Hose as a fuel level gauge ?

Baggy

Baggy

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I dont have a fuel level gauge on my diesel tank, usualy measure by using a wooden dip stick. messy buisness !!

I,am having new inlet pipes fitted to the top and bottom of tank. for a fuel polishing system

Will it be ok to tee of these with stopcocks, (ie in parallel with the pump and filter ), and add a clear hose to check my fuel level ?

Diesel tank is situated about 2 feet from the engine
 
Clear plastic hoses can become stained over time such that they are nearly useless to see the fuel level. There is also the possibility that the hose would melt in a fire, compared to fire resistant fuel lines.

Perhaps there is suitable clear hose for this purpose. However, calculating the volume consumed based on time is a reliable method.
 
I agree with the comment that hose will become stained: the proper way to go is a glass tube, but then this has to be properly protected, and I hate to think what your Elfin Safety Nazis would do if they heard that you had a regular sight-glass!
+1 for the idea of reverse-engineering your cunsumption figures: I spent three happy years and about 15000 miles as an instructor and never ran out of fuel once!
 
My boat was rigged like that when I bought it and the surveyor pointed out the fire risk. Of course, the insurers jumped on it! To rectify the problem, I blanked off the top fitting and fitted a valve at the base of the tank. I took a solid pipe from the valve to a sight guage as used on domestic oil tanks, with a press to open valve incorporated in it. In the event of a fire, only the volume of fuel in the sight tube would be spilt.

The sight tube was bought from BES.

Another installation on a similar boat went to a stand pipe with an electrical guage fitted in it. Just like the sight tube, you have to provide a breather from the top to a point substantially above the heeled waterline.

Rob.
 
It'll be fine - the hose will discolour over a period of time - I'd guess 20 years! If you were to replace the hose every few years it would be very cheap - how much does less than a metre of suitable hose cost? It is a cheap and reliable solution.
 
Calculating by time is all well and good, but there's nothing like a gauge for reassurance when you're mid-Channel in a calm!

It will also only work well if you always motor at the same revs, which may not be true if your motoring consists of both longer legs in calms and short bursts in and out of marinas.

Pete
 
The nylon hose used for hydraulics and high pressure air seems to survive quite well. My central heating oil tank used it for 20 years and was still reasonably translucent. The replacement one used a little plastic ball float to make the level more visible. Unfortunately the tank split after a few years, so no long term test results on the plastic ball.
 
If you are using the same points for your fuel polisher then remember to turn off the polisher before reading the sight gauge. If the sight tube has a breather then the polisher may draw air from that rather than suck fuel from the bottom fitting especially when the tank is nearly empty. :)

In the absence of any clear tube connect a piece of any convenient hose to the bottom fitting, open the tap and gently lower the end of the hose down the side of the tank. When the fuel tops the pipe you have your level :)
 
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Tanks for all your comments.. see what I did there :)

The new inlet at the bottom of the tank will have a bronze tee fitted, The left side will go to the polishing pump via a stopcock, and the right side will also have a stopcock fitted, which will be connected to the hose and maybe drain tap as well, cos I dont have one on the tank at the mo..

It will be in the off postion most of the time, so changing the hose or clearing of diesel would be simplicity itself

cheers dab
 
PeteCooper said:
It'll be fine - the hose will discolour over a period of time - I'd guess 20 years! If you were to replace the hose every few years it would be very cheap - how much does less than a metre of suitable hose cost? It is a cheap and reliable solution.
Click to expand...

I have exactly that on my boat, 25 yrs old and the hose is still clear enough to easily see the fuel level. I also have shut off valves top and bottom so it can be easily isolated so no fire risk.
 
prv said:
Calculating by time is all well and good, but there's nothing like a gauge for reassurance when you're mid-Channel in a calm!

It will also only work well if you always motor at the same revs, which may not be true if your motoring consists of both longer legs in calms and short bursts in and out of marinas.

Pete
Click to expand...

Pete, I beg to differ. My calculations take into account a wide range of boat use, but mostly sailing at cruising (motoring) speeds. Most skippers don't spend hours at WOT, either. My spreadsheet has over 12 years of records.

OTOH, many fuel tanks are non-rectangular, and if they are narrower at the bottom than the top, the fuel gauge WILL be misleading.

Besides, who run their tanks to complete empty anyway? That requires bleeding the engine, which a lot of people either don't like or don't know how to do, although for most diesel engines it's very easy to do if you learn how.

For me, 20 hours, 10 gallons. Not so hard...:)
 
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