Paint stripper to Clean Fuel Tanks?

[vbmlows]

I have two 150 gallon aluminum tanks in my boat that seem to have crud/varnish built up from lack of use by the previous owner. The tanks were empty when I bought the boat and had been that way for who knows how long. Running down the tanks fouls the carbs in my 1992 Yam 250 TXRQs every time and I'm spending way too much time cleaning carbs after every fishing trip due to loss of power. This keeps happening even with the use of Stabil to keep the gas fresh. I also only use regular gas (no ethanol) but the previous owner most likely used E-10.

The gas from the tanks to my engines is a darkish pink color even though the fresh gas that I put in the tanks is water-white. The engines run OK with clean carbs for several hours but by the end of a daylong trip, they suffer power loss and I have to limp home at subplaning speed.

I guess if I keep filling and emptying the tank often enough with ethanol-free gas, it will eventually clean itself, if I live long enough. Only problem is all the work required to keep cleaning the carbs and fuel hoses, etc. after each use, and running the risk of engine damage from running lean when the carbs get fouled 20 miles offshore. With a pair of V6s, there are a total of 12 carbs that need to be cleaned each time. Talk about a royal pain! Not to mention safety issue when fishing offshore with fouled carbs.

Seems to me I need to address the root of my problem directly: fouled fuel tanks.

After reading a lot of posts on stale gas, carb cleaning, etc. I started wondering if anyone has tried using a paint stripping chemical like methylene chloride to backflush the fuel system in-place, with the boat in the water. The way I am thinking this could be done is by mixing methylene chloride in some ratio (say 50/50) with fresh gasoline in a 5-gallon tank, reversing the primer ball and using it to pump the mixture backwards through the fuel filter and the rest of the fuel system back into the tanks, let it sit overnight, then pump the mess back out and dispose of it properly. Repeat the process until the stuff coming out of the tanks looks like fresh gasoline, then fill the tanks with 300 gallons of fresh gas and go fishing.

I am considering methylene chloride only because it is non-flammable, therefore safer to handle for a klutz like me. I could just as easily use methyl ethyl ketone (MEK) or acetone or some combination, but they are flammable.

Mixing the methylene chloride with gasoline is just so I won't have to use as much of it.

Has anyone had any luck doing this or some variation of this approach to clean up a fuel tank in place?

 

[waffles1]

Re: Paint stripper to Clean Fuel Tanks?

I work for a company that makes paint/baseboard stripper with methylene chloride and I would recommend not using it to clean your fuel tanks. They are designed to soften the paint to scrape it away. I think this would also play hell with the gaskets in your fuel system. Your problems would increase twice fold. I hate to say this but I would yank those tanks out and replace them. It's just not worth all the trouble they are causing. I believe you'll be having issues like this forever as long as they remain in the boat. There maybe a cleaner you could put in there that would desolve the gunk and varnish but I would never run that through my motor. You'd still have to pull them out, soak them for a long time and drain the gas for waste and probably do it another time. As I said before, I'd just replace them for piece of mind and be done with it. No more worries. Good Luck.

 

[Bob_VT]

Re: Paint stripper to Clean Fuel Tanks?

some of the problems are due to the ethanol in the gas........ it has a great benefit/side effect.....the ethanol cleans the tanks. If you can remove the tanks and clean them that might help.... I would NOT use paint stripper.

Install an extra filter or two and carry a few along. Filters are easier to change then rebuilding the carbs.

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

some of the problems are due to the ethanol in the gas........ it has a great benefit/side effect.....the ethanol cleans the tanks. If you can remove the tanks and clean them that might help.... I would NOT use paint stripper.

Install an extra filter or two and carry a few along. Filters are easier to change then rebuilding the carbs.

Thank you for the quick responses guys.

I like the idea of changing out the Racor filters, I can do that every half tank and see if that will keep the carbs from fouling out. Sure would be easier than replacing both fuel tanks, not to mention less expensive.

Not to beat a dead seahorse, but what would you use in place of paint stripper to clean the tanks if you were foolish enough to try it?

 

[99yam40]

Re: Paint stripper to Clean Fuel Tanks?

I do not know if you have accsess to the tops of the tanks, but if you do, you could pull the sending units or other openings and punp out all fuel and mop up everything out of the tanks. Steam cleaning after that if possible and then drying completly before puting back in service.

 

[robert graham]

Re: Paint stripper to Clean Fuel Tanks?

Maybe drain both tanks, fill one tank with a strong detergent, use a pump to circulate that "cleaning detergent" through one tank and into the other tank and back again. Let this mixture circulate for a day or so through both tanks to thoroughly clean the insides of tanks. You need to be able to see inside the tanks to be certain they're clean and to be able to drain the tanks completely. We used to use a method similar to this to clean steam boilers. I believe a product like trisodium phosphate might work, but as long as it's an alkaline detergent and not anything acidic which would attack the aluminum. You can do this but you'll need a pump(maybe Northern Tools) and check with an industrial chemical supplier on the best detergent to use. And of course afterward the water/fuel seperators will be vital. Good Luck!

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

Thanks to all of you for taking the time and effort to post advice and suggestions!

This weekend, I plan to open up and clean the insides of the tanks as much as possible with the tools available to me. My senders can be accessed by popping out the round deckplates located above them. The boat was also designed to allow complete access to both tanks by unscrewing and removing the fiberglass deck.

