I both drilled the tank for the fuel cell bulkhead, and did the POR-15 rust treatment yesterday. I figured I would drill the tank first, since that way I didn't have to worry about any metal shavings from drilling being in the tank, and also this way if I screwed up drilling the tank I wouldn't waste the time and effort in treating the rust.
Drilling the tank went fine, and I am running the fuel line down the right side of the bike. I used a wood block to check, re-check and then check again that the place I was going to drill would be correct. Other than getting the inside of the tank drill hole nice and smooth, it was easy. I used the bit on the inside of the tank to slowly smooth out the burr that drilling the hole had made. Put the bit inside the tank, and then chuck the tip of the bit into the drill and SLOWELY use it to smooth things out.
Working on this tank is about the only time I can ever remember being glad I have little girl wrists. I can easily get my hand, and about half of my forearm into the tank. Before using the chemicals to get rid of the rust, I decided to try and get as much of it out using a scotch-bright pad I had in the shop. I was able to get the majority of the surface rust loosened up, and then vacuumed out.
I then took the tank into the house, and closed the door to the basement, since i knew the fumes wouldn't be something I wanted to spread all through the house.
The POR-15 is a three step process. The first step strips any varnish that may have built up in the tank, and removes a little bit of the rust. The next step gets rid of all the rust, and I was really impressed how clean the inside of the tank was by the time I was done with these two first steps.
The next thing to do is get the tank 100% dry. I started by using my heat gun to blow hot air in the tank to the point where the tank body would hot very warm, or slightly hot to the touch. I did that a few times, and then had another idea. I borrowed a small craft heat gun my wife has, and that one fit completely inside the tank. I was able to get this smaller heat gun in the tank, and still was able to reach in and rotate the heat gun inside the tank. I could feel cool air being sucked into the tank from one side, and the hot air coming out the other side, so I knew I wasn't just heating up air trapped inside the tank.
I used the heat gun inside the tank 4 or 5 times. Getting the tank heated up to the point I didn't want my hand in it anymore, and then letting it cool off for a few minutes, and then repeating the process.
The last step is to put the sealer in the tank. The sealer is like a thick paint which becomes VERY sticky as it starts to dry. You get a pint of the sealer, which is more than enough to cover the inside of the tank, but just barely enough to get it to flow over some of the high points in the tank to seal them. I found this part of the process the most difficult. After rolling, turning, flipping, and generally moving the tank in every way I could think of for about 30-40 minutes I had to get the excess sealer out. Not an easy thing to do.
I ended up letting the sealer pool in a front corner of the tank where i could easily see it, and then siphoned most of it out. Then I used the foam brush the came with the kit to get any left over sealer out so there were no drips or other areas that had thick spots of sealer.
The sealer now needs to dry for several days. I could use a hair dryer to force air through the tank, and speed up the process, and I might do that just to get some fresh air in the tank, but I wont be putting any gas in the tank until at least next weekend.
I should also note that during all of this I completely taped the tank to protect it two different times, and used duct tape to seal the screw and vent holes to make sure they didn't get any sealer in them.
