A/C or D/C Stator By cp (Read 2,305 times)

[cp]

I bought a 2010 Jonway YY250T water cooled scooter with the 172mm engine.  It wasn't charging the battery so I changed the regulator/rectifier. It still wasn't charging the battery so I changed the stator (18 pole D/C).  It ran for a while and everything died.  Now I'm wondering if my scooter uses a D/C or A/C stator.  Can you help me?

[tvnacman]

I have not seen any 250cc engines that use ac powered ignition (not to say they don't exist) . Did the stock stator have an ac coil for ignition ? Does the replacement have an ac coil for for ignition power .

Stators only produce ac power !

John

[cp]

Not sure what you're asking about "ac coil for ignition". I know the battery only turns the engine over. The CDI is powered by the stator and appears to be A/C.

[Alleyoop]

Here is a 250 CDI:
SEE THE BLACK WIRE on the two plug, test that wire with the KEY ON either with a 12v light tester or a volt meter. If the test light lights up when you probe the BLACK wire it is DC if nothing it is AC with the multi meter if it registers 12v it is DC if nothing it is AC BUT YOU HAVE TO HAVE THE KEY ON.

[Bashan]

Everything the guys said is true. Did you put a multimeter on the battery terminals when the bike was running to see what the charge circuit is doing?

[cp]

OK, tested as directed. It's a D/C CDI. On the body of the CDI it's marked SMDB250C 1007 MD080603. It's manufactured by SANXIN.

[cp]

At idle 12.3. At 4-5000 12.68.

[dmartin95]

Feb 7, 2015 10:11:21 GMT -6 cp said:

I bought a 2010 Jonway YY250T water cooled scooter with the 172mm engine.  It wasn't charging the battery so I changed the regulator/rectifier. It still wasn't charging the battery so I changed the stator (18 pole D/C).  It ran for a while and everything died.  Now I'm wondering if my scooter uses a D/C or A/C stator.  Can you help me?

If you already changed the R/R and you also changed the Stator once before, perhaps you just have a bad battery that will not hold a charge any more.... It's also possible that one of your wires has a dirty terminal or short somewhere in the circuit that is preventing your battery from getting a charge.

If you have a multi (or even volt) meter, unplug your stator and check each yellow wire....If I recall, it should be around 40VAC... You can also leave it plugged in and check at your R/R where the yellow wires meet up.... However, your voltages will be different when the R/R is plugged in... Again if I recall correctly you should be around 5-7VAC when the R/R is plugged in...

My voltage numbers may be inaccurate and you may want to double check from a different source..But test your stator before you go buying a new one. 

[Bashan]

Feb 8, 2015 16:31:40 GMT -6 cp said:

At idle 12.3. At 4-5000 12.68.

Those charging voltages are anemic. You need 13+v DC to keep up with charging and lights etc. The bike probably shut off because the CDI was no longer getting adequate voltage. DM is correct, check your wires. Check your stator for AC voltage on each two yellows unplugged like this:

It should be 40 at idle and 70 at speed (approx.). The battery is a consideration, it may have a bad cell, that would be reflected in your charging voltage. Is the stator you swapped OEM or equivalent? I'm wondering if you roasted the R/R. The CDI is not involved in the charging process. That's all stator and R/R.

[tvnacman]

Feb 8, 2015 16:31:40 GMT -6 cp said:

At idle 12.3. At 4-5000 12.68.

Is you cooling fan on ? Does it cycle whats going on ?
Were the voltage readings taken at the battery ?
I would recheck the dc voltage on the red wire at the regulator to ground . Then check at the battery again and compare .

John

[cp]

When I was changing out the stator/pickup, the right side cover hung up on something.  I thought it may have just been the two rubber grommets for the stator/pickup. So I just carefully/slowly/evenly tightened done the bolts. I went to start the engine and it wouldn't turn over. The battery was fully charged. I tried a second time and heard a metalic bang then the engine turned over but did not start. After a few more tries the engine started. After a few days, I could not start the engine.  I checked the three yellow wires coming from the stator and I was only getting 10.1 VAC.  And that's where I am today.

I checked the three wires coming from the stator for grounding.  No grounds found.  Good right.

With the grommets being so tight on the right side cover, I was wondering if I may have cut one of the wires to the stator or pickup.  I removed the cover and checked OHMs.  I noticed that when I pressed the grommets the OHMs would increase.  I can't remember by how much.  I'm going ahead and change the stator/pickup, but this time, trim the grommets so that I don't have so much pressure/tension on the wires through the grommet.  I'm also going to change out the rotor flywheel and get a r/r from Tony at Oregon Motorcycle parts.  In fact he just emailed me to let me know he has all the info he needs.

[tvnacman]

Would be a shame if it was a bad blocking diode or cooling fan switch . Did you give tony info that you did not post here ?

John

[cp]

I had already replaced the blocking diode.  They call it a mini relay on the parts website. I'm changing out the fan switch since I have all the body parts off right now. The fan didn't seem like it was coming on. So I applied 12v directly to the fan just to make sure it was working. It was.

What other information would Tony need/want? I thought his r/r just put out more amps/volts than what's available from the parts guys.

I want to put on a volt meter so I can watch the charging while I right.  What's a good meter and how do you install it?

[JR]

Any volt meter will work even a cheap digital one off of ebay. I installed one myself. Tie the positive side of the meter to the black wire off of the ignition and the other side to ground and it'll work fine.

JR

[tvnacman]

here is the style I used .

John