Rectifier Cooked

[MiamiU]

Well,

We were at the lake today, got to our favorite fishing hole. Shut the engine down and smoke was coming from under the cowling. The red lead on the rectifier burned all the way through. Took the boat back to the ramp and pulled her out.

I have a few questions on this one...

1. What would have casued it to burn?
2. What happens when one goes bad?
3. Since I caught it pretty quick, what damage might it have casued?

Thanks!

 

[angus63]

Re: Rectifier Cooked

What motor/year?
Usually overload,insulation breakdown, bad battery, corrosion on connections, age.......... cause meltdown. Check stator resistance, all connections, and replace.

 

[ezeke]

Re: Rectifier Cooked

Any source of voltage that tries to enter the rectifier in the wrong direction will burn the diodes that make it work. If the heat melts the potting in the rectifier, the wiring can fuse with other wires and cause smoke or even fire. Then it is possible for the 12 volts from the battery to flow through the rectifier and destroy components of the ignition system.

Common causes of rectifier problems are:

1. Battery cables reversed;

2. Battery cables loose;

3: Battery cables disconnected while engine is running;

4: Bad ignition switch;

5: Bad battery switch;

6: Voltage applied while testing engine components;

7: Bad or weak battery or battery cables.

8. Etc.


Be sure to disconnect the damaged rectifier completely before starting the motor again.

 

[Dhadley]

Re: Rectifier Cooked

It really depends on which rectifier you have. All of the suggestions are valid. If it's a water cooled reg / rec you may have air trapped at the top of the block in the center water cavity. The water cooled ones won't cool unless there is water there.