2006, 09:08 PM
The flow meter must be on the suction sige of the pump.

David Ochs
05-30-2006, 10:59 PM
I emailed the "Faria" company about installing the flow sensor after the pump (pressurized side). They said that is not a problem. However it is important that it be mounted vertically and free of vibration.
I will though,reconfigure my fuel lines between pump and filter to have the sensor on the vacuum side of the pump. That sure seems safer to me too.
Thanks everyone, I'm anxious to get this in and try it out.
BTW, I have realized that installing a mechanical gauge was not feasible since the sending unit location is not directly under the access plate in the floor.