Fuel Tank Refurb

Define “never.”
Never used means it’s clean.
If never doesn’t really mean “never”, does it smell like gas. Does it pump any gas out? Does the pump work? Have you tried?
I wouldn’t even consider dropping the tank unless it was deemed necessary which is highly unlikely.
You need to be more specific as to the issue with it. Rvnetters are pretending it’s a 60 year old tank in a Studebaker!

If pump works IE makes noise, dump in 5 gal and pump it back out after sloshing around and see what comes out.
If you have a generator it has a inline filter. Keep a spare in case it plugs up.

Pump it out and see what the fuel looks like. The pump will probably fail the first time you use it if it sat with ethanol fuel in it. If you see brown rusty watery liquid then you want to drop the tank. Does the fuel station even work? If it had the 10% ethanol blended gas it may be a mess in there.

I don't think my fuel station has ever been used, but my generator uses the tank too. I ride street bikes so gas stations fill those. Those plastic pump guts have to be ethanol resistant. The biggest issue is having water in the fuel, that will rust out metal tanks. Some trailers do have plastic fuel tanks, I owned a KZ with one. But, my current trailer has a metal tank and I'm thinking about dropping it soon. I'm smelling gas fumes too much when its full.

I would first try an inspection camera. Maybe it's in good shape and won't need that much cleaning.

glennemay wrote:
These are definitely some great suggestions.

;) I guess I Was hoping for non removal of the tank. The camper is insulated and the tank is up in the underbelly. I am assuming you all are correct in the sense that it does have to come out in order to be completely cleaned and made useable.

If you can't get it out but can get access to the pickup fitting, you could build a simple fuel polisher. Not as good as full removal but I have used it with success on a boat we bought that had about 1/2 gal of water in the tank.

Buy a water separating funnel:
https://www.amazon.com/Mr-Funnel-AF3CB-Fuel-Filter/dp/B000SOIRCG/ref=sr_1_2?dchild=1&keywords=water+separator+funnel&qid=1622643982&sr=8-2

Rig up a hose so the funnel feeds back into the tank. Then pump into the filter. If you can fit an inline fuel filter downstream of the funnel that would be good.

The only trick is on the boat, the fuel pump I used was low volume, so once I set it up and secured the funnel in place, I just let it run for a couple hours, checking the funnel occasionally for water and dumping. I'm guessing the fuel station pump on the trailer will be higher volume, so you will have to be careful not to overload the funnel. Once you are comfortable that the water is out, you could remove the funnel and connect directly to the inline filter. No matter what, you probably want to keep an eye on the system so it doesn't dump 20gal of fuel on the ground.

These are definitely some great suggestions.

;) I guess I Was hoping for non removal of the tank. The camper is insulated and the tank is up in the underbelly. I am assuming you all are correct in the sense that it does have to come out in order to be completely cleaned and made useable.

If you can remove it without making it a big project:
- Drain
- Add water and a strong degreaser (such as dish soap). Slosh around and drain.
- Observe the inside with a flashlight to see if there is still crud and repeat.
- I've known people who insert a power washer wand to help get the tough stuff.
- Drain and let fully dry.
- Reinstall

…. I’d look for a well equipped Radiator Shop in your area to check it out and advise; sealing a fuel tank takes a lot of work to clean PROPERLY prior to coating the inside if’s you don’t want the coating to peal off in the future. And a properly placed drain flange on the fuel tank will make draining excess coating from the tank easier… Maybe UTUBE can help? I’ve done a few thousand fuel tanks in my life…

The BEST solution is to remove the tank, place a couple of handfuls of clean gravel in it, some diesel/kerosene, plug all the holes and roll it around on the grass. Drain, remove the gravel, add soap and water and repeat.

Last rinse well with clean water and leave in the sun (or use a heater) to dry it thoroughly. There are several products on the market to seal fuel tanks from the inside.