MJM Yachts LLC 34z Downeast, Owner'S Manual

Page: 11 / 55

CHAPTER 3 PROPULSION SYSTEM
- 11 - 34z
3.3 LUBRICATION
Both the engine and transmission use oil for
lubrication. The transmission will tend to use
less oil than the engine, but both should be
checked frequently. For the proper type of oils to
use (which may depend on the service area and
conditions) consult the maintenance schedule
below.
The engine oil may be checked on either side by
pulling the yellow dipstick on the port top of the
engine or the short dipstick shown in the middle
picture below (the shorter one provides more
accuracy). The transmission dipstick is red.
3.4 ZINCS
In addition to drive shaft, bow-thruster and transom zincs, pay close attention to the engine zincs.
See pages 35 & 36 of the Yanmar Manual. The timing for replacing of the 5 anticorrosive engine
zincs varies depending on the characteristics of the seawater, the amount of electrical current in
marinas, or could indicate (if excessive wear is noted) an electrical short on the boat, etc. Inspect
these periodically at the time of oil changes and remove the corroded area on the surface,
replacing them when they’ve deteriorated to less than 50% of original size. Otherwise corrosion
of the seawater cooling system will occur and water leakage or parts breakage will result. Be
sure to close the Kingston (raw seawater) cock before removing the plug to replace a zinc.
Freshwater Cooler (2 zincs) Engine Lube Oil Cooler (2 zincs) Intercooler (1 zinc)
(Port Forward Corner) & 2
nd
Oil Dipstick (Starboard Forward) (Starboard Side Aft)
3.5 AIR
Diesel engines use a large quantity of air for combustion. The engine of the 34z gets this air thru
grills under the cockpit coaming, both port and starboard. It is important to keep these intakes
clear and free of foreign matter. Before entering the engine, air passes thru a foam air filter which
should be checked at intervals per the maintenance schedule.
Transmission Dipstick under Bracket on ZF 280-A
2.0:1 Transmission (Looking Forward)