[steph10m]

'02 400EX - I was having trouble with what I thought was just a bad battery that wasn't holding a charge anymore. I put a new battery on and started it up. After I shut it down then tried to start it again right away, the new bat was drained too. I jumped it with the tractor and put a voltmeter on it while it was running - it was reading only 11.6-11.8v. I would like to see around 13v or so while it's running, right. Anybody have an idea where to start with this problem? Thanks!
-Steph

 

[Redracer]

Sounds like the stator is not charging the battery.

 

[shadetree]

could be the stator..also the reg/rec isn't working..but..more than likely..it's the stator..the stator puts out ac volatge..then this current goes to the reg/rec..then this reg/rec converts it to dc voltage..the reg/rec not only charges the battery..but also send the current to the lights..and so forth..soo..ohm your stator..start with that..if it's not your stator..then it's your reg/rec. also check all your wiring just to be safe.

 

[Helmut]

I agree with Red and Shadetree. Either your stator or regulator/rectifier.

 

[steph10m]

Thanks for the suggestions guys. Now I'm a bit confused though. I put the old battery back on and started it up. I put the voltmeter on and now it was charging. I shut it down and started it back up a few times and it seemed to be charging normally. I never did test the old bat voltage while it was running, just the new one. Maybe the new battery was bad and for whatever reason wouldn't charge. At any rate it seems to be ok, I didn't mess with it that long so I guess next time I play with it I'll see what happens. . .

 

[69quadracer]

Sounds like the Reg/rec may be sticking.

 

[Helmut]

Sounds like the Reg/rec may be sticking.

Yep, that's what I was thinking. If it does it again, and it probably will, look at the regulator/rectifier.

 

[shadetree]

Thanks for the suggestions guys. Now I'm a bit confused though. I put the old battery back on and started it up. I put the voltmeter on and now it was charging. I shut it down and started it back up a few times and it seemed to be charging normally. I never did test the old bat voltage while it was running, just the new one. Maybe the new battery was bad and for whatever reason wouldn't charge. At any rate it seems to be ok, I didn't mess with it that long so I guess next time I play with it I'll see what happens. . .

don't play with it too much..you may get it excited..and it will stop working so it will want to be played with more !..lol..glad you solved it..well for now..yeah..if it does it again..you may want to replace the reg/rec.

 

[steph10m]

What does that mean - "it may be sticking?" What do I look at/test? How do I know if it's sticking and what do I do?

I've looked at the service manual and some inspections/procedures with the charging system (haven't done anything yet) but I'm just not exactly sure what to do with the results since it's not a hard failure all the time, just sometimes. Do I have to wait until it is running and won't charge and then test?

Sorry, but I've never had to do this stuff on my own so I'm kinda learning as I go.

 

[steph10m]

lol, shadetree

 

[shadetree]

What does that mean - "it may be sticking?" What do I look at/test? How do I know if it's sticking and what do I do?

I've looked at the service manual and some inspections/procedures with the charging system (haven't done anything yet) but I'm just not exactly sure what to do with the results since it's not a hard failure all the time, just sometimes. Do I have to wait until it is running and won't charge and then test?

Sorry, but I've never had to do this stuff on my own so I'm kinda learning as I go.

only way to test the reg/rec..do what i do..replace it with a new one..lol

 

[69quadracer]

Gotta like a gal that will dive in to it and get her hands dirty!!

 

[shadetree]

Gotta like a gal that will dive in to it and get her hands dirty!!

lmfao..dang..she was playing with it !!!..now thats the dirty part !.lmfao...she can work on my bike any day..lmfao.