Installation Of Through Hull Fitting; Water Strainer; Siphon Breaker (Air Vent); Exhaust System - Whisper Power GV4 Piccolo Installation Manual

2.8.4

Installation of through hull fitting

It is good practice for yachts to use a hull inlet fitting with an
integrated strainer (water scoop). For propulsion engines in
motorboats the water scoop is often mounted against the
sailing direction to induce more water intake for cooling.
SAILING DIRECTION
FLOW DIRECTION
SAILING DIRECTION
FLOW DIRECTION
Figure 7: Installing water intake
THIS SHOULD NOT BE DONE IN THE CASE OF A
GV4 Piccolo OR ANY OTHER GENVERTER! WHEN
SAILING AT HIGHER SPEEDS, WATER WILL BE
FORCED INTO THE INLET AND YOUR ENGINE WILL
OVERFLOW!
See Figure 7. On motorboats and on sailing boats the water
scoop for a GV4 Piccolo should be fitted with the opening faced
backwards to prevent water being forced in during sailing. Use
a sealant when mounting the skin fitting.
2.8.5

Water strainer

Use an appropriate water strainer with connections of 12.5 mm
(1/2"). Install the water strainer in a well accessible position,
(refer to Figure 6, ref 6) 5 cm above the waterline.
2.8.6

Siphon breaker (air vent)

When the point of water injection is below the waterline, then -
when the engine is stopped -there is a risk that the cooling
water may enter the engine as a result of siphoning. To avoid
this happening, the GV4 Piccolo is designed to accommodate a
siphon breaker (air vent). In the standard delivery of the GV4
Piccolo connections are bypassed. Hose of 12.5 mm (1/2") inner
diameter should be used.
If the GV-4 cannot be mounted such that the bottom of the GV-
4 is placed above the waterline, an air vent must be installed.
Extend the water hose of the by-pass 60 cm above waterline
and install an air vent. Ideally, the air vent should be mounted
EN / M-GV4 Piccolo for marine applications / May 2017
above the yacht keel centre line (i.e. to minimize the influence
of swaying on the water intake).
Fast motorboats will lay deeper when sailing at large speed
(non-planing) and have additional pressure on the water inlet.
This should be avoided to prevent water from entering into the
engine.
If the air vent is clogged the water hoses will not
be vented when the GV-4 has stopped and water
can be forced into the engine. this leads to
immediate engine problems and eventually
severe damage!
DAMAGE CAUSED BY THE INGRESS OF WATER IN
THE ENGINE IS NOT COVERED BY WARRANTY.
The siphon breaker that is delivered with the Whisper Power
siphon breaker installation kit does not require a connection for
a hose to drain the little water that could be spilled from the
valve. If you use another kind of siphon breaker that has a hose
connection, make sure that the drain should go downwards
down directly and that it may not end under water. Water must
flow out freely and air has to flow in freely as well (refer to
Figure 8).
Figure 8: Wrong siphon breaker hose routing (non-Whisper
Power siphon breaker)
Check the air vent at regular intervals. Open, clean and
lubricate the valve as required (Figure 8).
2.9

EXHAUST SYSTEM

Inter-cooling is almost always combined with a wet exhaust
system: Water is injected in the exhaust system of the
Genverter. In this way the cooling water that has passed the
heat exchanger is mixed with the exhaust gases. Temperature
and volume of the gases are thereby reduced considerably, so
that a rubber exhaust hose can be used and the level of noise is
reduced as well.
However a dry exhaust is possible dumping the water over
board separately.
Keel cooling is almost always combined with a dry exhaust.
ELECTRICAL INSTALLATION (12 VOLT)
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