Anyone have one of these installed in a Dominator 12S pump?
Just where exactly did you drill the hole?
Need measurements.
Thanks
On the Dominator bowls, we drill them 2.500 inches back from the suction housing surface. That works out to be about 7.00 inches from the droop surface if you want to try to drill it while on the boat. That places the check valve at the largest inside diameter. The wall thickness of the Dominator bowl is just over 3/8” thick in this area.
On the Berkeley bowls, we drill it .250 inches back from the edge where the inside diameter of the suction housing register transitions to the largest inside diameter before the stator vanes.
It looks like your transom adaptor is way back on the bowl. Like GT said, drill it just behind your transom adaptor, which may be the limiting factor. It has to be located outside of the boat. If your transom adaptor causes you to drill further back, you could get into the stator vanes. If you accidentally drill into a stator vane, it will cause cavitation in this area.
Be careful of breaking through with the drill bit. The tap drill size for 1/4-18NPT is 7/16” and if not careful, could break through to a depth that could cause internal damage.
The threads on those check valves are pretty questionable. When you tap, don’t run the tap in too deep. General rule of thumb when tapping pipe threads is to leave 4 threads on the tap showing. If you tap that deep, the check valve might not tighten up. I would leave at least 6 threads showing on the tap and see if the check valve will start in. You can always run the tap in a little deeper if necessary (in 1/4-turn increments).
Good luck,
Joe
