There is no fuel filter on the bike as they didnt come with on back then, but I am putting one on. When I originally looked at the bike the tank looked clean inside but hard to say what it looks like at the other end, I havnt seen anything in the carbs when I clean them. I just pull the bottom covers and pull the floats and float valves out an spray them with carb cleaner blow dry and reinstall. I will try the garden hose trick and look for the kreem sealer. How long does it take for the sealer to dry before I can resintall the pitcock and add gas?
Before I went to resealing my tank, I would consider flushing it (running it through with gasoline) with the petcock out a few times. Some even pour a package of bb's into the tank and swirl it around to loosen the debris.
Get one gas can full of gas, a bunch of coffee filters and a large aluminum roasting pan. Remove the gas tank. Fill the tank half-full of gas. Remove the petcock and cover the hole with a thumb or large cork. Shake the tank and drain the gas through the open petcock hole into the roasting pan. Repeat until either your gas can is empty, or your tank empties clear, or your roasting pan is getting full (whichever comes first). You can put several stacked coffee filters into the opening of the gas can (held in place by a rubber band around the opening) to filter the gas from the roasting pan back into the gas can so that you can continue flushing the gas tank.
If the tank is really bad, use some bb's in the tank when you are shaking the tank. It will hasten the removal of the crud in the tank. Once the tank empties with clear gas, you are done. Of course make sure all of the bb's are out.
Tank sealing has its own problems and should be use as the course of last resort. Try the cleaning route first. It is basically free and is easy.
Once the tank is draining clear, clean the petcock filter and reinstall it into the tank. Since your bike did not have a filter from the factory, get a small in-line fuel filter from your local auto parts store and install it between the petcock and the carb(s). Try to not add any major dips in the fuel path. Some is inevitable, but try to not have the fuel line get below the level of the fuel inlet on the carb(s). You should replace the fuel line between the petcock and the carb(s) anyways, so get a foot or so of new fuel line when you are at the parts store.
After that, try to keep the fuel tank full when you are not riding the bike. Get gas at quality filing stations that get the most fuel deliveries per week. The should ensure that you are getting fuel with as little water in it as possible. Also keeping your tank full is the best way to keep water out.
