Fire retardant sight glass for day tank

[by'eck]

With the first BSS check due on my boat this year, I'm looking for a replacement for the reinforced plastic hose presently used, as shown below. Maybe lexan but obviously see through.

 

 

From memory I think the metal fittings are 3/8" BSP. I could just blank off unions temporarily but would prefer something permanent and legal.

[Woodsy]

Not sure about type of glass, but in the commercial world all sight glass must have a self closing valve on the bottom. I have seen many different types from commercial off the shelf to home - sorry ship made weights (lead sinkers, plumb bobs etc) holding the opening lever closed.

[koukouvagia]

I use 15mm polycarbonate tube. It's claimed to be virtually unbreakable and has the advantage of being able to accommodate compression fittings. I've had no trouble with BSS.

[by'eck]

Not sure about type of glass, but in the commercial world all sight glass must have a self closing valve on the bottom. I have seen many different types from commercial off the shelf to home - sorry ship made weights (lead sinkers, plumb bobs etc) holding the opening lever closed.

 

Yes remember sourcing self closing valves, although I believe they were required top and bottom. Defeats the object of a remotely viewable sight glass though. Wonder if such would be acceptable with my present plastic hose with the creative (temporary) addition of your afore mentioned lead weight to hold it open.

I use 15mm polycarbonate tube. It's claimed to be virtually unbreakable and has the advantage of being able to accommodate compression fittings. I've had no trouble with BSS.

 

Thanks - will have a look.

[RLWP]

I use 15mm polycarbonate tube. It's claimed to be virtually unbreakable

 

How do you cut it to length then?

 

Richard

[koukouvagia]

Just to add a picture of my set up.

 

 

How do you cut it to length then?

 

Richard

 

(To be serious for a moment, it'll cut with a hacksaw. It won't shatter, though.)

[Graham.m]

Maybe have a look at the BSS page 12 http://www.boatsafetyscheme.org/media/268789/ecp-private-boats-ed3_rev2_apr2015_public_final.pdf

 

I think from what I can see you are OK as long as the tank is less than 27 litres

[Loafer]

With the first BSS check due on my boat this year, I'm looking for a replacement for the reinforced plastic hose presently used, as shown below. Maybe lexan but obviously see through.

 

 

From memory I think the metal fittings are 3/8" BSP. I could just blank off unions temporarily but would prefer something permanent and legal.

 

Your engine room looks very Hudsonesq - is it?

[ditchcrawler]

To save a lot of reading

[by'eck]

 

Your engine room looks very Hudsonesq - is it?

 

Yes - you an an eye for excellence

To save a lot of reading

 

Thanks dc.

[DHutch]

To save a lot of reading

So if the tank is sub-27L you are fine.

 

 

Daniel

[Graham.m]

So if the tank is sub-27L you are fine.

 

 

Daniel

 

That is what the note at the bottom says

Edited January 18, 2016 by Graham.m

[DHutch]

That is what the note at the bottom says

Yes...?

[by'eck]

I use 15mm polycarbonate tube. It's claimed to be virtually unbreakable and has the advantage of being able to accommodate compression fittings. I've had no trouble with BSS.

 

Sorry to raise this subject again but returning to boat tomorrow with a length of 15mm O/D (1.5mm wall) polycarbonate tubing. Intend to order unions below to screw directly into tank fixings after confirming they are in fact 3/8" BSP

 

 

Question given your experience, is will the standard brass olive seal against the polycarbonate tube ok. Just a bit concerned about overtightening.

[bizzard]

 

Sorry to raise this subject again but returning to boat tomorrow with a length of 15mm O/D (1.5mm wall) polycarbonate tubing. Intend to order unions below to screw directly into tank fixings after confirming they are in fact 3/8" BSP

 

 

Question given your experience, is will the standard brass olive seal against the polycarbonate tube ok. Just a bit concerned about overtightening.

Viton o ring would be safer, they do 3/8''ID 1/16'' thick. possibly thicker.

