Fuel sight gauge

[MtB]

My diesel fuel day tank has a bit of problem... Two problems actually.

 

1) I've no idea how much diesel it contains as I fill it, until fuel squirts out of the vent hole in the top.

 

2) I've a feeling the vent hole in the top is supposed to be connected to outside by a tube terminating with a flame arrester anyway. Is that correct?

 

If I connect the vent to a vent terminal/flame arrester on the roof then the only way I'll know when the tank is full is from the sound changing as I pump fuel in, and I'll have squirted a few CCs of diesel over the roof of the boat at this point. Obviously I'd like to avoid that.

 

In addition I'd like to know when the day tank is nearly empty before the engine tells me by stopping. Browsing pics of vintage diesel engine rooms I notice most day tanks appear to have have sight gauges, so I want one too!

 

I think the easiest way to devise one is to connect a tee into the fuel outlet tube feeding the engine and connect it using a transparent tube of some sort to another tee in the vent pipe. This way I can see the level easily. Trouble is, I've a sneaky suspicion that most sight gauges done this way are a right bodge involving polythene pipe pushed onto copper tube stubs. Hardly secure but this is the only way I can think of to do it. Is there a better way? Does anyone here have a good quality, well designed secure sight gauge? What is the transparent section made from and what type of connectors are used at each end?

 

Many thanks,

Mike

 

(Edited to correct poor sentence construction.)

Edited October 30, 2010 by Mike the Boilerman

[ditchcrawler]

How about an overflow back to the main tank then just pump until full each day, I take it it is large enough to last all day?

[casper ghost]

Yes, i'm sure the vent should be outside. Most people can tell by the sound when it is nearly full, Mine, which I made myself, has an filler cap on top of the tank. I can unscrew this to look inside so it cheats the BSS by being called an inspection point..

Casp'

[BEngo]

My diesel fuel day tank has a bit of problem... Two problems actually.

 

1) I've no idea how much diesel it contains as I fill it, until fuel squirts out of the vent hole in the top.

 

2) I've a feeling the vent hole in the top is supposed to be connected to outside by a tube terminating with a flame arrester anyway. Is that correct?

 

If I connect the vent to a vent terminal/flame arrester on the roof then the only way I'll know when the tank is full is from the sound changing as I pump fuel in, and I'll have squirted a few CCs of diesel over the roof of the boat at this point. Obviously I'd like to avoid that.

 

In addition I'd like to know when the day tank is nearly empty before the engine tells me by stopping. Browsing pics of vintage diesel engine rooms I notice most day tanks appear to have have sight gauges, so I want one too!

 

I think the easiest way to devise one is to connect a tee into the fuel outlet tube feeding the engine and connect it using a transparent tube of some sort to another tee in the vent pipe. This way I can see the level easily. Trouble is, I've a sneaky suspicion that most sight gauges done this way are a right bodge involving polythene pipe pushed onto copper tube stubs. Hardly secure but this is the only way I can think of to do it. Is there a better way? Does anyone here have a good quality, well designed secure sight gauge? What is the transparent section made from and what type of connectors are used at each end?

 

Many thanks,

Mike

 

(Edited to correct poor sentence construction.)

 

The BSS does not like sight-glass level gauges. There are ways round this, by using "push to show level" valves at the bottom, but

they show a false level until 'pushed.'

 

A dipstick with a screw-in fitting is OK to BSS but you have to be able to get it on the top of the day tank and in/out so you can read it.

 

The overflow can go outside with its own flame arrester but IMHO it's better to drop it back into the main tank. That way you can hear when the day tank is full and not waste any fuel.

 

I just pump-up the day tank when I finish every day to full and know that it will run the engine for much longer than 24 hours if starting from full. YMMMV especially if you have a small tank.

 

N

[NB Alnwick]

We have a tapered plug (actually a BR Standard locomotive washout plug) fitted in the top of our day tank - when filling the tank, it is possible to remove the plug and put a finger in the hole as a makeshift dipstick, the tank is 'full enough' when the finger gets wet! This arrangement meets with BSS approval.

 

Tapered plugs can be obtained from Heritage Steam Supplies - a very useful company because they can also supply genuine worsted wool for making trimmings, proper exhaust wrap and lots of other interesting and useful stuff!

 

A proper boilerman would find their website absorbing!

 

[bargemast]

Thanks Graham, this really is a very interesting web-site.

 

Peter.

[Chris Pink]

My diesel fuel day tank has a bit of problem... Two problems actually.

 

1) I've no idea how much diesel it contains as I fill it, until fuel squirts out of the vent hole in the top.

 

2) I've a feeling the vent hole in the top is supposed to be connected to outside by a tube terminating with a flame arrester anyway. Is that correct?

 

 

 

The vent must vent to outside oe so that overfilling goes into the canal (illegal) rather than into the bilge (legal but BSS no-no) the same applies to the main tank fillers. In addition the day tank feed must be sealed to inside the boat.

 

As for a sight gauge, these are not compliant with the BSS except with historic boat exemption and usually consist of a tank connector or threaded stud with a nozzle attached and a piece of plastic pipe running vertical bent over at the top to avoid spillage. as this is an incredibly useful piece of kit what i would probably do is make up a bung to be fitted once every 4 years and the rest of the time have the sight gauge fitted. My sight gauge on my exempt boat has been there 45 years to my knowledge without posing a safety risk at any point.

[koukouvagia]

 

Trouble is, I've a sneaky suspicion that most sight gauges done this way are a right bodge involving polythene pipe pushed onto copper tube stubs. Hardly secure but this is the only way I can think of to do it. Is there a better way? Does anyone here have a good quality, well designed secure sight gauge? What is the transparent section made from and what type of connectors are used at each end?

 

 

My sight glass has got a valve top and bottom. The valves are specially designed for sight glasses because they have two protecting steel rods on either side.

I've replaced the plastic hose shown in this old picture with a 15mm polycarbonate tube. This is very strong and you can put an olive on it just as you would on copper pipe making a leakfree joint. Another advantage of using polycarbonate tube is that it doesn't discolour.