Water and Plumbing  
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Water Inlet 

The water inlet is let into the hull. The flange is flush with the surrounding hull. 

 The water intake grill is between two of the trailer bunks and not easily accessible for external water input. 

Intake and plumbing is shown here. 

The inside has a ball valve seacock leading to a T which connectors to a hose bib for incoming water on land as well as leading to a hose barb which then fits the hose to run to the sea strainer.

These parts are partially hidden by the stringer.

The valves are accessible from under the rear seat.


Sea Strainer

The sea strainer is mounted on a block under the rear cockpit. The block gives sufficient depth for the screws to hold it down. Some may view this piece as optional, but I would rather have weeds in here than inside the engine passages.

The Perko sea strainer shown is unable to take full house hose water pressure. This resulted in blowing the top off when testing the engine! The new top is much thicker and stronger.

This style sea strainer is particularly difficult to seal well. The large perimeter surface area erquires a fair amount of pressure top create an air tight seal. Putting some silicone grease on the gasket does help. If there are air leaks in the water intake plumbing (even very small), the engine will not get enough water resulting in either reduced performace or damage due to over-heating. The engine I used will go into RPM reduction mode (limiting to 2300 rpm and sounding like it can't get enough gas) if it senses low water pressure. There is no other indication to the operator as to what is going on!

Sea strainer with cracked top


Water connections to Engine

The water inlet to the engine is thought the heat exchangers. This connection is extremely hard to reach down next to the engine beds. It is best to connect the water inlet hose prior to installing the exhaust systems. Once the exhaust is in place, there is very little room to maneuver and the hose is very stiff and hard to push onto the heat exchanger inlet

Bilge Pump

The bilge pump is located at the rear of the engine as shown. The water outlet is located on the side of the hull as shown.  I did not use the cheap white plastic "bilge pump hose" but instead selected clear reinforced vinyl. It has better flexibility and crush resistance.

It may be better to locate the pump at the forward end of the engine. The rear of the engine is NOT the optimum point for collecting the water. The water still pools forward of the pump as it sucks air and runs to the stern when underway, laving the pump dry again.  Another project for later...

The pump is the yellow item under the water hose which leads form the sea strainer to the engine. Note the silver hose is now gone and replaced by a "proper" blower hose routing.

Speedometer pickup

The speedometer pickup is a small bronze fitting on the underside of the hull located near the leading edge of the strut. The hole faces forward. It operates as a pitot tube with the impinging water pressure being transmitted to the speedometer. It is then translated into mph. The fixed mounting does act as a good weed catcher. Alternatively you can use a pop-up type mounted on the transom.

Prior to installing, make sure that the passages are clear. Mine had been soldered shut when the nipple for the hose was installed at the factory. It had to be drilled out with a #56 drill bit. Of course this was discovered after we had been trying to get speed readings on the water. In troubleshooting, you can blow (pretty hard though) into the speedometer inlet to get it to read.

Next: Deck framing


This page last updated 02/01/2003                        2000-2003 Mark Bronkalla