Bad Valve on Fuel Tank

[Chip W]

I have a 1984 Island Gyspy trawler. I have four steel fuel tanks. The starboard aft tank has a valve that must not be able to completely close tightly as fuel from the forward tank is making its way into the aft tank. It is regular gate valve that looks like a spicket used for a water hose. I have not been using the aft tanks. I ran the boat using the aft tank to decrease the fuel there, but found water in the racor filter. Therefore, I would like to replace the valve so I can completely shut off the aft tank. I don't know where to find a replacement valve. Does anyone have any suggestions? I tried to attach a picture of it, but am not sure it is attached.
Thanks.

 

[O C Diver]

If nothing else, you could shut off the valves, remove and cap the line, drain the tank, remove the valve and plug it.

Probably a good idea to put a note on the tank as to why it's been disconnected.

Ted

 

[kchace]

You'll have to empty the tank first. If the fuel level is low enough you could transfer it to the other tank. Then you should replace with a proper fuel shut off valve.


Ken

 

[syjos]

I would replace that gate valve with a ball valve.

It should be a standard pipe thread.

 

[KnotYet]

Greetings, Chip.
The selection of angle valves you can replace that one with is dizzying.
I suggest checking McMaster-Carr Supply online for one that fits that space.

You'll need to know the pipe thread size and the type of copper tube fitting to use.
That valve may have been damaged by water and junk in the bottom of the tank.
It would be great to clean out that tank and put it back into service.

Also, is it possible that the diesel return flow enters that tank somewhere else?

 

[C lectric]

I had this kind of nonsense, gate and/or water spigot [globe] valves and changed to ball valves. Remove the fuel from the tank. Shut off any other valves that can feed this valve which you seem to have. Pump the fuel into another tank or into a drum on the dock. Check with marina.
You will need to drain the hoses themselves into a small pan and then plug the ends and then secure them UP somewhat so they don't dribble.

The valves can then be removed and replaced. Of course most ball valves are brass but there are some bronze available from places like Groco and Buck Algonquin.

Actually SS ball valves are available so look , ask, for those. You may have to look up a valve supply house or ask a marine supply house.

Regardless use a fitting that will be an intermediary between the new ball valve and the steel tank or corrosion of the tank may occur if water becomes present. THis is important. Can be SS or a regular iron ftg. I see an iron bushing fitting between the tank and the valve. Use that.
If no water then corrosion will not occur but at the tank bottom that cannot always be guaranteed.

You will need some other bits and pieces to adapt the hose to the new valve and turn the valve output in the direction needed. Elbows and such.

Use a good sealer such as Rectorseal #5 or Permatex Aircraft sealer, black and messy but a good sealer.

I just realized your fuel feed line seems to be copper right to the valve. THat will have to be reckoned with. Noted by Knotyet.

 

[Comodave]

Does the forward tank have a shutoff valve on it? If so is it off and leaking? That may be where you need to replace a valve. I would rather have the fuel shut off at the source than the end of the fuel hose. Because if there is the ability for fuel to leak out of the hose that could be a huge issue if the hose starts to leak.

 

[Chip W]

Thanks for everyone’s replies. I am planning on pumping the fuel to the forward tank and/or another container and get the tank as empty as possible. The valve on the forward tank is good. It had been open before I realized I had the problem (with the aft valve closed). Once the tank is empty, I will take off the valve. I didn’t know where to get another one so your comments will help. I will try Mc master as I hadn’t thought of that. Once I get into it, I’expect I may get back to everyone with more questions. Your comments were most helpful. Thanks. Chip W

 

[Comodave]

Oh, BTW, welcome aboard. Yes, McMaster Carr is a great source for lots of things. And their service is great too.

 

[Nick F]

As C-lectric says, it is not a gate valve. It is a "globe valve" and internally has a plunger that gets pushed up against a hole (the seat), very similar to old style sink faucets or the common hose bibb. (As regards the problem/fix this comment is academic, by the way, but its nice to get the terminology right)

I saw posted on the site an interesting trick for avoiding fuel loss when changing out a valve like this with fuel in the tank. Connect a vacuum cleaner to the top of the tank (filler or vent). (I have not personally tried this!)

 

[Giggitoni]

I would replace that gate valve with a ball valve.

It should be a standard pipe thread.

This^. Ball valves (SS) are the way to go.

 

[C lectric]

As C-lectric says, it is not a gate valve. It is a "globe valve" and internally has a plunger that gets pushed up against a hole (the seat), very similar to old style sink faucets or the common hose bibb. (As regards the problem/fix this comment is academic, by the way, but its nice to get the terminology right)

I saw posted on the site an interesting trick for avoiding fuel loss when changing out a valve like this with fuel in the tank. Connect a vacuum cleaner to the top of the tank (filler or vent). (I have not personally tried this!)

I did try it and it worked. THe catch was the tank was far smaller, the fuel level was already down, the valves were very small, I had good access so the swap went very quickly with not too much chance of a mess.

Last but not least I was able to test the effect before I committed.

One crumby valve, can't remember the specific type name though although more of a petcock, for a new ball valve.

 

[rgano]

I once replaced the plugs, like the one seen behind the valve in question, on all four of my tanks (two 190- and two 130-gal capacity). They were all half or more full. I put on lockk with a lockable ball valves because I wanted to be able to regularly drain off the bottoms of my tanks. I unscrewd the plug at each tank and simply screwd in the new valve. Lost a few ounces into diaper and container at each tank. I was quick!

 

[slowgoesit]

You can replace the valve without draining the tank. Plug the fuel tank vent outlet, and put a shop vac on the fuel tank fill fitting. Turn on the shop vac, unscrew the fuel valve, ensure that the threads are clean, and install the new valve, using suitable pipe thread. Turn off the shop vac, and unplug the vent. Done deal. DON'T do this with a gasoline tank, only diesel.

 

[rslifkin]

DON'T do this with a gasoline tank, only diesel.

Fortunately, marine gasoline tanks don't have fittings below the top of the tank anyway, so there should be no reason for anyone to get stupid with a shop vac and blow themselves up.

 

[Datenight]

You can replace the valve without draining the tank. Plug the fuel tank vent outlet, and put a shop vac on the fuel tank fill fitting. Turn on the shop vac, unscrew the fuel valve, ensure that the threads are clean, and install the new valve, using suitable pipe thread. Turn off the shop vac, and unplug the vent. Done deal. DON'T do this with a gasoline tank, only diesel.

I did this on a home oil tank, 275 gallon with about 80 gallons of fuel. Worked fine.

Rob