Very fine rust in gas tank-what to do?

[Fred K-OR]

Would like some ideas about what to do with a gas tank that is sending some very fine rust particles into the fuel system. They make their way through 3 new filters in my system-one in the tank, one in the settling bulb and one in the carb. These particles when you blow on them when dry, act like dust.

I have replaced my cast iron settling bulb with a glass one to try to catch some of this rust. Within a very short time, the glass bulb is doing it's job, it picks up a lot of rust. My thoughts in putting this glass bulb in was that over a period of time, the stuff in the tank would all collect in the bulb and after a period of time, it would clean my tank.

I would like some other ideas on what to do other that taking the tank out of the car and doing a complete cleaning and maybe a lining. Is there a rinse that would get this stuff out? If so, how would a person go about it?

Thanks again for any ideas you may have.

[329s]

Fred,

Try an "in-line filter" for a while. This will require an new fuel filter to carb gas line with the in-line filter situated somewhere in the middle of the line and maybe in time will solve the problem.

Just a thought.

Here is a thought...Oxlic Acid works great when cleaning minor rust stains on old steel beer cans. I wonder what it would do to the inside of the gas tank.

I do not recomend adding it to the gas as I do not know what the outcome would be if the oxalic acid and gas mixture went through the carb and engine.

Hmmmmmm...better stick to the in-line filter for a while.

Pluck

[Mitch//pa]

I would put one of these filters in the bowl they work great. No particles will get past it to the bottom of the bowl. Nothing needs to be altered to install it

[[email protected]]

Harbor Freight sells small rare earth high powered magnets that look similar in size to hearing aid batteries. Put one of them in the bottom of the glass sediment bulb. It will capture all of the rust before it gets to the carb. When it gets loaded up clean out the sediment bulb and blow off the magnet with a high air pressure nozzle.

[Fred K-OR]

Thanks guys. I think I have a small magnet around here somewhere that I can put in the bottom of the glass sediment bulb. Will give that a try along with maybe some patience over a period of time to see how much of this crud I can pick up. Some of the vendors sell a "fine particle" type of filter that a person can put inside of the glass bulb that I may give it a try also.

Pluck I think I will leave the acid as a last resort.

[steve s]

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I wouldn't attempt an acid treatment, even as a last resort. It will get into the seams and be virtually impossible to completely remove, possibly resulting in more corrosion and leaks.

In my experience and everyone else I know who's tried one, those ultra-fine filters don't work. They either plug up real fast, dissolve from the ethanol, or serve as vapor lock site. You might get five or ten miles, but be prepared for a roadside removal. My guess is that they only work for folks whose system is so clean they don't really need them, which would not be you. If you ask around among your Model A friends, they will probably give you one to try from their junk box--I would.

Also, the inline filter caused total vapor lock for me, but that's a very variable thing.

Maybe the rust is so fine it won't cause a problem. Does it? leaking float valve, plugged jets?

I pulled my tank and had it cleaned and sealed at a Renu franchise, about 15-20 years ago.

Steve

[Fred K-OR]

Originally Posted by steve s

I wouldn't attempt an acid treatment, even as a last resort. It will get into the seams and be virtually impossible to completely remove, possibly resulting in more corrosion and leaks.

In my experience and everyone else I know who's tried one, those ultra-fine filters don't work. They either plug up real fast, dissolve from the ethanol, or serve as vapor lock site. You might get five or ten miles, but be prepared for a roadside removal. My guess is that they only work for folks whose system is so clean they don't really need them, which would not be you. If you ask around among your Model A friends, they will probably give you one to try from their junk box--I would.

Also, the inline filter caused total vapor lock for me, but that's a very variable thing.

Maybe the rust is so fine it won't cause a problem. Does it? leaking float valve, plugged jets?

I pulled my tank and had it cleaned and sealed at a Renu franchise, about 15-20 years ago.

Steve

Before I put on the glass bulb, the fine rust got through all filters and accumulated on the inside end of the filter in the carb along with some in the old cast iron bulb. I took off the carb, took it apart and used air to blow it out of the carb. A lot came out of the carb. Before I did that, if you recall an earlier post, I had a problem of the rig acting like it ran out of gas. I would let it set for awhile and it would restart and go for awhile then stop again and again and again----. So I think this garbage in the tank was giving me a problem.

I think I will put the magnet in the glass bulb and let it run for awhile and see what happens. May still have to pull the tank.

[JimK1930A]

Mitch,
Where did you get that filter I see inside your glass sediment bowl?
What is the brand and or part number?
Thank you in advance.
Jim

[[email protected]]

Originally Posted by JimK1930A

Mitch,
Where did you get that filter I see inside your glass sediment bowl?
What is the brand and or part number?
Thank you in advance.
Jim

Looks like it is a NAPA p/n 3034. I don't like any of this type of filter unless you use a fuel pump. Gavity fuel feed does not have a lot of pressure.

