That would be a 90 degree crossflow.-----These motors are famous for broken piston rings.-----Do a compression test for future reference.----Post your numbers here.
Intake / bypass cover is on the starboard side.----No water there.-----You need to address this issue YESTERDAY !!----Water on the bearings will destroy the engine quickly.
Test this primer to see if is working !----Remove small hoses at the carburetors.----Fuel should come out with key pushed in and motor cranking.----Report exactly what you find.
No ----the primer valve " clicks " when it opens.----It does NOT function the same way as choke flappers.----Best learn how this primer works.----It will help you diagnose issues and boating will be more fun when you understand how things work.
Test I did years ago.-----Same boat , same afternoon ,same style stainless props, same motor 115 HP Evinrude.-------19 "--5800 RPM --54 MPH.---21"--5400 RPM --54 MPH.----23" ---4900 RPM --54 MPH.-------Speed of the boat did not change.