Grungy gas tank

Thanks for the replys. The varnish is on the bottom and up the sides maybe an 1/8". The plastic insert is suspended off the bottom at least 3/8". I will take some measurements and see how far off the bottom the deep the pickup tube goes. I'm thinking maybe its not that bad. This engine is on a tiller that gets only occaisional use. If I drain the tank when I'm done using it, I could be ok. I got on youtube and found recomendations for acetone, laquer thinner, denatured alcohol, and Sea Foam. Tried all but the laquer thinner. Also tried some of the solvent in my 30 yo carb cleaner bucket. I did find some tiny 4-40 thread nuts. I'm tempted to throw in a solvent to soften everything, then the nuts and sit there for a while with a beer and swish it all around and see what comes out.
 
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StarTech said:
Regular Acetone can do a lot damage to both other metal items and you as it gases off when exposed to the moisture in the air. I have had tools damaged in the area where Acetone was being used. And also have had my breath taken away by the fumes. Acetone also has to be neutralized after it done its job with water. Any ferrous metal must treated with oil or it will flash rust. Also don't get the Acetone on any aluminum items as it dissolve them quickly which is why I use it to aluminum transfer on steel crankshafts.

Now they do make a low fumes version but quite a bit slower at cleaning and I do mean slower.

Acetone will damage that plastic insert.

As for the tank availability if it is the 3 quart one it has been NLA for quite sometime after it went over $100 cost for the dealers. The only two solutions available is a tank liner liquid and replacement of the engine. Tank liner can only fix the main part of the tank and not the fuel bowl cup directly under the carburetor.
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The plastic liner is likely nylon-12. Acetone is moderately agressive, and not recommended for prolonged contact. There is a gap at least 3/8" undet the insert, and I only put in about 1/8" acetone. I should be OK. The fuel bowl cup is clean.
 
Just some thoughts to kick around while you are swishing your cold beer.

Why not get rid of the plastic insert if it's just used as a baffle?

A rototiller does not need a gas tank baffle.
I've removed the foam baffle from those type tanks and tumble cleaned them, but I've never encountered one with a plastic baffle.
It's very doubtful if you will ever get it cleaned enough to be trouble free with 1/8 inch thick varnish with the baffle in place in areas you cannot even inspect. It's been my experience with a varnished tank that new gas starts breaking down the varnish which then is suspended in the new gas and glues the internals of carb and even fuel filters and draining out the gas and leaving varnish inside is kinda in the category of peeing into the wind and/or hunting for skunks underwater. The gas you are draining is not safe to use for another engine's use because it's contaminated once it's exposed to varnish..
If you cannot come up with a way to get rid of the plastic baffle just operate as is and in meantime keep a eye out for a Honda engine from a pressure washer. It's been my experience with those type tanks if it's the type that star tech mentioned that trying to find a GOOD rust free replacement is waste of time and new tank if found is $100 or more if found. Stay safe when using/breathing the solvents because you are playing with a small bomb also if spark or static spark happens.

Keep in mind even the varnish is explosive.

.
 
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Found my fiber optic proctiscope that I thought my son had pilfered. Looked in the tank and it was a lot cleaner than I thought. Couple of small rusty spots, a little grunge, but not bad. Opened up an old bottle of gel rust remover. The gel had separated from the acid. I poured off the acid and put it in the tank, swished it around, and let is sit. Poured it out, lots of grunge came with it, put in some baking soda and water, let it sit awhile, poured it out. Filled it with clean hot water and Totally Awesome, swished it around, let it sit, and poured it out. Compressed air, then WD-40, more swishing, poured it out. The proctoscope sez the tank is clean. So happy. Now I gotta get the wheels off the tiller so I can replace the oil seals. Trying to do this on the cheap. Doing this for a neighbor. He's old and broke and his garden is his only joy. Not sure if he believes I had all these B&S gaskets lying around, but when he presses me, I go get a couple beers. He is easily diverted. Anyway, thanks for all the help.
 
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Forest#2 said:
Just some thoughts to kick around while you are swishing your cold beer.

Why not get rid of the plastic insert if it's just used as a baffle?

A rototiller does not need a gas tank baffle.
I've removed the foam baffle from those type tanks and tumble cleaned them, but I've never encountered one with a plastic baffle.
It's very doubtful if you will ever get it cleaned enough to be trouble free with 1/8 inch thick varnish with the baffle in place in areas you cannot even inspect. It's been my experience with a varnished tank that new gas starts breaking down the varnish which then is suspended in the new gas and glues the internals of carb and even fuel filters and draining out the gas and leaving varnish inside is kinda in the category of peeing into the wind and/or hunting for skunks underwater. The gas you are draining is not safe to use for another engine's use because it's contaminated once it's exposed to varnish..
If you cannot come up with a way to get rid of the plastic baffle just operate as is and in meantime keep a eye out for a Honda engine from a pressure washer. It's been my experience with those type tanks if it's the type that star tech mentioned that trying to find a GOOD rust free replacement is waste of time and new tank if found is $100 or more if found. Stay safe when using/breathing the solvents because you are playing with a small bomb also if spark or static spark happens.

