Flushing sediment out of gas tank

[johnbuckley]

Last week the '30 Tudor gas tank filter/shut off valve blocked with sediment/rust. I cleared it with a good blast of air through the carb fuel pipe, but it would be nice to try and flush the tank clean. I don't want to remove the tank. Any tips on easy/best way to do this in situ?
1) Is removing the shut off valve straightfoward, or am I likely to damage the tank in the process. (the valve has been undisturbed for at least 15 years).
2) can anyone convince me that the filter that projects up into the tank from the valve is a Useful Thing.- it seems to only add potential problems... a) it is difficult to clean. b) if it blocks when the tank is full you've got a lot of fuel to siphon out. c) it is unnecessary as there are a guaze filter at the sediment bowl and at the carb both of which are easy to access.

[roddyb34]

dont do what a local did with his 30 tank that had sandy residue and tried to vacuum clean it with his mums vacuum cleaner ,,,fumes into the cleaner and boom ,,,,mum not happy,,,

[Aerocraft]

The inserted filter has kept me off the side of the road for over ten years. The difficulty I face is tank "sealer" flaking off after having coated a clean tank with an aircraft grade sealer from Randolph Paint Co. when I restored the car in 1990. I inspect the tank annually and on occasion have had to fish out dime to quarter size "flakes" laying on the bottom around the drain hole.

I have always been able to get the valve out but have damaged it on occasion. Having a spare on hand is a worthwhile investment.

Gar Williams

[Patrick L.]

I'm wondering what luck to experience anyone has had that has just tried flushing the tank while still installed. I would really rather not remove these tanks.

[Brobrian]

I'm in the same position as you, John. I don't want to remove the tank and mess up the paint.
After experiencing some fuel related hiccups, and seeing sediment in my bulb, I flushed out my tank last week.
I took Tom W.'s suggestion and emptied the tank of gas then removed the petcock and "pencil filter" screen. I attached a drain line to the bottom of the tank and ran it to an empty gas can on the garage floor. Around the end of the drain line I wrapped a rag to use as a filter. Then I poured about 2.5 gallons of gas into the tank, rocked the car back and forth and let the gas drain out into the can on the floor. After each flush I checked my rag filter and repeated the process about 20 times until next to nothing was being caught in my filter. After cleaning the screen and the petcock (there was actually quite a bit of crud in the valve body itself) and cleaning the settlement bulb and screen, I'm pretty confident I'll be able to get along nicely for another 80 years.
By the way, I took off the carb and opened it up. There was a fair amount of sediment in the bowl as well.

[Tom Wesenberg]

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I had real good luck flushing a tank while installed. I removed the drain valve and installed a straight short pipe with a 3 foot length of hose. I held the hose high and installed 3 gallons of laquer thinner, then lowered the hose into a 5 gallon pail with cloth on top. I rocked the car back and forth as it drained. Once drained I repeated with the filtered thinner. I did this about 5 times and then installed the shutoff filter and told the owner to drain the glass sediment bowl when the very fine stuff showed in the bottom of the glass. This worked fine, and YES, the valve filter is a very good thing to have installed.

This is another reason I bought the electric fuel pump at the swap meet two weeks ago. I can put a large clear filter in the pump INLET and then to the tank drain, then run the outlet back into the gas tank. I can connect the pump to a battery charger and let it run for hours with an occasional rocking of the car. This will get most of the crap out of the tank.

Vince has posted about the "dirty leg" in the past, and this is another good way to keep driving while you clean the tank. Try doing a search for "gas tank dirty leg",

[Gary WA]

Thanks to the poster of picture. Here is the dirty leg works great.but clean often.

[BILL WILLIAMSON]

A chunk of a STRONG magnet, dropped in the tank, can help "collect" rust flakes that are migrating around. I break up old speaker magnets & use them for this. Also, I've NEVER seen a pencil filter plug up.
Bill W.

[johnbuckley]

Hey Bill, do you leave the magnet in the tank for ever, or do you dangle it on a piece of wire so you can retrieve it for wiping the rust off?

