KVOM is correct. The dashpots are for quick shut off of the steam input valves. They have nothing to do with the exhaust. The exhaust is simple--it is simply rocked back and forth buy the eccentric train of rods, levers, wrist and more rods. It has nothing like the steam input which has a bunch of timing modifying mechanisms.Yes exactly. I speak about exhaust valves and only the closing. For the opening, it's clear.
It's a big mystery for me. Perhaps the dashpots help? But in that case by depression or vacuum?
I'm wondering if you can send a photo with your concerns marked out, that might give us the understanding of what you are having trouble with. I can understand having trouble with the steam INPUT as that has all those modifying elements.