10-4 on the noise...I like the chuff chuff! I think I'm good on the belt, it moves 3/4" with a firm push.
The leak is frustrating as there's no pressure involved. I'll try sanding all surfaces with emory and see if I can't get them to seal, they all look smooth though. Maybe retorquing a few times to work those copper gaskets. Otherwise I thought a thin layer of liquid gasket couldn't do any harm? Just enough to fill in any grooves or scratches.
Sounds like you're heading in the right direction. A little gasket sealer won't hurt, but be careful not to let any get in the tank. Just a little noe also, sometimes these copper gaskets can be over tightened and they havew a tendancy to crack and then you got a leak. Check to make sure the copper washer isn't cracked. As for tensioning of the belt. You have got to make sure it isn't to loose also. If it is to loose the belt will ride on top of the cogs and the belt will most definitely snap. I usually hand tighten until there isn't to much tension on the belt then tighten until it is firm. These are pretty strong belts, but if improperly tensioned, they will break. Did you get out for a ride with it yet??