Hi OB,
What I did was to open both holes, using a plumer camera and small tools I filled the seat post areas with steel wool and it wool then I filled with JD Weld until almost the opening.
It was easy. I already sealed it last night with Por 15, is better than the Creme thing. but first I sheck for licking for 2 days.
Originally given to me by ALSLANSMONKEY
"HI'm too tired to hunt down where the original(at least I think it's the original) post by HBLocal was on how to do this, but luckily for you I had a copy of it saved in my g-mail account so here it is...
first I disassemble the entire bike then wrap the frame twice with ten mil plastic to protect it from accidents.
I then drill the fill hole and the petcock hole where I would like them placed after that I tap the holes so I can install the valve and nipple I use for filling the tank do not install until after the tank has been sealed.
On the head tube you can use pieces of blue masking tape on your fingers and reach inside the head tube and cover the two holes from the inside the third hole you can only get to from inside of the tank your filler hole is how you get to it put a piece of tape on a screw driver or something small enough to fit into your filler hole and gently cover the hole it is very hard to see the hole use a flash light .
Once this is done hang the frame w/the head tube down you will need to go to pep boys and get some J.B. weld you will need the "INDUSTRO-PAC" take the J.B. weld and leave it in th sun for twenty minutes so it will heat up and become plyable then mix up half of the tubes and put in a small hypo-dermic injection tube and then fill up the inside of the tank w/ J.B. weld roll it slighly back and forth to complete cover the holes inside check for leaks let dry over night.
The hole in the seat tube is a little harder to do but I have done many and so can you again put a small piece of tape over the hole on the inside w/ your finger get some fine steel wool and twist into small rolls and insert into petcock hole try and get it to both sides arournd set post as the back of the wish bone on the frame is also not completely welded and will leak down to the rear axle hanger.
Use a small piece of hard wire or a bent screw driver to pack the steel wool in place very important that u spend some time doing this to insure that the J.B. weld you are going to inject does not leak thru to the bottom hanger.
Once this is done hang the frame w/the head tube up and again heat up the J.B. weld and inject from the petcock hole use a flash light to see how much u are injecting keep the J.B. weld about and 1/8" below the petcock threads and keep the threds clean .
Keep ckecking to see if the J.b. weld is at the level you left it if it goes down that means you have a leak thu the steel wool and you will have to re-pac if it does not go down then you have sealed the tank successfully and are ready for the next step,but before you move on do one final check by filling the tank w/water if it does not leak out or go down you are ready.
You will have to go to a motorcycle dealer and get some tank sealer called " CREME" it is a three step process which consists of degreaser acid wash and the actual sealer itself.
follow all instructions on how to use the sealer this is why you wrap the frame in plastic this stuff is very toxic and will ruin paint etc.when you are using the acid etch do not plug off the tank completely as this will cause the pressure to build and it will blow out all of the acid and you will have one big mess.
After you successfully gone thru all of the steps let it dry for one week before putting any fuel in the tank after that you will be ready to assemble the rest of the bike as for the filler tube on the top of the frame I use a threaded 1/2" brass nipple w/a cap on once this is installed I will paint on a thin line of J.B. weld around the nbottom of the threads to ensure there are no leaks there.
ere are the instructions on how to do it, the camera part was my idea.
