Fuel tank drain valve . . . ?

[Sea Ranch]

Greetings,

Wondering if anyone has experimented with installing a fuel tank drain valve or petcock, as opposed to the 1/4" BSPT plug the factory provided.

I ask because after finally wrestling the plug out of my tank's bung, it occured to me that draining fuel would be awkward and - especially - messy. It would flow down over the diff, chassis, et cetera, on it's way to splashing all over the place.

I want to be able to get rid of old fuel after the car has sat a while, or bad fuel, etc. Seems the best way would be to have a valve of some sort, that you could push a piece of tubing onto and run into a container so you could drain without making a huge mess. Wouldn't be too difficult - while the tank is out - to drill out the 1/4" BSP taper thread and tap it any way you like and fit, say, something like . . .

Looking forward to your thoughts, and debate . . .

Randy

[prezoom]

Totally agree with your concept, though I approached it in a different way. Needing an electric fuel pump for the Zetec, I started with a simple quarter turn ball valve in the trunk to completely shut off the fuel from the tank. I have increased the fuel line size to 5/16 from the tank, by making a new brass "ring" at the bottom of the tank with the new fitting. Then used a rubber fuel line into the trunk. I have removed that valve and installed an electric solenoid valve in its place. My plan for draining the tank, if needed, is to disconnect the line from the pump to the engine and use a piece of rubber fuel line with the appropriate connection, to pump the fuel to a container outside the car. Having an electric pump on my S2, I have used this process several times and seems to work well. The only drawback, is there will be some residual fuel left in the system between the solenoid and the outlet of the pump and the line to the engine, in addition to what is left in the rubber line to the outside container. Knowing I will have a minor spill, I think I can live with that.

With yours, you could remove the line to the tank, and install a line to a container. Easy if the car is raised, and only a minor spill from the fuel between the tank and the mechanical pump.

[Paul Chapman]

Great idea, however I would fit a valve that can be locked closed and with a threaded outlet so it could be fitted with a plug to prevent any leak to the outside if the valve opens/fails for any reason.

[mbell]

I think its a good idea. The thread outlet with cap and good method to fasten pipe to drain sounds good.

Personally I am impressed you managed to get the drain plug out. Even with my tank removed i was unable to get the dam thing out. I just drained it via the normal outlet with large funnel to catch the fuel.

[Sea Ranch]

Yeah, tough is right. Waited 2 years (during restoration) for some great brainwave. Soaked in various pentrating oils, etc. But in the end, had my son hold onto the bung with vicegrips, so I wouldn't twist it off, and I used vicegrips on the plug, worked it in both directions . . . I fully expected the plug to twist in half, but magically it came free

My alternative was to drill it out, etc. What a mess that would be.

[The Veg]

Even with my tank removed i was unable to get the dam thing out. I just drained it via the normal outlet with large funnel to catch the fuel.

Same here, only the petrol in mine was so old and perished that I didn't bother with the funnel. Cleaned some of the crud off the diff-housing in the process!

[John don]

Stick a rubber pipe in it and suck basic physics pardon my French