The water inlet is let into the hull. The flange is flush with the
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
These parts are partially hidden by the stringer.
The valves are accessible from under the rear seat.
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
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
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
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