Reply
 
Thread Tools Display Modes
 
Old 12-31-2015, 11:38 AM   #21
Guru
 
City: Melbourne, FL
Country: USA
Join Date: Dec 2014
Posts: 916
Get a machine shop to build a channel for the tubing. ABYC has two fears. One is fire, and two is something falling against the tubing, pulling it off the hose barbs and filling the bilge with fuel.

The commercial sight gauges have a milled aluminum channel that protects the tube from impacts. It also slows the heat from fire from cracking / melting the site tube. If they use glass, they use borosilicate sight glass, to better tolerate temperature. They often have banjo bolts mounting the whole rig at the top and bottom and valves at the top and bottom.

If you have a vented / open pipe, you don't need two valves, just one at the bottom.

You could put a solenoid valve at the bottom of each sight gauge and trip them all at once. Use a momentary contact switch for that so they stay shut with no power applied.
__________________
Advertisement

stubones99 is offline   Reply With Quote
Old 12-31-2015, 11:46 AM   #22
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Quote:
Originally Posted by WesK View Post
Quote:
Originally Posted by Marin View Post
The tubes are PVC flexible tubing.
PVC will melt if there's a fire.
So will the boat.
__________________

Marin is offline   Reply With Quote
Old 12-31-2015, 11:52 AM   #23
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Quote:
Originally Posted by stubones99 View Post
... is something falling against the tubing, pulling it off the hose barbs and filling the bilge with fuel.
Our small diameter sight tubes hold about a quarter cup of fuel if that. With the valves properly closed, pulling one off a hose barb will not "fill the bilge with fuel."
Marin is offline   Reply With Quote
Old 12-31-2015, 12:17 PM   #24
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,442
I think this is being over-thought. With them closed, minimal/minor fire hazard, maybe a teacup full of fuel at most in the lines. If the valves leak, replace them. If they don't and you forget lots then bungee the handles. Shock cord is available everywhere. Somebody mentioned lock wire (which I use lots) but it will drive you mad redoing that every time you need to look at the quantity, even with good lock wire pliers.
__________________
Don't believe everything that you think.
Xsbank is offline   Reply With Quote
Old 12-31-2015, 01:31 PM   #25
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 1,602
Thanks to all for your contributions. WesK: your comments essentially mirrored those of my surveyor. When I asked him about ABYC standards, he said he didn't care what those were. He considered the NFPA as the authority on the subject. There was a to-and-fro with between the PO and the surveyor on this issue. PO thought everything was to specifications. Surveyor pointed to the fact that even the fuel in the tubes represented a hazard, in the event of a fire. Note that another highly regarded surveyor from the PNW didn't identify an issue with the site tubes at all.

Here are the steps I want to take:

1) get the Doug the welder, who knows a thing or two about marine fuel tanks, to assess the materials that have been used for the fittings, whether there is an issue with possible corrosion in the future and then decide if other fittings need to be replaced as well. I need to first determine if I have available free capacity in the other tanks in order to change the valves.

2) at the very least replace the bottom valves on all four tanks with something that is self closing.

3) look into enclosures for the site tubes.

While two of the valves currently "weep" only when open, a more complete failure at a later time might be a much bigger issue. Best to nip it in the bud before it becomes more serious. I've been trying to contact the PO for some history without success.

Thanks Clectric for the local source for valves. I'll see what additional actions Doug suggests and proceed from that point.

Jim
JDCAVE is offline   Reply With Quote
Old 12-31-2015, 01:35 PM   #26
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
Quote:
Originally Posted by JDCAVE View Post
Thanks to all for your contributions. WesK: your comments essentially mirrored those of my surveyor. When I asked him about ABYC standards, he said he didn't care what those were. He considered the NFPA as the authority on the subject. There was a to-and-fro with between the PO and the surveyor on this issue. PO thought everything was to specifications. Surveyor pointed to the fact that even the fuel in the tubes represented a hazard, in the event of a fire. Note that another highly regarded surveyor from the PNW didn't identify an issue with the site tubes at all.

Here are the steps I want to take:

1) get the Doug the welder, who knows a thing or two about marine fuel tanks, to assess the materials that have been used for the fittings, whether there is an issue with possible corrosion in the future and then decide if other fittings need to be replaced as well. I need to first determine if I have available free capacity in the other tanks in order to change the valves.

2) at the very least replace the bottom valves on all four tanks with something that is self closing.

3) look into enclosures for the site tubes.

While two of the valves currently "weep" only when open, a more complete failure at a later time might be a much bigger issue. Best to nip it in the bud before it becomes more serious. I've been trying to contact the PO for some history without success.

