fuel tank inspection ports

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Oct 7, 2007
Vessel Make
Bayliner 4550 Pilothouse
I want to take the covers off my fuel tank inspection ports and see how things are looking in there.* Seller suspected starboard tank was leaking.* If it was I am 110% sure it was a leak that is higher than the current fuel level as there is definitely no leak right now at all.* I am still not sure there ever was a leak from the tanks as he was not sure but anway...I wanna poke my head in there and take a gander, particularly since I want to put some more fuel in the tanks this weekend.* :)
So my question is- what do you reseal the inspection ports with when done??* Assuming if they are even sparkling and all pretty inside, I won't be filling them up to the inspection ports but I do want to seal them properly.* What say ye?
Also, let's say I inspect and they look ok or they look bad and want a second opinon or whatever.* If I just reinstall without sealing and don't put any fuel in them at even a level that sloshing around couldn't get fuel up to that level, will temporarily re-installing without a sealant mean that i will have stinky diesel fumes going everywhere driving my wife crazy?* :)

Use a good jointing material like firefly or oilite. Don't use rubber insertion but nitrile is ok.
With the jointing material you would probably use a soft non harding compound but not something like stag that will go hard, or just some kopperkote or graphite grease, nothing with the nitrile.

Permatex makes several different fuel resistant Form-a-Gasket products that are suitable for sealing the inspection plates. Should find them at your closest auto parts store.
Wow... Good stuff. I was thinking about doing the same this Fall. Thanks!
We used Viton/Buna-N for our tanks.* I have been told that EPDM is equal in compatibility with diesel but is a little cheaper.* I think*we paid ~$20.00 FOR 12"X12"x1/8" sheet.** What we liked about the Viton was that it is ready to go as soon as the bolts are tight and it was easy to get equal torque on all the nuts.

Hobo KK42
La Paz, BCS, MX**

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