Googling the internet this morning, I also came across mentions of Star-Tron and PRI-G to treat dirty fuel tanks that goes something like this:
1. treat the old fuel with PRI-G to renew it or simply get rid of the old fuel and replace with fresh fuel
2. treat the fresh fuel in the tank with Star-Tron fuel tank cleaner,
3. let it sit for a couple of days in the tank,
4. go fishing to run off the fuel while changing out fuel filters frequently,
5. repeat above steps until carbs stop fouling.
The above procedure has the major advantage of allowing me to clean the tanks while fishing.

I also noticed that iBoats sells "Full Throttle Marine Fuel Treatment" that is supposed to both clean fuel systems and stabilize fuel.

Anyone had any luck with any of the above fuel treatment products?

 

[robert graham]

Re: Paint stripper to Clean Fuel Tanks?

Well it all just depends on how much junk is on the insides of your tanks. The stuff could just continue to break loose and fowl your filters and fuel system but it's worth a try. It would be really nice to be able to see inside the tanks so you'd know what you're dealing with. Maybe one of those fiber optic scope lights for looking inside engines. SCUBA shops have these for inspecting the insides of air tanks for corrosion or flaws. Maybe one of those guys would let you use his scope for your tank. Good Luck!

 

[waffles1]

Re: Paint stripper to Clean Fuel Tanks?

Just make sure any equipment you use is explosion proof. I hope you can get them clean but I just have a bad feeling. Good Luck.

 

[robert graham]

Re: Paint stripper to Clean Fuel Tanks?

Yep, I wasn't gonna say it, but me too! If it was me, I'd drain those tanks, flush them out clean and put an end to the problem. That's the nice thing about above deck portable fuel tanks. But good luck!

 

[dingbat]

Re: Paint stripper to Clean Fuel Tanks?

I take it you don't have a set of Racor's on the boat. Otherwise you wouldn't be cleaning carb all the time since the filter would have caught anything that came loose in the fuel system.

First step to resolve the issue is to replace all the hoses from the fuel tank to the carbs.

The next step is to install 10um Racor filters on each of the feed lines. Buy a couple of extra filters for each filter assembly.

If you have E-10 fuel available use that as your tank cleaner. E-10 cleans better than anything else on the market. If no e-10, pour in an adequate amounts of Startron tank cleaner and run it.

You may clog up a filter or two the first tank of fuel but after that you should be good to go

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

Bob and Waffy,

Thanks for the sensible safety advice. I'll take special care to not have any spark creating device or source of static electricity anywhere nearby when I perform the tank cleaning. Even though it will be slow and a little painful, the primer bulb and a manual positive displacement bilge pump is all I plan to use to move gasoline and solvents around.

Now that you mention it, you have even made me consider purging the tank with an inert gas like nitrogen or CO2, but I think not due to the risk of lowering the oxygen level in the cockpit workspace, as well as potential corrosion issues in the case of CO2.

As someone else said today, what a great site!!

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

I take it you don't have a set of Racor's on the boat. Otherwise you wouldn't be cleaning carb all the time since the filter would have caught anything that came loose in the fuel system.

First step to resolve the issue is to replace all the hoses from the fuel tank to the carbs.

The next step is to install 10um Racor filters on each of the feed lines. Buy a couple of extra filters for each filter assembly.

If you have E-10 fuel available use that as your tank cleaner. E-10 cleans better than anything else on the market. If no e-10, pour in an adequate amounts of Startron tank cleaner and run it.

You may clog up a filter or two the first tank of fuel but after that you should be good to go

Whoa Ding, I hadn't even read your post before replying to the earlier ones.

There is no E-10 at my location. A mixed blessing I guess.

I do have a pair of Racors, one for each engine and keep a number of Racor 3213 filter elements on board, thanks to the advice of other iBoats threads . I have needed them too, especially after I first got the boat when the fuel tanks were so badly fouled the Racors would plug up in an hour or less at WOT and starve the engines. However, the gummy stuff is still passing through and fouling the carbs even with the Racors. I'm not sure if that's because I'm waiting too long to change them out or because the filter elements are simply not fine enough to remove all the fine gummy crud.

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

BTW, the 3213s are 10 micron filters.

 

[dingbat]

Re: Paint stripper to Clean Fuel Tanks?

Whoa Ding, I hadn't even read your post before replying to the earlier ones.

There is no E-10 at my location. A mixed blessing I guess.

I do have a pair of Racors, one for each engine and keep a number of Racor 3213 filter elements on board, thanks to the advice of other iBoats threads . I have needed them too, especially after I first got the boat when the fuel tanks were so badly fouled the Racors would plug up in an hour or less at WOT and starve the engines. However, the gummy stuff is still passing through and fouling the carbs even with the Racors. I'm not sure if that's because I'm waiting too long to change them out or because the filter elements are simply not fine enough to remove all the fine gummy crud.

Nothing is getting thru a 10um filter. They will plug long before they pass anything.

Suspect your hoses are breaking down. When was the last time they where changed? If orginal and the PO was running E-10 you can count on them being in bad shape

BTW: What year and brand motor?

 

[vbmlows]

Re: Paint stripper to Clean Fuel Tanks?

Good point about the hoses. I'll have them replaced downstream of the Racors this weekend and a new set of filters too for good measure. Engines are 92 Yam 250 TXRQs.