[koukouvagia]

 

 

 

Question given your experience, is will the standard brass olive seal against the polycarbonate tube ok. Just a bit concerned about overtightening.

I just nipped the olive up and it was fine. (I did have an extra length of polycarbonate, though, in case I cracked it!)

[by'eck]

Thanks to you both. Have used brass compression fittings on hard neoprene tubing and been impressed on disassembly how well the olive grips. I too have spare tubing so will try with olive first.

[national velvet]

Without a doubt sir, your boat should fail the test because of the following:-

The day tank must have an isolation valve at the top and bottom of it.

In-between the 2 valves should be a glass tube, protected by at least 2 brass bars.

The theory is you should travel on your boat with both the top and bottom isolation valves closed. This is because if the glass tube shatters the only diesel that escapes is in the tube. Obviously the top and bottom valves are opened before pumping up the diesel, to ascertain the level, and then closed when completed. As per photograph of my day tank.

[WotEver]

Without a doubt sir, your boat should fail the test....

I can't see that anywhere in the BSS book. The only relevant entry is with regard to auto shut-off valves...

 

See 2.6.2 note 2 here: http://www.boatsafetyscheme.org/media/268789/ecp-private-boats-ed3_rev2_apr2015_public_final.pdf

 

Tony

[koukouvagia]

I can't see that anywhere in the BSS book. The only relevant entry is with regard to auto shut-off valves...

 

See 2.6.2 note 2 here: http://www.boatsafetyscheme.org/media/268789/ecp-private-boats-ed3_rev2_apr2015_public_final.pdf

 

Tony

 

I have never seen a day tank on a narrow boat with self-closing valves. I have precisely the same set up as National Velvet. I think that provided the day tank capacity is less than 27l and/or in a ex-working boat the BSS regulations are complied with.

[springy]

There are two separate notes :-

 

"NOTE – self‐closing valves are not required for fuel gauges on any diesel‐fuelled vessel formerly used for the

commercial carriage of freight or passengers or as a tug or as an icebreaker and which is to be licensed for use

as a pleasure vessel, or registered for use as a houseboat, unless used for the purposes of hire or reward.

Documentary evidence of former use addressed to the BSS manager is required to enjoy this exception.

NOTE – self‐closing valves are not required on sight gauge arrangements on day tanks having a

maximum capacity of up to 27 litres."

So if you have Documentary Evidence and write to the BSS manager then self closing valves are not required

on any sight glass/fuel gauge as originally installed.

Or if the tank is less than 27L - self closing valves not required.

springy

Edited February 25, 2016 by springy

[WotEver]

The day tank must have an isolation valve at the top and bottom of it.

In-between the 2 valves should be a glass tube, protected by at least 2 brass bars.

Where does this come from?

 

Tony

I have never seen a day tank on a narrow boat with self-closing valves.

Me neither.

 

Tony

[by'eck]

Thanks to you both. Have used brass compression fittings on hard neoprene tubing and been impressed on disassembly how well the olive grips. I too have spare tubing so will try with olive first.

 

This is the result using polcarbonate tubing with 1.5mm wall thickness. Much easier to see fuel level now.

 

 

Although apprehensive nipping up the compression fittings onto polycarbonate tubing, I got leak proof fit first time without breaking anything. In fact when I unscrewed old unions I found the threaded hole in the lower boss out of true. Fortunately the compression fitting design does provide a little lee way for angular mismatch.

 

Next question is what tube protection would be acceptable to satisfy BSC check. Was considering a strip of brass plate bent to a curvature around back of glass and shaped at top and bottom to be secured with hose clips onto right angle unions. Should be at least as protective as a pair of brass rods each side.

[by'eck]

Final incarnation which has received BSS examiner approval.

 

 

30mm ID copper tube was split along its length with Dremel cutter to provide 180° protection to sight glass.

Edited July 30, 2016 by by'eck

[David Mack]

The angle fittings each end screw into the bosses welded onto the tank. So how did you then fit the clear tube into the fittings each end?