250B charging problem By winchesterboy (Read 1,026 times)

[winchesterboy]

I was hoping someone might give some help with a charging problem I am having on my 250B scoot.
The battery is not charging properly. While it is idling it only charges to about 12.5-12.6 VDC. If you rev it a little it goes up to maybe 12.8 volts. I recently changed out the stator because it was shorted out to the engine block. While I have it apart I also replaced the voltage regulator. Well, it charges about the same as before the changes. So I am curious about the rectifier/blocking diode now. Should the red and white wires to the rectifier have voltage to them with the ignition off?

As you can see in this photo there is 12.5 volts, battery voltage, to these wires. I thought the ignition had to be in the on position for voltage to be present, it is in the off position in this photo.


What a mess!
I do have an electric fuel pump which draws a little extra but I did install LED's in the brake lights, blinkers and the front indicators beside the headlights.
I have not completely tested the new stator. I was using "The Stator Papers IV" to check it and the second test said to put the red lead from the meter on the red output wire on the regulator and the black meter lead to the positive post of the battery. When you check the meter reading if it is greater than 0.2 volts= bad connection, I can't find a lose connection!
So anyway, if anyone knows about the voltage to the red & white wires going to the rectifier or any other helpful hints that may correct my problem, I am receptive to all ideas!

[cruiser]

The reading on these wires is normal. One side of the connector is wired directly to the battery. This is the charging path when the engine is running and the diode is conducting. It appears that there is some charging going on when the engine is running. One rule of troubleshooting charging system problems is always start with a fully charged battery. Your battery is low to start with and it would take the system quite a while to bring the voltage back up to the normal range. The battery should be at about 12.8 volts minimum before you start checking for charging problems.

[JR]

Winchesterboy Cruiser is right your charger will be revelant to the strenght of the battery. Give it a nice 3 to 5 hour slow charge and then lets test again. Also plug it all back up and test at the battery with it idling and then revved up.

Write down your readings and then do this to see about the blocking diode remove it and jump the wires that plug into it, don't be alarmed as the headlights are going to come on. Start her up and take a reading, we know the diode is doing it's job as far as not allowing the battery voltage to back feed but we don't know how well it's allowing the charging voltage to pass to the battery?

Take a reading after removing the diode and let us know what it is. The linhai with a fully charged battery will easily put out 13Vdc+ idling if all is correct.

JR

[winchesterboy]

Thanks cruiser and JR for your input/help,
Well after putting the scooter back together, enough to start it and check the voltage, the voltage reading at idle was 13.25VDC. This was still a little low so I switched back to the voltage regulator I had on the scooter previously. (since I had the scoot "naked" and the wires had gotten very hot on both the voltage regulator and the stator plugs and had even melted the plastic on one wire of the stator plug, I also changed out the voltage regulator along with the bad stator)
This made the idle voltage about 13.65-13.85VDC. (the voltage even went up to 14.15VDC with a little tweak of the throttle)
I had ordered a new voltage regulator from EBay;
cgi.ebay.com/ebaymotors/_W0QQcmdZViewItemQQ_trksidZp3984Q2em1439Q2el2649QQitemZ280588484627QQsspagenameZSTRKQ3aMEWNXQ3aIT
It was smaller than the OEM VR, but the wire colors and the plugs are the same. I don't know why the voltage, at idle, was less with this VR.....but I guess I will keep it as a backup.
While I had the scooter "naked" I removed the wires from the following connectors/plugs and "tightened" them, and put dielectric grease in them, the stator, voltage regulator, rectifier, enrichener and the cooling fan on/off sensor.
So now I guess the charging voltage is OK......but I am going to be checking it randomly!