With a tank that bad you should have it lined. There are a bunch of methods for doing this. Do some research on the subject. Rebuilding the petcock would be a good idea.
You have had a LOT of rust come from that tank. The rusting won't stop after a vinegar rinse. You will need to line it to make it stop.
Aluminum and vinegar are the best of friends, especially after sitting for while. That gray paste is probably the aluminum breaking down. So yes a new petcock would be a must to solve your problem.
Check with Mikesxs.net. The "newer" xs650 have the same 46mm spacing has the xs400s. But please double check me on that before ordering. I know mikesxs.net has a Canadian distributor also.
Humm there's a couple model on mikexs website. But they are all non vaccum. That doesn't matter !?! The only difference is that there will no more be a hose that goes to the carb to the top of the petcock right ? Also with a non vaccum i'll have to close the valve when i'm done with the bike ?
That is correct. You will have to make sure to cap off the intake barb. Also the reserve position might get in the way of the tank, if I remember correctly.
http://www.mikesxs.net/product/20-0019.html This is what I have on my 80 and 82 xs400. No issues with the reserve position and works great. Just remember to turn it off when done riding and turn it on before starting.![]()
You need to try The Works toilet bowl cleaner if it's available around you. Google search it, it works very well and I've had great success with it when I did my cb550 tank and the old metal tank on my cub cadet garden tractor. Make sure to neutralize with baking soda when done or it will keep rusting though.
When I first cleaned my tank out with vinigar I thought it looked great but after one ride my petcock was filled full of junk that didn't get clean. After using the works, it was near perfect on the inside