Went to change the power valve in my Proform 850 carb and it has a o ring. I'm used to the holley stuff that uses a gasket. Does the Proform only use a o-ring? Can a gasket be used in place of the o-ring? This style is new to me, so just trying to learn the do's and don't's.

An O-ring should have a counter sink in the metering block to retain it and keep it from squeezing out of place. I would use an O-ring over if it's not damaged. There are also plastic/nylon gaskets available that can be reused. I would think they would not be interchangeable due to the metering block. Just have to look at it.

The o-ring is counter sunk into the metering block. Just never saw this before so was curious.

I toss those and use Superformance standard round gaskets coated w/a bit of oil.......

Thanks Dom, didn't know if the "normal" gaskets work, but you just answered that question.