Without getting into any of the background and exchanges of information with
a fellow Yammie 9.9 HiThrust owner in Australia (our voltages were way too
high, should be regulated to around 14.4v), here's the procedure I used for
replacing my voltage regulator with the motor installed in the boat.
The procedure is simple but requires patience and a cushion for one's knees.
Be sure to have a long thin grabbing tool to retrieve dropped screws. All
screws require a 10mm socket wrench (I used 1/4" drive with various
extensions). Need a flat-blade screwdriver to gently pry open two cable
clamps. I recorded this so I can refer to it next time and am sticking a
copy into my Yamaha manual:
1. Lower the motor into the water and remove top cover
2. Undo the choke linkage by popping down the retaining plastic piece and
simply pulling the arm away from the lever on the black housing (forward end
of motor)
3. Unscrew the two top screws on the black housing
4. Unscrew the one horizontal bolt on the black housing, careful to hang
onto the nut
5. Pull out this black housing and disconnect the two wires for the oil
pressure light. This allows complete removal of this housing.
6. On the forward end of motor is the regulator mounting bracket which also
has a rubber housing going over the starting solenoid. On this bracket,
unsnap the two wire retaining clips and loosen the wires
7. Undo the four screws holding the regulator bracket to the engine. Note
how the wire bundle from the top is routed under the bracket. Note that the
top starboard screw is a little longer and retains THREE black ground wires.
The lower portside screw fell down into the engine both when I was removing
it and twice when I was replacing it. Easier to do the final unscrewing (and
when later screwing it back in) with one's fingers. Retrieval of the screw
involved first tilting the engine to get the screw to move into view and
then retrieving it with the long snaky grabber.
8. With the bracket holding the regulator now loose, hold and pull the
rubber boot off the starter solenoid (the rubber boot stays attached to the
regulator mounting bracket).
9. Disconnect each of the wires leading to the regulator (snap out
connections) . Note the wire color coding, which is consistent with each
connection. Careful not to drop the regulator/bracket when the last wire is
disconnected.
10. Take out the bracket and on the workbench unscrew the two screws holding
the regulator (they were very highly torqued on mine).
1l. Replacement is reverse of above. Be careful to be neat with the wiring
and not pinch or stress any of the wires when reinstalling.
FWIW,
Joe Siudzinski
