[Henry Schmidt]

We machine the through bolt sealing surface and add a chamfer as needed.
We only use Viton o-rings for starters. Throw away the blue silicon o-rings.
The o-ring is slathered with Dow 55 o-ring lubricant and carefully installed over the threads with a guide tool. The threads are then coated with anti-seize to insure an accurate torque. The added benefit of the anti-seize is that the washers won't spin.
The o-ring lubricant has an added benefit of Seal Swell. At 180 degrees the o-ring expands creating an enhance seal.