|
Home > Archive > Electrical Engineering > June 2007 > Mercury outboard
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
|
|
| bobelon 2007-06-25, 5:25 pm |
| We have a 25hp Mercury outboard that is not charging the battery.
Can anyone supply a diagnostic for this application? We do not have
any manual.
| |
| gfretwell@aol.com 2007-06-25, 5:25 pm |
| On Mon, 25 Jun 2007 17:08:05 -0000, bobelon <ebobbyray@gmail.com>
wrote:
> We have a 25hp Mercury outboard that is not charging the battery.
>Can anyone supply a diagnostic for this application? We do not have
>any manual.
I assume you don't see a rise in voltage across ther battery with the
engine running.
You have a very primative chatrging system. There is a coil under the
flywheel and a bridge rectifier mounted in a potted block somewhere on
the motor (location varies by model) trace the red wire back from the
starter to a block with 2 yellow wires that dissapear under the
flywheel. That is the rectifier. There are only 2 parts. If you have
16-20 VAC on the yellow wires you are lucky and you just need a
recrtifier. No volts on the yellows and you probably need a stator.
I can probably come up with the correct ohm readings across the stator
but my guess is a bad one will read open or shorted to ground. I think
it should be 400 ohms or so but that is a rusty memory. I do have a
book at home.
BTW I have just used a big block bridge rectifier for the $40 mercury
part but that is not the recomended fix On these little 9a charging
systems they do not have a regulator. That kicks in with the 16a
system.
| |
| bobelon 2007-06-25, 5:25 pm |
| On Jun 25, 2:18 pm, gfretw...@aol.com wrote:
> On Mon, 25 Jun 2007 17:08:05 -0000, bobelon <ebobby...@gmail.com>
> wrote:
>
>
> I assume you don't see a rise in voltage across ther battery with the
> engine running.
> You have a very primative chatrging system. There is a coil under the
> flywheel and a bridge rectifier mounted in a potted block somewhere on
> the motor (location varies by model) trace the red wire back from the
> starter to a block with 2 yellow wires that dissapear under the
> flywheel. That is the rectifier. There are only 2 parts. If you have
> 16-20 VAC on the yellow wires you are lucky and you just need a
> recrtifier. No volts on the yellows and you probably need a stator.
> I can probably come up with the correct ohm readings across the stator
> but my guess is a bad one will read open or shorted to ground. I think
> it should be 400 ohms or so but that is a rusty memory. I do have a
> book at home.
>
> BTW I have just used a big block bridge rectifier for the $40 mercury
> part but that is not the recomended fix On these little 9a charging
> systems they do not have a regulator. That kicks in with the 16a
> system.
Thanks, Just what I was looking for, some color codes.
| |
| gfretwell@aol.com 2007-06-25, 5:25 pm |
| On Mon, 25 Jun 2007 20:31:18 -0000, bobelon <ebobbyray@gmail.com>
wrote:
>On Jun 25, 2:18 pm, gfretw...@aol.com wrote:
>
>Thanks, Just what I was looking for, some color codes.
I seem to remember now that an ohm reading on the charging coil is
low, an ohm or so, the "couple hundred" is the ignition side.
|
|
|
|
|