Proper torque for double-tank manifold nuts?

[captain]

Remember the seats are made of brass, over working the seats by extreme tightening will cause the brass to harden and become harder, and the valve harder to get a seal over time, this will also cause the brass inserts to become brittle. So the least amount needed to get the job done is the best. Same principle as in reloading ammo and reusing brass. I have in the passed annealed seats that were removable from the valves to make the brass soft again, then reinstalled them. As I know some will try this, be careful , removal can be tricky and not ruin the seats. They screw in. The secret is using the correct fitting screw diver blade. It has to fit the slot in width and depth, be sure the end is flat and square, and the larger the handle the better. The slots are on the leading edge,take care, lightly tap the screw driver handle when it is in place, to help break loose the seat. As I remember I had to grind a large screw driver down to size, keep the tip cool as you grind, dip it in water often, don't mess up the heat treating . -------Ron

I think I maybe about learn something new because I have no idea what seats you are referring to

[TENNESSEE DIVER]

There were screw out brass fittings or seats that were inside the the double tank end pieces. The USD are solid and can be lapped to some degree to stop leaks, but does not always work.

[captain]

There were screw out brass fittings or seats that were inside the the double tank end pieces. The USD are solid and can be lapped to some degree to stop leaks, but does not always work.

I was aware of the screwed in seat on the J end of the maniflod to retain the J spring and seat but never noticed one on the opposite side.