MJM Yachts 34z Express - Manual (Page 16)

CHAPTER 4 STEERING CONTROL SYSTEM
- 16 - 34z
4.7 SEASTAR HYDRAULIC STEERING
With a hydraulic system that allows both the wheel and the autopilot to move the rudder, there are some
unique requirements. For more information log onto
www.seastar.com or email the technical service
department at [email protected] or contact the nearest distributor or Rose Marine at 978-283-0293 in
Gloucester MA.
Oil Level and System Check
Even though the Seastar system is supposed to be self-
bleeding to purge any air, check the level of hydraulic fluid
weekly, by unscrewing the filler cap on the helm console
above the wheel. If you don’t see fluid, add more Seastar
hydraulic fluid.
There is a central hydraulic reservoir & helm pump mounted
just under this fill cap mounted on top of the piloting console
forward of the wheel. It supplies the entire system.
With the filler hose still screwed into the filler cap, CHECK
the steering system for proper connections of hose, tube and
fittings, possible leaks, and air removal. To do so, turn
steering wheel and pressurize very hard to port. Apply
enough force to the wheel to exceed pressure relief valve pressure. You will not harm the helm or the
system. While pressure is maintained on the steering wheel, check all port (left) fittings and line
connections. Repeat procedure by turning wheel to starboard. Watch the oil level in the helm pump when
pressurizing the steering wheel in either hard over positions. If there is no obvious drop in oil level, air has
been removed. If there is an obvious drop in oil level, you are compressing air and further filling and
purging is required. Repeat Steps 1 thru 5. If no leaks are obvious, your steering system is ready for use.
If leaks are found, correct before using. Failure to correct a leak can lower oil level in system and result in
loss of steering.
Suggested 34z Procedure
1.
Screw the plastic filler hose (found in a galley drawer) into the filler cap’s socket before
connecting it to the Seastar plastic bottle.
2. Loop the hose over 180 degrees that’s now sticking out of the filler gap, so that the bottle can
then be turned under the cap to screw it on.
3. While keeping the bottle nearly upright, squeeze about 4 inches of fluid into the tube and turn the
wheel full starboard then full port quickly, to release any air bubbles and to refill to within ¼” of
top.
4. If the steering feels jerky or strange, there maybe air trapped in the cylinder attached to the
rudder post. (Read the “Fill & Purge” instructions below) but this can usually be solved by quickly
bleeding the valves on top of the cylinder, using the discharge hose that connects the two
bleeding valves to empty oil into a container.
5. Have a helper move the wheel with a couple of short jerky motions to be sure all air is bled. Then
go back to step one to refill the reservoir. The Raymarine Autopilot has a rudder angle indicator
that is helpful in knowing whether the rudder is doing what it should.
6. If you have had to add a significant amount of fluid, be sure to (a) check for leakage and a tight fit
at all hose connections and (b) check once again for fluid level after operating the autopilot for a
short period of time to be sure that no air has been trapped in that part of the system.
Oil Level Set
Proper oil level set can be obtained by opening bleeder and turning steering wheel until fluid level
reaches top of plastic filler fitting and then turning wheel one more full turn.