- Joined
- Jul 18, 2011
- Messages
- 18,039
I replaced the alternator on the starboard engine today . . . 6 hrs
It looks like the engine was built around the alternator as it is quite buried under the heat exchanger and mounts onto the cross-over assembly. Total nightmare.
.
.
I thought I would document a bit of the process for those who may be needing to do the same on one of these in-house (Mercury) built engines (6.2 or 4.5). I think the RWC versions (Red Labels) are more straight forward, the SeaCore (Blue Labels) are a challenge.
The problem is that you need to get to the back of the alternator to remove the fasteners and the wiring, as there is hardly any slack to the wiring.
.
.
The key steps were:
1) I had to drain down about 1/2 of the coolant . . .
2) Then remove the cowling and unfasten the PCM and its base so you can pull it along with the wiring harness out of the way. I had to cut a few zip-ties along the way.
3) The port side bolt holding the alternator in place comes from the back and threads to the front, so there is a hose that has to come off to allow access.
4) The hose that comes from the top of the starboard exhaust manifold to the heat exchanger need to be un-done. and the straps holding the heat exchanger need to come off.
5) Then it was a matter of lifting and propping up the heat exchanger high enough to get good access to the alternator. I'm sure the service manual prescribed method is to remove the heat exchanger entirely . . . I was not about to do that, so I just lifted it up about 3" on the starboard side to access the wiring.
.
.
6) Even so, it took a little finesse to get the old alternator out.
.
.
Alternator removed . . .
.
Here is the new one ready to go in. . . . just checking vs. the original one to make sure they match.
.
.
7) Things go back together pretty much in the reverse order.
.
.
Overall, not a great design by any means and a half inch of room here or there would have made a world of difference. But . . . pretty typical for I/O engines.
By the time I got things put back together, it was beer o'clock,
So I'll do a few finishing touches tomorrow and test the new alternator out. 
It looks like the engine was built around the alternator as it is quite buried under the heat exchanger and mounts onto the cross-over assembly. Total nightmare.
.
.
I thought I would document a bit of the process for those who may be needing to do the same on one of these in-house (Mercury) built engines (6.2 or 4.5). I think the RWC versions (Red Labels) are more straight forward, the SeaCore (Blue Labels) are a challenge.
The problem is that you need to get to the back of the alternator to remove the fasteners and the wiring, as there is hardly any slack to the wiring.
.
.
The key steps were:
1) I had to drain down about 1/2 of the coolant . . .
2) Then remove the cowling and unfasten the PCM and its base so you can pull it along with the wiring harness out of the way. I had to cut a few zip-ties along the way.
3) The port side bolt holding the alternator in place comes from the back and threads to the front, so there is a hose that has to come off to allow access.
4) The hose that comes from the top of the starboard exhaust manifold to the heat exchanger need to be un-done. and the straps holding the heat exchanger need to come off.
5) Then it was a matter of lifting and propping up the heat exchanger high enough to get good access to the alternator. I'm sure the service manual prescribed method is to remove the heat exchanger entirely . . . I was not about to do that, so I just lifted it up about 3" on the starboard side to access the wiring.
.
.
6) Even so, it took a little finesse to get the old alternator out.
.
.
Alternator removed . . .
.
Here is the new one ready to go in. . . . just checking vs. the original one to make sure they match.
.
.
7) Things go back together pretty much in the reverse order.
.
.
Overall, not a great design by any means and a half inch of room here or there would have made a world of difference. But . . . pretty typical for I/O engines.
By the time I got things put back together, it was beer o'clock,
So I'll do a few finishing touches tomorrow and test the new alternator out.
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