Sight tubes on Diesel Tank

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norseman

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Joined
Oct 8, 2007
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A friend is contemplating replacing his sight tubes on his tanks, as they are getting hard to see thru.* He has some clear pvc tube that is reinforced and his question is will the diesel break down the pvc?* Thanks for any help

Tom
 
Tom,
About 2 years ago I replaced my existing plastic site tubes with 1/2" acrylic tubing I sourced from my hose vendor. My original tubes were slipped over a short piece of galvanized pipe and then secured with a hose clamp. Pretty crappy looking. I had to cut a rubber bushing that fit beneath the brass nut that would pocket into the tank valve as part of the upgrade. The finished look was great. Cost was about $20 per tube as I recall. One tube took care of two tanks. I can probably find pictures if you want.
 
I'd like to see pics. We have the same tube set up as Norsemane and they are getting a bit opaque. Ours do not have valves at either end of the tubes. Do you or Norseman have them or, if not originally, did you install valves?
 
I changed mine out not long ago. I put back the same sort of stuff that was already there clear hose with fiber reinforcement it will stain again I am sure but was very easy to replace. I just ran the fuel level to about half, slipped the top of the tube off of the hose barb blew into the tube to force the diesel into the tank. Shut off the lower valve and put the new tube on didn't spill a drop.
Steve W
 
"Shut off the lower valve...."

On the sight tube or on the tank fuel feed?
 
David,
You will need to install valves on your sight tubes to be able to close off after checking your fuel level. Any tubing you use would need to survive a "five minute burn" which is impossible. Thus, you close the valves so it doesn't matter. I'm working on finding the pictures.
 
Tom, PVC won't break down in diesel, but it will discolor over time.* Site tubes give me the willies, and shut-off valves are mandatory, and should be closed unless you are reading the tank.* With shut off valves, you can even use reinforced and flexible clear water tubing, which is cheap and will last about 5 years before it discolors objectionably.* If you want the material that will meet the burn test, you have to go to the correct glass tubing.* These folks provide what you need:

http://www.pegasus-glass.com/producttype.asp?SuperCat=5

Hope that helps.
 
My chandler had some soft plastic tubing that was rated for Diesel. It has a slight yellow colour when new, and now after 6 or 7 years it hasn't changed colour at all, remains perfectly flexible and looking new.
I don't use it on my boat. Its on my heating oil tank at the cottage. I would be uneasy with sight tubes on the boat, in the ER where my tanks are. I use a dip stick if I don't trust just reading the hours since the last fill.
 
David,
I have failed to find the pictures I mentioned in my folders. Sorry. The next time I am on board I will try to snap a few.
 
Forkliftt wrote:

David,
I have failed to find the pictures I mentioned in my folders. Sorry. The next time I am on board I will try to snap a few.
No problemo. Thanks for looking.

*
 
Thanks for*the info.* I have forwarded all of the replys to my friend and I'm sure that he will find them very helpful.

Tom
 

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