Relying on memory of about 30 years ago, there is a curved copper water tube exiting the bottom of the powerhead. In one of the elbow fittings (I believe the lower one), there is a small squirt hole. Hard to see the hole unless you look. But when it is running there will be a strong squirt at a downward / aft angle from it. Spin it around for reverse, and it will pee in the boat.