charging system

[rrossi]

I have a 1978 mercury 140 outboard that will not charge.Battery is good.was told somone tried to start eng with battery charger on high and that the rectifier is no good if so wear can I purchase one at a good price.

 

[jimg984]

Re: charging system

can buy here at Iboats about 35 dollars..........make sure ALL elect connections are clean and tite....never disconnect battery with engine running to see it if is charging it will kill rectifier.....when rectifier is bad most time the tach wont work, but not always.....your is probably rectifier as your are thinking..........good luck

 

[Barnacle_Bill]

Re: charging system

If you want to test it, here is the procedure.

1. Disconnect the battery leads.
2. Disconnect all wires on the rectifier.
3. Connect the red test lead to ground and the black lead alternately to terminals A and C.
The meter should show continuity.
4. Connect the black lead to gound and the red lead alternately to terminals A and C.
The meter should not show continuity.
5. Connect the black lead to terminal B and the red lead alternately to terminals A and C.
The meter should show continuity.
6. Connect the red lead to terminal B and the black lead alternately to terminals A and C.
The meter should not show continuity.
7. Replace the rectifier if you do not get correct readings.