What a vintage 90’s fuel tank looks like on the inside

[N14ND]

This is my right fuel tank. I did my left fuel tank 6 yrs ago. It looked the same. Slosh or whatever they used pealed off in sheets and the fiberglass work was/is sub-par. I used Jeffco 9700, now called Rhino 9700 as the sealer. It is what the Ez/Cozy/Glasair/Lancairs use in their tanks. The top came off surprisingly easy. Now it’s time to clean everything up.
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[N14ND]

Started to clean out old slosh. All I have used so far is compressed air and an old gift certificate card cut in half to use as a scrapper. Doesn’t take much as the air alone lifts the slosh off. I can see why the top came off so easy as the slosh was sprayed into the tank attempting to coat it and the top was glued on with polyester resin which went right over the slosh. Not a good bond.

[109JB]

I'm watching. I'm seriously giving thought to doing this on my project Kitfox IV. Do you know if the Jeffco 9700 is good for use with auto gas containing 10% ethanol?

[N14ND]

Jeffco 9700 (now Rhino 9700) was formulated to paint/coat the inside of underground fuel tanks, as well as their go to coating for hangar and industrial floors. I chose it specially for use with auto gas or Mogas. Before I chose it I did an extensive search on the different composite aircraft forum sites, as well as individual builders sites. While you won’t get anything specific from the manufacturer, I think it is the best product out there. It does require sanding the surface and applying two coats, so you can’t use it as a slosh. PM me when you are ready. I have a lot of info.

[alexM]

Jeffco 9700 (now Rhino 9700) was formulated to paint/coat the inside of underground fuel tanks, as well as their go to coating for hangar and industrial floors. I chose it specially for use with auto gas or Mogas. Before I chose it I did an extensive search on the different composite aircraft forum sites, as well as individual builders sites. While you won’t get anything specific from the manufacturer, I think it is the best product out there. It does require sanding the surface and applying two coats, so you can’t use it as a slosh. PM me when you are ready. I have a lot of info.

What are you going to do to reskin the tops? I'm assuming the old ones were destroyed in removal?

[N14ND]

I made new lid/tops. I wrote down the fuel cap location for installation later and then cut out the cap and clamped a piece of 1/8” hardboard melamine over the top (white smooth side next to lid) with 4” on each side of the tank and marked the melamine with tank reference lines and made some curved supports and bondo’d them in place to hold the shape. And added a couple other supports to give it rigidity. Laid it on a table and draped it with thin painters plastic, peel ply and a wet lay up of 4plys bid cloth 7725, another layer of peel ply over the top of the epoxy resin cloth. Made two.

[N14ND]

Here’s a pic of my top.
Just an FYI for everyone. You can repair polyester resin fiberglass parts with epoxy resin components. You can’t repair an epoxy part with polyester resin. Epoxy doesn’t shrink, more stable and better chemical resistance. There’s lots of epoxy products out there. I have used just about everything. West, Poly Poxy, A/O, Pro Glas, Aeropoxy, just name a few.

This current tank will need more repair work than my first tank. The bottom appears to have only one ply of glass cloth. And all the fitting bosses will have to be redone as they had voids in the npt threads. I think I would have fought leaks with this tank forever.

The remaining slosh material is coming up with a heat gun and light scraping with a tiny screw driver. 26296

[N14ND]

Cleaned all the gunk out the fuel tank. Used a heat gun set at 200° and a plastic scraper to get the last little bits up. Started to clean up the baffles as they need some work. The fitting bosses (drain, fuel pickup, vent and sight gauges) are getting a total remake.
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[N14ND]

Here's a couple of pictures I found when I layed up the fuel tank lids a few years ago.


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