battery not charging By cadman (Read 1,948 times)

[cadman]

Hello all,

I have a Jonway 250T and the battery won't charge. When I hooked up the volt meter to the battery when running cold, it gets 12.6 at idle and about 13.2 at 2000 rpm. It appears to indicate it is charging. After the Scooter warms up the voltage drops down to 12.0 to 12.2 and won't go any higher. Is this the regulator getting hot and quitting or is it more likely the stator. What can I do to narrow down the problem.

[Alleyoop]

There how-to in the ELECTRICAL SECTION in the TECH section:
Alleyoop
Here is just one of them:
www.scooterdoc.proboards.com/index.cgi?board=electrical&action=display&thread=168

[cadman]

I read those. I was a little confused on testing the three yellow wires from the stator. I think I got it right. I tested from one yellow wire to another yellow wire and got 28 to 42 volts depending on which two yellow wires I tested. It sounds like the stator is good and most likely the regulator. I was just looking for confirmation.

[Cruiser]

Welcome to the forum, cadman. It does sound like the stator might be OK. The dropping voltage after the scoot warms sounds like it might happen when the fan comes on. It would seem like the regulator/rectifier (R/R) is weak, but there are other things to check out before replacing parts. All connections at the two R/R plugs should be checked for tightness along with the connector on the blocking diode. Make sure all the grounds (black battery wire and green frame wires) are making good metal to metal contact with the frame.

There are many things to do to improve the charging output. These scoots tend to have marginal charging abilities even when everything is working correctly.

[cadman]

Thanks. I have been reading a lot on here since I purchased this scooter. The frame ground wire is suspicious. I may replace it first since that would cost me nothing and check all the other connections.

[speedracer]

How old is the battery? I would take the scooter to a auto parts store and have them do a load test on the battery. Your voltage seems low to me. Mine is 13.04 without starting it and 13.75 at idle.

[tvnacman]

I would start with any connection you think might be bad or weak . I'm a fan of running heavy ground wires and being sure they make good connection .

John

[cadman]

Thanks for the replies. The battery is new. The Scooter had been sitting up for two years when I bought it. Got a good deal and so far only a carb rebuild, rear master cylinder, and starter is all it needed to run. I rode it 15 miles and when I shut it off the new battery was dead. I pulled the plastic back off and checking all the wiring. There seems to be an extra wires running to the rear tied off on the rear right side, Anyone know what they were for? Some option not on the bike, I assume.

[Cruiser]

I don't know of any extra accessory connectors in that area of the scoot. How about taking a picture so that we will have an idea what we're looking at? Maybe the diode is missing?

[dleonard]

I have the same problem on my 2008 jonway YY250T. I has stranded me 3 times due to not charging properly. The red wire from the R/R has 14 volts, but that wire changes at a nearby connector to brown that goes to the fuse block not the battery, The fused red wire at the battrey only has battery voltage. I'm a little lost now. Also my brake lights quit during all of this stuff.

[Bashan]

They build wiring harnesses that are for many different bikes so there will be unused connectors.....don't worry about them. You can have partially shorted coils on one or more of the phases (phase=yellow wire) especially on bikes that have sat. The symptom of this is voltage drop on a yellow wire as the RPMs increase and the electromagnetic field starts to jump the thin spot(s) on the wire insulation. Put a multi in series on each yellow to ground set on AC and watch the value. If it tanks with RPM that's your problem. The solution is a new stator or rewind the old one. Rich

[trvstlh]

They build wiring harnesses that are for many different bikes so there will be unused connectors.....don't worry about them. You can have partially shorted coils on one or more of the phases (phase=yellow wire) especially on bikes that have sat. The symptom of this is voltage drop on a yellow wire as the RPMs increase and the electromagnetic field starts to jump the thin spot(s) on the wire insulation. Put a multi in series on each yellow to ground set on AC and watch the value. If it tanks with RPM that's your problem. The solution is a new stator or rewind the old one. Rich ...............

Re: this post, can you please show diagram on the testing of the (yellow=phase) wires? this will tell me if stator is good correct? and if the yellow wires show a problem cuz of insulation issues the stator will need to be changed as well??

[Bashan]

This is for a 150 but it's a 3 phase so the principle is the same.