How to test voltage regulator output?

[pict1000]

Try running a temporary wire 16 gauge or larger from the B+ terminal to the positive post of the battery and see what what voltage you get when testing the charge at the battery terminals.

Since cleaning the positive battery cable connections on both its ends didn't fix the problem, I'll be trying your B+ to battery bypass-wire test tomorrow morning. Once again, I'll be posting my results after that. BTW, my positive battery cable does have continuity -- FYI.

 

[pict1000]

Test results show that the regulator is grounded but you are not getting power from the battery to the B+ terminal of the regulator therefore it won't charge. Try running a temporary wire 16 gauge or larger from the B+ terminal to the positive post of the battery and see what what voltage you get when testing the charge at the battery terminals.

When I run a 14 gauge wire between the B+ post and the positive terminal of the + battery terminal I get a ton of sparks. So I disconnected immediately for fear of ruining something. My connecting wire is not touching anything else. What am I doing wrong?

 

[ILENGINE]

If trying to connect to the battery with the engine running could produce sparks since there is the potential for about 15 amps. If trying to connect with the engine off and getting sparks would indicate a short most likely the regulator shorted to ground, but some regulator are only half wave rectified so a shorted stator could also be an issue.

 

[pict1000]

If trying to connect to the battery with the engine running could produce sparks since there is the potential for about 15 amps. If trying to connect with the engine off and getting sparks would indicate a short most likely the regulator shorted to ground, but some regulator are only half wave rectified so a shorted stator could also be an issue.

Connecting to + battery terminal from regulator/rectifier B+ post with the engine OFF creates NO sparks at all.
So what do you suggest I might do now?

 

[pict1000]

BTW, I tried a new battery cable just for grins. Did not fix the issue. Bummer.

 

[ILENGINE]

Connecting to + battery terminal from regulator/rectifier B+ post with the engine OFF creates NO sparks at all.
So what do you suggest I might do now?

Since you are NOT getting sparks with the engine off, go ahead and make the connections between the regulator B+ and the positive of the battery, and then start the mower and check the voltage at the battery to see what you get.

Your issue is you are not getting power from the battery to the voltage regulator through the wiring harness of the mower. Could be a bad connection at the key switch, or an amp meter or some other connection that the charge system goes through. Would need the wiring schematic to follow the path.

And if the battery to regulator allows the battery to charge there is nothing that says that you cannot make it permanent. It will not discharge the battery and that is the preferred method anyway to connect the regulator to the big post on the battery side of the the starter solenoid.

 

[pict1000]

Since you are NOT getting sparks with the engine off, go ahead and make the connections between the regulator B+ and the positive of the battery, and then start the mower and check the voltage at the battery to see what you get.

Sounds good. I'll give it a shot in the morning. I can't thank you enough for your help!!!

 

[pict1000]

Since you are NOT getting sparks with the engine off, go ahead and make the connections between the regulator B+ and the positive of the battery, and then start the mower and check the voltage at the battery to see what you get...

Do I leave the existing battery cable as is while I'm doing the 14 gauge wire bypass? Or disconnect the battery cable first?

Here is my wiring diagram (I've checked 2 of the fuses -- continuity is good for both):

 

[ILENGINE]

You can leave it connected to the battery, just don't let the end that was connected to the B+ terminal contact anything metal and cause a short. Also it looks like the purple charge wire should be directly connected to the positive side of the battery. But there appears to be a 20 amp fuse in that wire. If that fuse(small chance) is blow or corroded(larger chance and possibly melted fuse holder) will cause the issues that you are having with the charging system.

This bypass wire is just replacing the purple wire in the diagram. If you get the temporary wire connected and it then charges then we know that the problem is in the purple wire. And you can go ahead and use your temporary wire as the direct replacement for the purple wire.

 

[pict1000]

You can leave it connected to the battery, just don't let the end that was connected to the B+ terminal contact anything metal and cause a short. Also it looks like the purple charge wire should be directly connected to the positive side of the battery. But there appears to be a 20 amp fuse in that wire. If that fuse(small chance) is blow or corroded(larger chance and possibly melted fuse holder) will cause the issues that you are having with the charging system.

This bypass wire is just replacing the purple wire in the diagram. If you get the temporary wire connected and it then charges then we know that the problem is in the purple wire. And you can go ahead and use your temporary wire as the direct replacement for the purple wire.

OK, super! Got it. When I get back home later today I'll try out your suggestions. Thanks!