Yes, there was only one o-ring in the stock valve that I found.
There is a TINY orifice to allow water to circulate...but it's like a .030" slot.....and it barely shows when fully closed. I had to readjust to get it to show when fully closed, as I still believe that you need some flow in the heater hoses to prevent cavitation....but I haven't had time to sit and stare at the water passages in the block and water pump....to figure this out.
I had a BAD experience with the 302 in the GOose because a previous mechanic hosed up the hoses for the heater.....! Bad thing happened when the water valves were closed.....
I don't care to have the same happen here!
In fact, I may just put an "H" in the two main hoses just to prevent this from occurring. Use 1/2" thru T's with a 1/4" or 3/8" down leg and connect the two with a short piece of hose.
This way, when the valve is completely clogged up with crap.....
the water can still circulate and get air bubbles out of the water pump.Ford used this sort of feature in their heater hoses up past the 429's and 460's and on.....
That's my thoughts for now on it.....
Steve