What Gasket Material for Diesel Tank Inspection Port ?

[Matt sachs]

Thanks for all the posts, as I am doing these very repairs this week. I have cut 4 access ports into the top of my aft keel to convert it to fuel storage. 3 of the ports get welded back. One will have a bolted on cover. I have scaled out all the rust. After sand blasting the inside, what a good coating to to apply inside the tank?

[boden36]

Matt, To a certain extent it depends on how thick the steel is. The thicker the plate, the longer it will take for corrosion to be a problem.
Our keel is tank 1" on the bottom, and 1/2" on top and sides. The interior of the fuel tank is unpainted.
I figured that getting a reliable paint film inside a keel tank was pretty difficult. Also was worried that if paint started falling off there would be real problems with blockages.
The tank has worked well for 25 years. Will inspect it in a couple of years - should be interesting.
Regards, Richard.

[simonthesailor]

I see that this post is a few months old, but I'm also looking for diesel tank gasket material. My question is why has nobody mentioned cork? It's cheap and easy to cut and I used it on a previous boat with no problems. Is there anything wrong with using cork?

[CDunc]

Nope 'sept the cork will dry out eventually.

[delmarrey]

If there is any biodiesel (methyl Oleate) in the mix then Teflon, Viton, and Nylon have very little reaction to biodiesel and are among the materials that can be used to update incompatible equipment.
Viton would be my choice because it compresses much better.

And if theses are not available then cork works but does ooz over time. It won't dry out if the boats in motion. Cork is what is used for fuel site equipment.

[ATC]

With cleaning fuel tanks we often have to cut holes, make plates, drill & tap bolt holes and replace gaskets. We get our rubber gasket material from Goodyear Rubber, when we need cork we go to Office Supply (cork sheets 2'X3').

[GordMay]

Originally Posted by simonthesailor

... Is there anything wrong with using cork?

Cork is compatible with both diesel & gasoline.

[Pblais]

I have seen inspection kits that include Vitron seals. All my tanks 1 water 2 fuel are stainless and have Vitron seals on the inspection ports to access all the baffles. After 20 years they seem just fine. Cork engine seals are fine but you always torque to specification. With a thick squishy Vitron seal you just can't mess up and nothing bothers them. If the tank isn't totally rigid you'll have a little extra seal thickness.

[simonthesailor]

Appreciate all the advice. I'm going to go with cork, especially as my inspection port is on the top of the tank so leakage is less likely (than if it was on the side).

Thanks!

[COLINFLTENG]

I need to make gasket for my diesel tank it is to seal pick up pipe for my walles heater think I will go with. Vilton rubber

[COLINFLTENG]

Sorry for my spelling viltron rubber

[sdowney717]

instead of a hole punch, take a propane torch and a nail.
Heat nail red hot and burn what ever hole size you want thru the gasket.

or perhaps a sharp drill bit. The hot nail makes a clean hole.

[delmarrey]

Originally Posted by COLINFLTENG

Sorry for my spelling viltron rubber

Actually that's Viton®.

And here's an excellent chart of synthetics for compatibility of chems/materials >> Cole-Parmer: Chemical Resistance Database

Although, it doesn't have cork. But if the cork is mixed with a compatible rubber/synthetic is seals well but it's life span will degrade with time. >>> http://www.gasketwiki.com/index.php?..._Rubber_Gasket

[COLINFLTENG]

Thanks spelling not very good ended not vilton rubber could not hands on it ended with nitrile rubber also known as Buna-N just got to make gasket now Cheers

[Therapy]

Originally Posted by rebel heart

I picked up a tube of this for $8 and so far it's working:

Amazon.com: Permatex 81724 #77 Sensor Safe Ultra Blue RTV Silicone, 3.35 oz. Tube: Automotive

The "right" way to do it is to have custom nitrile(nitrite?) gaskets made. If my $8 solution keeps working I'll be happy.

Not that I would use that in this case but I have used for lots of things. It is really great stuff.

And I know a guy who helped a poor person reassemble a gas engine who could not afford the gasket kit. Yep. Permatex Ultra Blue. Said it ran fine. Don't know how long though.