Performance CDI on chinese atv 250cc
#21
I just installed the new stator and voltage between the two yellow wires is about 20 at idle and goes over 40 at fast clip so I guess that's acceptable. The regulator is outputting 14.6 volts constant at idle and fast clip however when I connect the red wire to the battery, the voltage falls to 12.1 at idle and barely rises to 12.8 at fast clip... Correct me if I'm wrong but I believe it should rise to about 14 volts when the engine revs up, so Im guessing there is still something not working correctly, but, what could it be????
It is normal for a discharged battery to suck up all the current available from the charging circuitry and pull down the voltage - especially at idle where the stator output capacity is reduced anyway. When the battery charges up then the battery will stop drawing charging current and the voltage will rise.
I belive I've found the reason why my ATV is not charging the battery... The CDI on my ATV is a DC-CDI which means it runs on battery power. While the rectifier may be flowing sufficient battery charging power, the CDI on the other hand keeps draining it at the same time therefore ther is never sufficient volts going into the battery in order to charge it. The question is, is there a regulator/rectifier that can produce a larger amount of voltage to supply both the DC-CDI and charge the battery at the same time???
The stator is the limiting element in the charging system. To get higher electrical wattage from the quad you need a better designed stator.
I still think your battery is suspect.
Here is a better way to measure whether your charging system is working or not:
Remove the quad fuse. Set your meter to measure DC current on the 10 amp scale. Move the red lead if necessary to the 10 amp current jack on the meter. Insert the meter leads in place of the fuse so that all the current to and from the battery passes through the meter.
Start up the quad and turn on the headlights. Your stator cannot keep up at idle running the headlights and charging the battery, so you will be reading a net battery *discharge* current coming out of the battery. Rev up the engine slowly while watching the meter current. As the engine speed increases the stator puts out more power and the *discharge*current will drop. At some point as you keep increasing engine speed the *discharge* current will diminish to zero, reverse polarity, and start to increase. The *reversal in polarity* indicates that the charging circuitry is now supplying all the power needed to run the quad and headlights, and is now able to pump current backwards through the battery charging it up. The reversal in current polarity is key. If you have that your charging system is working. Then when you turn the headlights off you will see a big jump in charging current.
Note: All meters that measure current have internal fuses. These fuses are often blown when someone hooks up the meter in current mode incorrectly. Meters with blown fuses will still measure volts and ohms just fine. So if you read zero current, and you hooked the meter up correctly, then open up the meter and check the fuse(s). Usually there is one fuse for the low current scales and another one for the 10 amp scale.
#23
Wow!! And I thought I had everything figured out... Thanks a lot Lynn, I will follow all the instructions and report back my findings cause it makes perfect sense, just that I didn't think that a bad battery could keep the voltage from increasing when the engine reved up. I have no doubt that the battery is the source of the problem because I won't hold charge for long since I've charged it with my car and after a few days it's dead even if not used. I'll replace the battery with a new one to see what numbers reflect.
Thanks again and best regards,
Thanks again and best regards,
#25
The charging problem is now solved (thank God) however after a few weeks without starting the engine, it doesn't want to start now. I checked the sparkplug and there's no spark when I crank the engine. How can I check wether the problem is the Coil, the CDI or the stator? What voltage should read at the coil terminals? what voltage should the cdi be getting from the stator wires? Sorry to keep bothering...
#26
Check the kill switch circuitry first: Unplug the CDI. Set all kill switches to the "run" position. Turn on the ignition switch.
Measure the resistance of the kill switch pin in the wiring harness to ground. It should be open (infinite resistance). If it is shorted to ground then you have a kill switch wiring problem.
If you have an open kill switch connection then verify that when you turn the ignition switch off your kill switch wire resistance to ground goes to zero.
Measure the resistance of the kill switch pin in the wiring harness to ground. It should be open (infinite resistance). If it is shorted to ground then you have a kill switch wiring problem.
If you have an open kill switch connection then verify that when you turn the ignition switch off your kill switch wire resistance to ground goes to zero.
#27
I was finally able to do the testing you recommended, all switches were working perfectly, I found out that the problem was the stator's pulser (I'm not sure if that's the correct term for the small piece that reads the timing from the flywheel) apparently I mounted it incorrectly the last time I took the cover out to change the oil and clean the engine thoroughly. I mounted it the right way and it fired right up.
Thread
Thread Starter
Forum
Replies
Last Post
ATVC Correspondent
Drivetrain, Suspension & Tires
2
09-30-2015 01:37 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)