Cleaning small gas tank

[TC Chris]

Advice, please. I need to clean residue out of a small steel outboard motor gas tank. I figured I'd buy some solvent at the hardware store and dump it in to sit for a while, but cannot recall which solvents work on gasoline residue. Suggestions? For the exterior, I'll try engine degreaser.

Chris Campbell

[Conelrad]

If the gunk is just on the bottom, putting some carb dip in and it will dissolve that right out in a day or two. It comes in a gallon can with a little basket inside. Chem-tool brand if I remember. Not much else will cut gasoline varnish.

Don't get any on you, and wash it out with water outdoors.

D

[electra225]

If there is a radiator shop around, or even a good machine shop, they can "hot tank" your gas tank and get the residue out.

[Conelrad]

True, but you'll lose all the external finish that way.

D

[TC Chris]

If there is a radiator shop around, or even a good machine shop, they can "hot tank" your gas tank and get the residue out.

I'm afraid "radiator shop"falls into the same category as "TV repair shop," which is to say, scarce as hen's teeth. Fixers of any kind are disappearing. When I had somebody replace the impeller on my little Merc outboard a couple years back, the shop owner lamented that when John, his outboard guy, retired there was nobody available to take his place.

Chris Campbell

[Firedome]

My rad shop guy died 3 years ago and the shop closed, last one around here.

I've replaced many an impeller myself, 2 years ago on my 50hp Johnson. Some older Mercs had them in the top of the leg right under the powerhead, a real pain, OMC always put them in the lower unit.

For cleaning out old 6 gallon outboard tanks lacquer thinner worked for me.

[TC Chris]

I've got the shop manual for the little 8 hp Merc and was going to replace the impeller myself--usually easy, right?--until I read their instructions. They made it sound like a week's project, full time, micrometer in hand. So I took it to the shop because I needed it done yesterday.

OMC and the other majors at least put long-lobed rubber impellers in their motors, unlike the little short ones used on so many inboard marine engines. Looks to me as though the engineers knew the little outboards would sit without the shaft rotating for extended periods and they needed impellers that could tolerate that. They last a very long time if you don't run them while dry. On the other hand, the short-lived inboard ones are faster ad easier to replace, so doing it often is not such a big pain.

Chris Campbell

[electra225]

When grandpa had his shop, they would put a handful of river gravel in the gas tank, then a gallon of lacquer thinner. Then shake the dickens out of it. I reckon they figured they'd be better off with a few pieces of gravel left in the gas tank than to fight with the varnish that would end up in the carburetor.