how much fuel do you have when guage hits red.

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atlowers

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My tank holds 218 litres, filled up at the weekend when guage showed start of reserve with 134litres indicating 84 litres in reserve. Seems high to me at 38.5% capacity as guage indicates 1/4 tank only left.
What do you have in reserve when guage hits the red line?
Wondering abut my guage accuracy.
 
Depends on the type and setting of the sender on most boats and there is rarely a definitive answer unless you actually remove the sender and offer it up to the side of the tank to check its travel,full position and empty position.
 
I've never let my tanks go into the red. Full tank before every trip and fill it up when I return. Best practise. Less chance of picking up sh1te from the bottom of the tank, and less chance of water build up from condensation
 
Open hatch >>> look into dark hole >>>click on fag lighter to see fuel >>> fuel present >>> get superb view of your boat from approx 300' altitude >>> note to ones self, fix fuel gauge...
 
>>> Open hatch
>>> look into dark hole
>>> click on fag lighter to see fuel
>>> fuel present
>>> hear "whoosh" then watch what appears to be a burning scarecrow achieving altitude of approx 300'
>>> think "huh?" as you look down, your hands are grey and poorly defined, you reach for the hatch, and your arms go straight through it...
 
Re: how much fuel do you have when gauge hits red.

I ignore my gauge and I will try to explain.

Your tank is an odd shape but ends in a V, when half level you have very little usable fuel left.

Fuel in boats can be dirty as many boats don't get used much, if this dirt is picked up then your engine could stop.



I presume your falcon is petrol so you should be less affected by dirty fuel but if you let the tank go more than 30% empty you risk the chance of stirring muck up, especially if it is rough.

As a result I try to keep my tanks at least half full ( an I regularly drain the bottom few gallons out just to check and be on the safe side).

I also took on board your estimate of remaining fuel but on small sports boats a full tank may not actually be full.

Because it is laid flat ( I guess under your bed) if you stand on the side as you fill it then the pump will cut off at 3/4 full.

you can test this by seeing how much extra fuel you can get in with a funnel and jerry can, just because fuel comes out the breather does not mean your tank is full.

Best way is to ignore your gauge.
Calculate how many MPG you get.
Then deduct MPG from the miles you have covered since your last top up.

I don't totally ignore the gauge , I do keep an eye on it for added safety

I once took a small petrol boat 110nm to Le Harve, I needed a full tank, so I got 3 people to stand on the bow so I could get an extra 12 gallons in.
 
When the needle says it's full, it means its actually somewhere between 100% and 85%.

When the needle says it's half full, it means its actually somewhere between 35% and 25%.

When the needle says it's one quarter full, it means its actually somewhere between 10% and 5%.

I found this out the hard way........but did not actually run out. I just knew from the amount that it took when filling up how close to empty I had got! /forums/images/graemlins/blush.gif /forums/images/graemlins/blush.gif /forums/images/graemlins/shocked.gif /forums/images/graemlins/shocked.gif
 
On the S28, it's not exactly linear. Tank is 400L:

Full, gauge stays hard over to the right for the first 50 litres.
Then goes whizzing down to the half way mark, which is about 200L left.
The red zone starts at about 100L left, which isn't far off.

I have no idea how accurate the gauge is within the red zone, nor do I intend to find out! I get very twitchy with anything less than half a tank onboard.

dv.
 
Hi my tank holds 454ltr when the gauge reaches 0/reserve i have aprox 135ltrs in reserve, each segment of my gauge equates to aprox76.5ltrs,if set up properly they should be quite acurate,my boat is a fairline by the way regards m m 1.
 
[ QUOTE ]
Anybody who believes their boat's fuel gauge is living in Wonderland.

[/ QUOTE ]Unless you have sight gauges: waaaay more accurate and practical than lifting the hatch.
I agree that sender+needle gauges are useless, though.
 
Full Tank Manufactures Details 760L, Red Zone mark normally takes about 500L +/- depending on speed of pump to refuel . best guess on Red zone 250L+/-
 
Thanks for all the reply,s. I to very rarely let the tank get down to the red line following filter problems after a 105mile delivery trip when I first purchased the boat when the tank nearly emptied. That was the point of ny post in that running the tank down to the red (ignoring guage accuracy) effectively leaves the tank roughly a 1/3 rd full so
a)why do I worry so about topping up at half full/empty.
b)Thinking about a trip in my little falcon across to the channel islands, depending on conditions, that red bit could be quite important. (common sense planning and margins should make this n/a but I do like a big safety margin)

ps its a diesel not petrol.
 
As timtap says, it depends on how the sender is located. On my boat (and many I suspect) the sender is mounted so its bottom position is 6 inches above bottom of tank so I can and do let it go way into the red. you need to figure out how yours is configured. Also a tapered/irregular shaped tank will give you a non linear readout on the guage, obviously

I dont agree at all with this stuff about sh!te in the bottom of ther tank. The pick up tube is at the bottom of the tank anyway, so it's ALWAYS the bottom fuel that is being taken by the engine. And there are zillions of filters twixt tank and engine to catch any bits of crud. So that's all cobblers imho.
 
Muck in bottom of tank.



A half full tank will not stir up muck at the bottom even when rough.

A near empty tank will not cause a problem if it is smooth.
But if you have a near empty tank 10%-30% and you bounce the contents around you will stir it up and soon clog your filters up.

Note how the contents of a full 2 L coke bottle react when shaken compared with one with an inch in the bottom.

The tank has baffles in it and muck will sit behind the baffles undisturbed for years, once the tank nears empty there will be fuel washing around the crevices to clean out all the corners and send it to clog your filters.


This happened to me with the last boat, forced to carry on to my next fuel stop near empty (17%) and rough off North Foreland, I managed to reach fuel and fill up only to have to change filters after 60 nm.


Sorry atlowers for suggesting your boat was Petrol /forums/images/graemlins/blush.gif

reason for fuel shortage here but long read
 
I tend to agree with that. I've got a sight guage on my tank which goes to the bottom of the tank and there's no obvious signs of crud at the bottom of the guage which suggests that there's no obvious crud at the bottom of the tank and, as you say, there are coarse and fine filters which are supposed to take care of that stuff.
I often run with an almost empty tank because the thing goes a bit faster
 
In a new or nearly new boat that is fine but the posters boat is a Falcon 23 getting on for 15- 20 years ?

It could have had a new tank, it could have had a diligent owner that has drained and cleaned the tank but there is a good chance there is 15-20 years of crud in the bottom, the baffles prevent a suction hose from getting to the corners to clean it out.

Not sure where your viewing point is but there could be a low point where water/crud settles which you can not see.


I agree there is a good argument for deliberately running low in order to keep the tank clean on a new tank, but this would be asking for troubles on an older tank.

All in my opinion of course, I could be wrong.
 
My own experience was that when I purchased the boat, it had been used for very short trips only and ad always had a pretty much full tank maintained. We picked it up from west bay and she ran sweet til mid solent when we were reduced to 6knots. Reason- filters blocked with aforementioned shite. We subsequently had to chang the filters some 3 times in quick succession so it wood indicate that a lot of crud had been disturbed by the long trip home and the near emptying of the tank. (Not an easy tank to empty and clean as access is limited to say the least.)
 
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