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Here's a fantastic technical drawing of the Dynafoil's cooling system:
The system takes in water via a screened vent in the bottom of the rear strut housing.  The water flows up a tube in the hollow rear strut and then enters the bottom of the hull via the hollow pivot pin that the rear strut hinges on.  It travels through a clear PVC pipe to an engine driven water pump that is mounted on the driveshaft, just in front of the PTO gear box.  The water pump pumps the water up to the top of the water cooled exhaust manifold.  The water then exits the manifold and enters the engine where the engine's own belt driven water pump pushes the water on throughout the engine.  The water then exits at the cylinder head and enters the muffler where it leaves the hull via the exhaust system.
IMPORTANT NOTE:  Water can not be drawn into the engine unless the rear strut is down in the water!  Do not run the engine with the rear strut raise, unless you have an outboard motor flush fitting attached and hooked up to a garden hose with running water.  Even sitting in the lake, with the rear strut raised the engine can not suck in cooling water!

The Dynafoil's Cooling System
Quite an amazing bit of engineering

Here's the part numbers for replacement coolant hoses from your local NAPA auto parts store:
Exhaust Manifold to Engine Water Pump top fitting:  #7741
Cylinder Head Outlet to Wet Muffler:  #7768
These come pre-bent and with a small amout of trimming fit exactly, and look perfect.  They run about $20ea.