Removing paint from INSIDE a gas tank??

[JoeW]

I client just dropped of the nicest looking 1952 Lambretta 125c. The only problem is, it won't start. He just bought it and couldn't get it to run. I found good spark and compression but no fuel. I removed the gas tank and found the fuel valve filled with paint chips. It looks like someone panted the inside of the tank. It's coming off in sheets. I'm looking for ideas on removing the paint inside without damaging the paint outside. What do you have?

[Perazzimx14]

Are you sure it isn't tank liner peeling off?

[Groover]

Nice - post some pics of that baby. That is old one. I'm after a '57 or '58 (pretty much the same style). The tank was likely oily from the 2-stroke mix, so makes sense the paint it flaking off. Some of the paint/factory overspray came off on my G5 after using Evapo-Rust. I know it's safe on paint, but it still "loosened up" the light overspray that was inside the tank. I had to however use something to sort of scrape it off.

I'd suggest white wine vinegar, but it messed up the lining on one of my tanks. I had it in there for a week however. If only for 24 hours I'd say it might work in removing the paint but not mess-up the liner.

Those are suggestions and my experiences. Maybe someone else can pitch in with the magic bullet.

Edit: Also, if you do use vinegar, be sure to remove the fuel tap. If Vinegar and Antimony-Aluminum alloys get in the ring together, Vinegar will eat it's head off....

[JoeW]

Are you sure it isn't tank liner peeling off?

If it's liner it's a crappy one, it's very thin. Usually liner is thick like epoxy.

[atavar]

Assuming a metal tank... if this is a plastic tank stop reading.

The guys I have known to have success removing liner from gas tanks have done it with marbles or ball bearings and/or short drywall screws.  Dump a few handfuls in there and shake till your arms fall off.  Rinse with solvent. 
Rinse lather repeat until done.

I have heard of people using sand and gravel but that would give me nightmares of gremlins for years to come.

I am sure there are shops with expert blasters who can do the job for you.
T'were this my bike I would put external filters inline until the job was proven done, just in case. 

Now think of how much work this will be and price a new gas tank..

[twhitaker]

Wrap the above method in a couple towels and secure well then put in dryer. Set on no heat / fluff.
 

[Triple Jim]

Kreem is known for being a thin, white coating that comes out and messing things up.  Acetone will remove it if the stuff you're seeing is Kreem.

[dsrdave]

Diesel fuel and sheetrock screws.   Put them both in and shake, rattle, and roll.  Dump it out and rinse the $#*& out it.

[Antietam Classic Cycle]

I got most of a failed POR-15 liner job out of a customer's Ambo tank with MEK. Only used a gallon, turned the tank to a new position every few hours. It's really the vapor that does the job. But, there was still a few patches that had adhered well, those I removed by putting a pound of short drywall screws in the tank, wrapping it in bubble wrap, then a moving blanket and stuffing the whole wad into the dryer. Tumbling on fluff for an hour removed the last remnants and prepped the tank perfectly for Caswell Epoxy Gas Tank Sealer.

[Chuck in Indiana]

^^^^^^^^^^ 

[Cam3512]

I sent a nasty Suzuki Bearcat tank to a radiator shop.  They blasted the inside clean, then put a nice red liner inside.  Not all will do that, but ask around.

[tpeever]

I client just dropped of the nicest looking 1952 Lambretta 125c. The only problem is, it won't start. He just bought it and couldn't get it to run. I found good spark and compression but no fuel. I removed the gas tank and found the fuel valve filled with paint chips. It looks like someone panted the inside of the tank. It's coming off in sheets. I'm looking for ideas on removing the paint inside without damaging the paint outside. What do you have?

Acetone might work but you have to be really careful pouring it out so as not to damage the paint on the exterior of the tank. Same goes for most of the other solvents mentioned above. I presume the tank exterior is in nice shape and you are not planning to repaint? You could wrap the tank in shrink wrap to protect it.

[Chuck in Indiana]

3 coats of really heavily applied paste wax will protect the paint, too..