Keep in mind even the varnish is explosive.

.
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The varnish wasn't 1/8" inch thick. It was 1/8" up the side from the bottom. I thought about cutting out the baffle. Was looking at making an extended reach hot cutter for my soldering gun. Decided this was getting to be a little bit too much of a science project. Then I solved it with chemistry (see below). Better living through chemistry!!
 
I'm not sure what the plastic liner is - someone (above) posted that it's a 'splash guard' or baffle. Another person said it could be removed... I don't know. But, if you can get it out, here's a video from a guy who uses 'inventive' ways to clean grungy gas tanks. The tank is at the begining of the video.

YouTube... Barn Find Homemade tractor, could it be saved, pt 3 of 3
 
rickfischer51 said:
I have 5 hp B&S flathead on my a tiller. Gas tank is gummy, varnished, but no rust. There is a plastic insert in the tank. Never seen this before. I've tried all kinds of stuff to clean it. Laquer thinner, acetone, denatured alcohol, etc., even a bit of the solvent in my carb cleaner bucket. No joy. If I take it in to get it boiled out, what happens to the plastic thingie? I assume thats a baffle to produce sloshing. Anybody run into this before?
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Clean and rinse as best you can and run it. Use a Fuel Filter.
 
rickfischer51 said:
I have 5 hp B&S flathead on my a tiller. Gas tank is gummy, varnished, but no rust. There is a plastic insert in the tank. Never seen this before. I've tried all kinds of stuff to clean it. Laquer thinner, acetone, denatured alcohol, etc., even a bit of the solvent in my carb cleaner bucket. No joy. If I take it in to get it boiled out, what happens to the plastic thingie? I assume thats a baffle to produce sloshing. Anybody run into this before?
Click to expand...
The best I have seen is muratic acid for an acid it's on the mild end but use caution in using it.
 
g-man57 said:
I'm not sure what the plastic liner is - someone (above) posted that it's a 'splash guard' or baffle. Another person said it could be removed... I don't know. But, if you can get it out, here's a video from a guy who uses 'inventive' ways to clean grungy gas tanks. The tank is at the begining of the video.

YouTube... Barn Find Homemade tractor, could it be saved, pt 3 of 3
Click to expand...

I've been doing that type tumbling for several years, all sizes of mostly gas tanks. (tanks that are NLA or very costly). I've got a tractor with a 3ft diameter rear tires so I can tumble really slow. If they have pin holes I use Red Kote. Really surprised at some of the old tanks how shiny they get inside due to them using really good metal, and no coating required.
If it's a big tank I use porch chain, it really cuts good. Some large tanks have a slosh baffle inside that separates the tank ends and I cut a temporary entrance hole for the chain or nut bolts to clean the other side of the baffle area good and seal the entrance when done. When doing a large tank that has a baffle I do not use porch chain, I just use small nuts and bolts because the porch chain pieces might hang up on the internal baffle and the chain cannot be easily retrieved.
I pad the tank good and strap it to the tractor tire and slow tumble. Can go do other things. I sometimes tumble a really bad one for 4 hours or more.

Have to really be careful and have the tumbling machine wheels chocked good so as to not get into a run-away with the vec and some vec's will require both rear wheel be elevated. (traction will shift to the opposite wheel)

Using this procedure makes the major part of the cleaning more user friendly and does a better job than just manually cleaning and shaking the tank plus you can go do other things while it's tumbling.
I just use water and on final rinse I might use a solvent like little bit of lacq thinner for final tumble rinse so as the tank will dry faster on the inside using a fan or heat lamp when drying.

Not a fun job even using this procedure.
 
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If you have a radiator shop in your area they can probably boil it out for you. Radiator shops used to be quite common, now not so much. You could also try furniture restoration shops which dip furniture to remove paint, varnish ect.. You may also be able to find an engine or racing shop that can boil it out. Most of these hot tanks have disappeared because of the EPA. Your tank probably used to have a sponge in it and the plastic thing supported the sponge, just get rid of it. I guess you could also try to put it in an oven but you will never want to cook in it again. You will also run into opposition from your wife or mommy and they would be right. Of course if you try heat do not forget that the tank is soldered together and you can't get it very hot. Now I have found that normally, best way to clean tanks is to just leave them in the sun for a few days and then blow them out with compressed air........PS I just noticed the post above mine mentioned Red Cote. It is a great product that may even encapsulate whatever is in your tank. Follow all directions closely.
 
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