TheSamba.com :: View topic - Plating or sealing the INSIDE of fuel lines

Wed Sep 11, 2013 7:33 am

Hi All,

I have a reoccurring problem of rust bits getting into the carbs (Zenith) on my '58 Cab. It seems I have to pull them twice a summer for a complete cleaning. When I pull the jet covers and drain into a white cup, I can always see small bits in there.

The tank is clean and there is a new-ish metal-can filter from the tunnel to the steel line going to the pump. The pump screen is clean. I have had the lines from the pump to the carbs off and they are a nice orange-rust color inside and when I stick a Q-tip in there, it comes out orange. I'm thinking it is the ethanol in the fuel carrying water, but, at any rate, I need to get them completely cleaned and I was thinking a good sealing or plating would do the trick.

Plating can be a bear because there needs to be a continual flow though the line. What I'm envisioning is a small spray nozzle on a long thin tube that can be pulled through the line evenly coating the inside with a gas safe sealant.

My fuel lines are original and un-cut so there is nothing between the pump and the carbs.

Other than the soft rust, they are clear and in great condition.

Would a good cleaning and maybe some phosphoric acid clean them enough that they won't rust in the future or is plating/sealing my only option?

Any ideas?

Thanks,

Franny

Wed Sep 11, 2013 11:29 am

Franny,

Much has been said about Ethanol even over here where pumps do not display the pecentage used in the fuel which up until last year was 5% but according to some going up to 10% this year. It would seem the ' super unleaded' over here generally does not include Ethanol at the moment but will later.

Ethanol because of the Oxygen content could cause rusting but also will super clean and release very old dirt from iside the system as well as affect as you probably know, rubber piping, cork, and many other materials used on older cars. I even read it can attack aluminium! It would seem aircraft are except from using it.

Is it possible what you are seeing is not rust but small pieces of rubber, the pump diaphragm ? the Zenith accelerator pump skirt? I don't know in the states exactly the percentage used in your gas? Does you 'super grade'
have it? I see your point about the piping but think maybe pressure cleaning the only way. How old is your short rubber piping from the tank petcock to the metal piping?

So far my non rubber piping is like yours original and I don't have any other filter installed. Its seems okay but I pay the extra and run with super unleaded.

The article attached is one of the best I have read and is worth reading.

http://www.groups.tr-register.co.uk/wessex/ethanol-update.html

Let us know what you decide or others if you have the solution. ( I read somewhere about a special fuel additive??)

Roy

Wed Sep 11, 2013 11:44 am

Thanks Roy,

The particles look to me to be too small for rubber bits. The fuel pump was recently re-built and the diaphragm is actually red. The rest of the bits in the carbs look fine when I disassemble. I suppose I should run a strong magnet next to them to be sure they are steel.

Our fuel here in Colorado is 10% across the board. I know alcohol has an affinity for water and can be dissolved in each other 100%. That is why I was thinking water, but you may be right in that it is just the oxidant property (which is one of the main reasons it is added I believe)

Everything else *should* be clean from the tunnel rearward assuming the filter there is doing its job.

I suppose I just want to remove the inside of the fuel lines as a possibility. Also, if they are rusting from the inside out, they won't last forever.

I have heard that adding 4oz of Marvel Mystery Oil to a full tank can help, but I haven't tried it...

I appreciate your thoughts :)

Franny

Wed Sep 11, 2013 1:38 pm

Hi Franny,
We have the same 10% ethanol plus whatever other CA mandated crap in our gas--probably the same or similar to what is required in Denver. Anyway, I haven't noticed that phenomenon with either of my cars. I have used MMO off and on. I have heard a lot of people swear by it. I know my dad used it in his Roadster oil back in the '60's-'70's and I think it had a lot to do with why the engine went so long without a rebuild, and it was his daily driver (50+ miles) for 15 years.
Good luck--
Jon

Wed Sep 11, 2013 4:40 pm

Franny

There is a Tractor Supply store not too far from you. They sell Evapo-Rust by the gallon. A very pourable liquid that is not aggressive. You could try removing the fuel lines to the carbs, plugging up one or more ends and fill them with Evapo-Rust for an overnight soak. Rinse out and see what they look like. After that, possibly one of the liquid rust converters could be poured in to put a more rust proof coating inside the lines. The first step should remove most or all current rust, if that is what it is. I have used this inside the oil fill pipe to de-rust and it worked very well. Have not tried the second step, as I coated the inside of the oil fill pipe with Glyptol. But that would be too thick for a fuel line, and possibly flake off.

An easier but more costly solution would be to buy new fuel lines from Stoddard if they carry them.

Phil Planck

Sun Sep 15, 2013 12:54 am

Morning Franny, whilst not addressing you problem per se, I can recommend the Camelbak line cleaning brush as a pretty effective tool for 'getting in there and having a poke about'

Regards, Mike

Tue Sep 17, 2013 8:36 am

Franny, glad you are safe from the nearby flooding.

For the lines, I generally use new, especially the long one that goes through the tunnel. A coil of appropriate sized brake line works well. If reusing old, I blast through them with glass beads to get any rust, then do as Phil recommended with either the relatively benign rust remover or the aggressive and dangerous acid.

Then, the hard part: coating the ID after plating the OD. What I have not tried is 'electroless nickel' but a plater would know what gets inside a long small tube.

I have had great results with a clear epoxy gas tank sealer from Caswell. It is viscous, but maybe thinning it somewhat would work if drained after many turns, rolls and flips to get an even coating while it kicks. That may be too restrictive, but.......then you'd get new lines...... :roll:

Seriously, that epoxy resists ethanol and 'old fashioned' gas (as you know, I like Avgas in a mix). What I also know is that ethanol is not the only issue here, as lines were rusting 'back in the day' before that concession to the corn industry accelerated the signs and resultant problems.

What's needed is a very fine, fine filter at the carb inlet, similar to what Weber designed or maybe a clear sediment bowl like early 4-cam cars had.....and most tractors.....with new lines from that to the carbs.