One big thing I wanted to take care of on the Peugeot while it was all apart was cleaning and sealing up the gas tank. It’s pretty rusty and the in-frame gas tank mopeds are a pain to do since there’s a lot of shaking and rotating of the tank involved.
So I got to work, here’s the method and products that I’ve settled on as my favorite. There are many other methods of taking this on, but this just what I like doing.
Stuff You’ll Need
- Aquarium Gravel
- Red Kote
- Something to plug the filler hole/petcock hole (plastic wrap,rubber bands, proper size bolt if your tank used an internal thread for it’s petcock)
- Baking Soda
So Red Kote is pretty amazing stuff, with most tanks sealants there’s an etching process you have to go through and then once you seal the tank the remainder of the sealant needs to be tossed. So with little moped tanks you’ll want to do a couple of tanks at once in order to get the most bang for your buck. With Red Kote it’s basicly just knock out the really loose shit, dump Red Kote into the tank, roll it around then dump the excess back into it’s container for later use. I do a little bit more to it though, just because it’s something I only want to do once and this is the time to do it.
1. For starters take you tank, empty it out, remove the petcock, etc. Stick a garden hose into the fuel inlet and flush the crap out of it.
2. Empty it out, seal the petcock hole with some duct tape or something. put a couple handfuls of aquarium gravel into the tank. I like to use aquarium gravel since it’s inexpensive and readily available at a lot of places locally.
3. Seal the filler hole and proceed to shake the living crap out of it. The more and longer you want to shake it the better, you can’t really overdue this step.
4. Unseal the tank and empty all the gravel and loose rust into the garbage. It might be tricky getting it all out if you fuel inlet extends into the tank, just keep bouncing the tank up and down until you down hear anything rattling around anymore.
5. Seal up the petcock hole if it uses external threads you can use plastic wrap and rubber bands, if it uses internal threads you can use a bolt that is the same thread size as your petock.
6. Fill your tank all the way up with vinegar, let it sit for a few days and if it’s really rusty a week. Vinegar is a lot slower than other methods, but it’s a lot easier to handle and dispose of.
7. Empty out the vinegar and flush it out with the garden hose again. dump in some baking soda and water, slosh it around. This will neutralize any remaining acidity from the vinegar. Flush it out with some more water.
Tank on the left is before, tank on the right is after. Still a couple of rust spots but the majority of the rust is gone
8. Let the tank sit for a day and dry
9. Dump a bunch of red kote in the tank, seal both petcock hole and filler tube with plastic wrap or something similar.
10. Roll the tank slowly, try to make sure every portion of the interior is coated.
11. Dump excess red kote back into it’s original container.
12. Let the tank/frame sit open for about a day or so
I still run a fuel filter on all my mopeds for good measure, but using the steps I’ve outlined above I haven’t had a single problem with rust and clogged carburetors.