3 yellow wires ( Thanks for your help) It's fixed By paulpaul (Read 920 times)

[paulpaul]

I have a 250b Yamaha clone. There are three yellow that come out of the rectifier go to a plug that has wires that go to the front of the scooter. Those 3 wires are very hot. They will sooner or later burn up. There are 4 wires that come from the stater. 3 are yellow one is blue. They are not hot. I have checked the plugs to make sure their tight. So a loose connection is not the problem. I believe i have a short some where up front where the yellow wires are going. all the diagrams i have found do not show where the yellow wires from the rectifier are going. The two sets of 3 yellow wires from the back ,the ones going to the rectifier and the ones that go to the stater have the same style plug. In other words you can plug either in to the other. When you change them you get the same results. The same 3 yellow wires get hot. I have been having a problem of no power . The scooter was running 70 to 75 then dropped back to 45mph and would run no faster. I believe this problem i found with the rectifiers getting hot is causing this problem. I thank the 12 volts is being robbed by the short. Anyone had this problem or have a good wiring diagram that shows all 6 yellow wires and where the should go? Thanks Paul

[tvnacman]

Paul
can you shut off all the lights when the scooter is running , if so I would see if this cools down the wires . the voltage in the yellow wires should be AC , if your lights are AC and you shut them off the wires should cool down .

John

[paulpaul]

Thanks for getting back to me. I have 6 yellow wires. 3 come from the stater they should be ac. The 3 that come out of the rectifier i thought should be dc? Now to answer your question. I'm going to pull the front plastics tomorrow and track down the 6 yellows with an ohms meter. Find out where they go and look for a short or something pulling to many amps. I put a new regulator on it today . If you check at the battery you are charging correct. Their is no ac ripple at the battery. It's dark here now . I'm going to get back on it tomorrow. Whats really bugging me is i cant find a diagram that show's all 6 yellows. I will get back tomorrow. Looks like this one is going to be fun. I have read several articles where this plug with the 3 yellow wires is burned completely up. But not any of them let me know at the end What the repair was. Thanks Paul

[cruiser]

The 3 yellow wires from the stator are the AC output wires which connect to the 3 yellow input wires of the regulator/rectifier. The regulated DC output is the red wire on the other connector. The black wire is a voltage sensing wire which is an input to the R/R and is used by the R/R to regulate the output voltage. The green wire is a ground.

The stator is always running at maximum output and the R/R determines how this power is used. Turning off the lights will only cause the R/R to shunt the excess stator output to ground. The actual amount of current going through the yellow wires will remain the same with lights on or off. Poor connections at the plug for the yellow wires can cause an overheat problem and a defective R/R can cause the same thing.

[paulpaul]

Thanks Cruiser!! I can not believe that was it,but it was. I had tightened them up before and there was no difference . I hated to cut the wires and put new connectors on them. I did and now those wires that were getting hot are not .There is a little warmth near the rectifier on the yellow wires but not much. I added a small CPU 12 volt fan on the rectifier. It is running cool now. Sorry for not listening ! I should have known better. Thank you again. Pw

[cruiser]

Your welcome, Paul. The connector where the 3 stator wires feed to the R/R is a common trouble spot. Some people even solder the wires instead of using the connector.