Raymarine Autohelm ST6000, Service Manual

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Autohelm
Autohelm Autohelm
Autohelm
SeaTalk Service Manual 3
1. Rotary Drive Unit
The rotary drive unit comprises a belt drive reduction stage from the motor, and a two
stage epicyclic gearbox. An electro-magnetic clutch locks the outer ring of the first
stage gearbox when drive is required. This arrangement provides very quiet
operation with low backdrive torques.
2. Dismantling
After removing the unit from the boat and to gain access for drive motor, drive belt or
clutch replacement, the following steps apply:-
a) Unscrew and remove two caphead screws using M3 alien key. These screws
secure the plastic cover to the main unit. Ease the power supply and clutch cables
through the grommet whilst removing the plastic cover and finally remove the cover
altogether.
b) If servicing the clutch assembly remove the dust cover as above then unscrew and
remove the two caphead screws which secure the clutch rotor and plate assembly to
the two pillars holding it off the main assembly (use a M3 alien key).
c) The clutch rotor is fixed to its plate by one caphead screw through the centre which
is spring loaded. Therefore, care should be taken to hold the clutch rotor as the screw
is removed.
d) If servicing the drive motor assembly, remove the dust cover as above then
unscrew and remove the 4 x 6mm caphead screws with washers and also the two
long hexagonal studs at the centre sides of the main assembly. The mounting cover
assembly can now be removed from the master plate. Care must be taken when
removing the cover assembly to ensure the drive gear disengages without damage.
This is best done with the mounting cover placed down on the bench and the drive
motor facing uppermost so that the planet gears within the mounting cover will stay in
place. If they become dislodged keep them safely ready for reassembly.
e) Support the motor, unscrew and remove the three M6 caphead screws and
washers securing the motor to the master plate and slip the drive belt off the pulley.
f) If replacing the drive belt it will only be necessary to loosen the three screws that
secure the motor to take the tension off the belt whilst it is slipped off both pulleys.
3. Reassembly
In all cases rebuilding the unit is a straight reversal of the above procedures, but the
following points should be noted:-a) When refitting a drive motor ensure that the drive
pulley is fitted to the motor shaft in the correct orientation (general assembly). Note
also that the motor shaft should be degreased with a suitable solvent and dried off
thoroughly before bonding the pulley in place using Loctite 601 or equivalent
anaerobic adhesive. Following bonding the unit should not be placed under full power
for at least one hour.