MJM Yachts 34z Express - Manual (Page 25)

CHAPTER 6 ELECTRICAL SYSTEM
- 25 - 34z
6.5 ELECTROLYSIS & GALVANIC CORROSION
Metallic fittings that are exposed to saltwater
are subject to electrolysis and galvanic
corrosion. To minimize potential damage, your
boat is fitted with a sacrificial zinc at the
transom. This zinc is connected to the bonding
system of your boat. It should be visually
inspected whenever possible and replaced
when 1/2 of the zinc has been eroded. Pay
special attention to its condition when in new
waters and marinas, as environmental
conditions affect the rate of deterioration. If the
zinc erodes rapidly, current meters can be
used to assess possible causes and
remedies.
See Section 3.4, there are 5 engine zincs to monitor frequently as well.
6.6 BONDING
The bonding system of your boat connects all underwater metallic fittings to the sacrificial zinc
and the boat’s negative bus bar. In order for the zinc to protect an underwater part, the
connection must be clean and secure. The green wires that make up this system are not normally
current carrying.
6.7 ELECTRICAL
SAFETY
Please read and understand the important safety precautions included in the included NMMA
publication “Sportfish, Cruisers, Yachts – Owner’s Manual” concerning electrical safety.
6.8 GENERATOR
OPERATION (Optional Westerbeke 5.0 BTBD)
If fitted, a generator can be used to create AC power, which in turn can charge the batteries, run
air-conditioning, water heater, etc. The generator starting procedure is as follows:
ƒ Make sure the generator raw water seacock and fuel line are open and that the strainer is clean.
ƒ Check the fluid levels of the generator.
ƒ The generator battery and house battery selector switches should be ON.
ƒ All AC circuit breakers should be OFF
ƒ Using the generator control panel, port side of wheel on the console (see pic), start the generator
using the following procedure which is also shown on a plate atop the generator:
PREHEAT: Depress the PREHEAT switch first to
activate control system
START: Depress START switch while continuing to
depress PREHEAT switch. (PREHEAD also overrides low
oil pressure shutdown).
When generator starts, release START switch only,
continue holding PREHEAT switch for a few seconds until
oil pressure reaches 20 psi.
Allow the generator to run for 15 seconds, then switch the
AC selector switches to GENERATOR (GENSET).
HULL ZINC
TRIM TAB