[Y-Blockhead]

Originally Posted by Tom Wesenberg

I had real good luck flushing a tank while installed. I removed the drain valve and installed a straight short pipe with a 3 foot length of hose. I held the hose high and installed 3 gallons of laquer thinner, then lowered the hose into a 5 gallon pail with cloth on top. I rocked the car back and forth as it drained. Once drained I repeated with the filtered thinner.

I've done this in the past but using a fine paint filter filter in place of the cloth.

I like your electric fuel pump circulating idea. You could use one of the large cleanable filters on the inlet of the pump. Just be careful of SPARKS...

[45GPW]

Originally Posted by Tom Wesenberg

Vince has posted about the "dirty leg" in the past, and this is another good way to keep driving while you clean the tank. Try doing a search for "gas tank dirty leg",

This one?

http://www.fordgarage.com/pages/kellyshutoff.htm

That's one of the very few non-OEM things on my Model A, all designed to make it a little more user-friendly and reliable. I've also got an additional visible and easily-serviceable fuel filter in that line to catch sediment before it gets to the sediment bowl on the firewall.

Another option I know some people have done in lieu of modifying the visible portion of the fuel line between the tank and the firewall is to install an extension above the tank outlet, so fuel is picked up above the bottom of the tank, but that way you lose some fuel capacity, depending on how high the extension is. The other downside to that one is that the sediment is still in the tank and continues to accumulate.

[Patrick L.]

'Dirty leg'. I like that. Simple, and, I like simple.

[BILL WILLIAMSON]

Originally Posted by johnbuckley

Hey Bill, do you leave the magnet in the tank for ever, or do you dangle it on a piece of wire so you can retrieve it for wiping the rust off?

Yo' Faraway John,
I just, "SET IT & FORGET IT"!!
Bill W.

[30Ford]

Put a strong magnet under the tank or in the tank ...it will keep the rust in one spot

[Brentwood Bob]

cow stomach livestock magnets from the feed store work for the external side of the tank. they were square when I bought a couple. the cylinder type would need to be ground flat on one side to keep them where you want them.
If you move them after having them inplace for a while you will probably plug up the downstream side.
bob

[olut]

Hi there,

from my experience, once you deal with rust inside the gas tank, any attempt to get it removed will not solve your problem.

Never "flush" the gas tank, the only way to remove sediments is vacuum, in Europe we have such devices, pneumatic air operated, creating a vacuum like a vac. This unit is used for those folks, who fueled their vehicles with the wrong product. However, there will be always something left and this will make your vehicle sooner or later to stop, most likely, where it is not comfortable.

My gas tank got removed, filled with rough sand, rotated for an entire weekend and afterwards epoxy-coated, no more problems. To sand it with dry ice is an option, however damages on welding/soldering might appear. Any other "experiments" will not work, tried them all....

Cheers
Albert

[ronn]

Had an old A pu that was mud inside the tank, ran a garden house in it for about an hour with the shutoff valve removed. You never saw so much sh-t come out where the sediment bowl attaches.

put the valve back in, loaded the tank with vinegar for a good 4-6 weeks and emptied it again. Install filters on shutoff and after sediment bowl-had no problem .......

[Harley03joe]

Originally Posted by 30Ford

Put a strong magnet under the tank or in the tank ...it will keep the rust in one spot

The Strongest Magnet I Ever Saw And Have 2 Is From A Computer Hard Drive

[Tom Cavallaro]

Most of the rust particles have lost their molecular structure so they will not go to a magnet! I flushed mine because of 40 years of rust, and used electrolysis and a 200 amp battery charger. No more fumes or that nasty smell of old gasoline. Baking soda wash is cheap! Used the compressor to clear the water out of tank because it kept getting blocked, just make sure your cap isn't on because you'll blow out the fuel gauge seal....when all done....used a vacuum with a half inch water tubing to suck out all the rust.....it my case was at least a half pound of rust. Three or four years now and never a problem...I also keep it coated using marvel mystery oil in every tank full. It's alittle work, but not like taking the tank out.

[Tom Wesenberg]

I agree with Tom about most rust won't stick to the magnet. Tom mentioned "BAKING SODA WASH", but you want to buy WASHING SODA and not baking soda. I did the electrolysis treatment to my very rusty Cub Cadet wheel that someone filled with calcium chloride. It took two days and came out rust free.