Thanks Clectric for the local source for valves. I'll see what additional actions Doug suggests and proceed from that point.

Jim
I think you will be safe with those modifications. Also, if you get everything ready ahead of time you could change the valves without too much spillage. Have a container and rags to catch the fuel and dispose of it safely.

Most folks recommend pipe dope, not Teflon tape on fuel fittings. Get everything assembled and doped up then remove the old and quickly install the new. You could even block the tank vent to slow leakage.
rwidman is offline   Reply With Quote
Old 12-31-2015, 07:00 PM   #27
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,424
Mine are from Ballard Hardware (Seattle)

They have a ball inside which stops high flow in the event of a breakage. Also note the brass rods that run down to lower valve either side of the tube. The sound insulation effectively makes a recess for the tubes to lie in.
Attached Thumbnails
Click image for larger version

Name:	Sight gauge valve sml.jpg
Views:	59
Size:	91.2 KB
ID:	47789  
__________________
Brian
Insequent is offline   Reply With Quote
Old 12-31-2015, 09:51 PM   #28
Guru
 
City: Venice Louisiana
Country: United States
Join Date: Dec 2013
Posts: 1,097
I guess I just dont get it. Install industry standard sight tubes and stop worrying. Maybe they just cost to much $$$.
kulas44 is offline   Reply With Quote
Old 12-31-2015, 10:03 PM   #29
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 1,602
Quote:
Originally Posted by kulas44 View Post
I guess I just dont get it. Install industry standard sight tubes and stop worrying. Maybe they just cost to much $$$.

Provide more details please. For example I saw some fancy magnetic setup on a Selene last summer that cost about $7,000. Outa my range I think.


Jim
Sent from my iPad using Trawler Forum
JDCAVE is offline   Reply With Quote
Old 01-01-2016, 02:12 AM   #30
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
Quote:
Originally Posted by JDCAVE View Post
Provide more details please. For example I saw some fancy magnetic setup on a Selene last summer that cost about $7,000. Outa my range I think.


Jim
Sent from my iPad using Trawler Forum
Exactly. What industry and what standard?
Capt.Bill11 is offline   Reply With Quote
Old 01-01-2016, 09:50 AM   #31
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
Standards for "industry" and standards for boating could be quite different.


And there's a cost point where it's not worth it, just plug the tank holes and use a different method.
rwidman is offline   Reply With Quote
Old 01-01-2016, 01:12 PM   #32
Guru
 
hollywood8118's Avatar
 
City: Port Townsend Washington
Country: USA
Vessel Name: " OTTER "
Vessel Model: Ocean Alexander Europa 40
Join Date: Nov 2009
Posts: 1,482
I think Marin is correct that this is being way overthought.. the risk of the existing valve working its way open is next to 0.
Everything in the E.R. is combustible.. the small amount of fuel in that sight hose is small compared to the spare gallons of oil we all carry in our E.R.
The bigger risk is loose items that can cause damage in a seaway. Who would leave the valve open when checking fuel levels.. my hand never comes off the bottom valve.. open it for about 5 seconds then close it.. done deal.
My solution is to replace the tubing often so it does not get cloudy of brittle.. then I don't worry about the tubing fracturing and causing a leak.
Finally glass sight tubes even with protection have always scared me.. sometimes in foul weather our boats take a pounding and a 36" to 48" long glass tube isn't that strong.
Happy New Year,
HOLLYWOOD
hollywood8118 is offline   Reply With Quote
Old 01-01-2016, 03:37 PM   #33
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,858
Push Button Sight Gauges
Attached Thumbnails
Click image for larger version

Name:	ATK-20SIGHT-20GAUGE-20SCHEMATIC.jpg
Views:	56
Size:	13.1 KB
ID:	47807  
psneeld is online now   Reply With Quote
Old 01-01-2016, 04:49 PM   #34
Guru
 
AusCan's Avatar
 
City: Adelaide
Country: Australia
Vessel Name: Kokanee
Vessel Model: Cuddles 30 Pilot House Motor Sailer
Join Date: Jul 2012
Posts: 2,091
Quote:
Originally Posted by hollywood8118 View Post
I think Marin is correct that this is being way overthought..
HOLLYWOOD
+1
Agree - Don't get too worked up about it.

99.9% of valves have teflon or nitrile seals that will fail in a fire. Then there's the fuel lines themselves, and what about poly tanks?.

One other simple precaution you can take is to share one sight tube between the two tanks (fitted on the equalising line). It will reduce the risk of failure by 50%.
__________________

AusCan is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 12:21 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012