[1crosscut]

Perhaps you can speed the process up a bit by using a 12 volt fuel pump. Rig a short section of fuel line from your sediment bulb / filter and hook up the pump with a line back into your tank. Let it run for a while shaking the car once in a while to keep things in suspension.
Dave

[Jerry Parr WI]

Two kinds of rust show up in the gas tanks. The chunks of rust that form in the bottom from water setting and the fine talcum powder rust that forms on the inside top of the tank from condensation. Sounds like you have the second type. The fine rust gets washed off the tank by the sloshing gas when the car is driven. The best way to get rid of it is drive until its gone. Severe cases will plug the shutoff valve but it quickly drives away. Small amounts don't seem to plug anything except filters and just run thru the carb. Once it's washed away driving the car on a regular basis keeps it from being a problem.

[Tacoma Bob]

For what it's worth...............I run with the "pencil" filter in the gas shut off valve body and the Napa 3039 (or in my case the Wix 3039) in my glass sediment bowl. Been running this way for 10 years with no problems. I had lousy luck with those damn micro filters.

[Fred K-OR]

Thanks again for the ideas guys. I think the idea of driving it may work. So will give it a try but I think I will stay close to home for awhile.

[Napa Skip]

I believe a magnet will be only marginally effective in trapping the fine reddish rust coming out of a Model A gas tank.

Short answer: While iron (and its alloys that are referred to as steel) is magnetic (generally speaking; an exception is most – but not all – stainless steels; try getting a magnet to adhere to your stainless steel headlamp shells or radiator cowl) during oxidation the unpaired d-shell electrons (which give iron atoms their magnetic moment) bond with – typically – oxygen with the result that the magnetic moment that results in ferromagnetic properties is lost. [I couldn’t find “…d-shell electrons…” in my copy of the Service Bulletins, but I’m certain it’s in there somewhere…]

Longer answer: There are numerous oxides of iron (about 18 or so), the most common of which are black iron(II) oxide (FeO or ferrous oxide); dark blue-black iron(II,III) oxide (Fe3O4 or magnetite) and reddish iron(III) oxide (Fe2O3 or – as a naturally occurring element - hematite). Usually, in the presence of oxygen and absence of a high-temperature acidic or basic environment, red rust is formed. In other environments, a tight blue-black compound such as Fe3O4 can be formed, the most common example of which is the bluing used on firearms (although the actual color of the “bluing” can be controlled by changing the pH of the bluing bath). Thus that midnight-blued rifle you’re so proud of is really just a rusted chunk of steel, albeit a nicely rusted chunk of steel.

Empirically, if you have a glass sediment bowl with red rust in the bottom (and no internal filter held in place by a steel spring) you might test this by attempting to drag some of the fine red rust up the side of the glass bowl with a magnet. You may get a small trace of sediment to drag along, but I suspect this is impurities in the rust. At least the fine red rust in the glass container in which I keep the rust that has been settling out in my sediment bowl for 35+ years does not respond to a magnet.

Filter comment: the unaided firewall sediment bowl (in my experience) ought to entrap most of this sediment, with a finger filter that fits inside the gas tank shut off valve taking care of the larger chunks. I’ve used a micro filter inside the sediment bowl but – in my experience and as pointed out in other posts above – they rapidly clog, leading to the bewildering experience of satisfactory idle and low/moderate speed operation but – at about 45 mph – leaning, loss of power and backfiring as the amount of fuel delivered to the carburetor falls below the amount needed to sustain high speed operation. Inevitably this occurs on a warm day leading to the ‘ah-ha’ moment of “by Jove, it must be vapor lock (or a failed condenser, or…)” only to discover that not to be the case.

[Fred K-OR]

Thanks Skip for your answer. I will have to go try my magnet and see what I get.

[steve s]

Originally Posted by Napa Skip

... At least the fine red rust in the glass container in which I keep the rust that has been settling out in my sediment bowl for 35+ years does not respond to a magnet. ... .

Wow, I thought I was bit obsessive about saving my old parts, but I am unworthy!

Also, I, for one perhaps, appreciated the d-electrons digression. When this comes up, I always agonize over pointing out that rust isn't supposed to be magnetic, but don't want to argue with all the folks who claim to have watched it coat their magnets--small bits of occluded metal, I presume. But, still, surprising.

Steve

[steve s]

While we're on the subject, here's my picture of all of the filters I've tried and abandoned over the years. The only one that wasn't a big problem was the reddish fiberglass model, which is no longer available.

[1931 flamingo]

steve s: The metal cannister filter, top right, do you have a p/n, application, manuf for it?? Looks like the one on mine. Thanks.
Paul in CT

[Jim Boehmke]

Not sure if anyone mentioned this but on all my A's, I've always drilled the valve inlet hole over size and pressed in a short "stand pipe" sticking up 3/8" above the, inside, bottom of the tank.

[Kurt in NJ]

A good long trip of a few thousand miles emptying the stock bowl every night will clean out the system for a long time ---it was 10 years before anything reappeared in my car, you do need the proper screens and they have to fit properly ---trapping any particles that won't pass through the jets---I took the stand pipe out, had less problems without it

I once had a chevy step van I leased to a startup buisness, it had a "rust" problem and kept clogging the small filter at the carb inlet, I got tired of changing it, left it out and never had another problem for the rest of the term of the lease, the sock in the tank kept out anything too large to pass the jets