Fuel polishing worked
 

The crud in my tank took out my shutoff valve and my carb started leaking (with the float height set correctly). So, I got a new float valve and seat for the carb, shutoff valve, and decided to try polishing the fuel to avoid pulling the tank

I am ecstatic to report that it worked! No more junk in the tank and thankfully my tank wasn't really rusty inside. I guess it was just almost 100 years of gunk combined with sitting for decades before I got it

If you're thinking about trying it, it's worth a shot. I got a couple inline filters, a fuel/water separator with an R12t screw on filter, and an electric fuel pump off Amazon. Ran it off a 12v battery hooked to a charger set to 10a. Wired the pump to a relay and wired in a 20a inline fuse. Ran it for 4 hours and it was nice and clean. It's a lot easier than pulling the tank

Re: Fuel polishing worked
 

Sharp Tudor! Thanks for posting.

Re: Fuel polishing worked
 

Bandit, Please supply brands, and if possible, part numbers for the equipment you used. (Pumps, filters, separator, relay, fuse.) I don't need it but I suspect there are many on the Forum who do. I don't think people would have trouble finding a battery and charger.

Re: Fuel polishing worked
 

Fuel pump: https://www.amazon.com/gp/aw/d/B0C88...b_b_asin_title

R12t filter: https://www.amazon.com/gp/aw/d/B08J3...b_b_asin_title

I'm sorry I don't have any part #s for the rest of it. Everything else came from my box 'o junk I've collected over the years. But it's just a standard 12v relay and one of those cheap inline fuel filters

The cheap fuel filter sits before the r12t as a pre-filter. The r12t filter feeds into the fuel pump and the fuel pump returns back into the fuel tank

Fuel tank - inline filter - r12t - fuel pump - gas tank

For the relay it goes:
Control side:
12v+ - switch- relay terminal 86
Relay terminal 85 - ground

Load side:
12v+ - inline fuse - relay terminal 30
Relay terminal 87 - fuel pump +
Fuel pump negative - ground

Re: Fuel polishing worked
 

That's a great idea for rusty tanks!!!

Re: Fuel polishing worked
 

What about using something like this as part of the system? You would rig this funnel over the gas tank and then run a hose from underneath the tank, through a 12V pump, up to the funnel. Would that work? You could even pour in some solvents to dissolve crud.
https://www.amazon.com/Hopkins-F1NC-...dp/B00N4UN1RM/

Or I guess another way to do it would be to position the funnel under the tank outlet in the cabin, going into a gas can, and then you run the hose from the can up to the top of the tank via the pump. That way the pump is always flowing clean gas.

Re: Fuel polishing worked
 

I originally was looking at that F1NC, but from "Mr. Funnel". The one I was looking at would filter particles down to 50 microns. Which probably would've got most of the junk out. But, I chose the R12T one because it was rated down to 4 microns and I was picking up a really fine silty substance in my fuel bowl. The reason I ran the return line back into the tank is to help stir up the junk sitting at the bottom.

Using it in the tank outlet would probably be the way to go. Especially if you've got a lot of bigger chunks of junk down in there. Would help to keep the other filters from getting clogged up as fast. You'd just have to make sure you don't exceed the flow rate of tank outlet with the electric fuel pump

Re: Fuel polishing worked
 

Now that I'm thinking about it, I wonder if it would work to run the whole thing backwards. You have the F1NC sitting atop a bucket on the ground. A hose runs from the bucket, through a 12V pump, then through a 4-micron filter, then *up* into the tank outlet inside the cabin. You then have a second hose going down into the tank (remove the spark arrestor of course) with a hand squeezer on it to pull fuel up into the hose and set up a siphon effect; this hose routes down to the F1NC funnel.

The point of doing it this way is you can manually reposition the hose to suck up debris from various points in the bottom of the tank, and the tank outlet will stay clear of debris because it has a continuous jet coming out of it, which also serves to stir up the bottom of the tank.

Just an idea, I dunno if it would work in practice.

Re: Fuel polishing worked
 

Here's a pump that flows 120gph under 12V power, I bet it would flow a significant fraction of that under 6V power. So that's 1-2 gpm, which is probably about the fill rate you would get with a gravity siphon out of the top of the tank.
https://www.amazon.com/80W-Gasoline-...dp/B0CSN3QWKW/

Re: Fuel polishing worked
 

This sounds like a great idea, and one I had been thinking about for one of my 28 phaetons, although I was planning to have the gas drain into a jerry can and then repeatedly dump it back in.

But some of the posts also got me thinking about getting decades of sludge and rust scale out of the tank. I have an old parts air sprayer (in photo) that hooks to a compressor, and sucks solvent up through a hose by vacuum to spray it out under pressure. This seems like a good way to get some of the junk out of the tank more effectively. But of course I am very hesitant to spray gas with it! So my question is, what do you guys think about draining the gas from the tank, then repeatedly spraying non-flammable parts cleaning solvent into the tank until it is clean (or cleaner anyway). Then pour some gas into the tank a few times to get rid of any remaining solvent. Does this sound like a reasonable idea?


Thanks.