joe f Posted February 18, 2010 Share Posted February 18, 2010 hi every one i have a 1981 yamaha 400 xs special , ive replaced the wiring harness , actully it twice because it fried another stator so i replaced it with another harness , replaced rectifier an the regulator , it ran last time a couple weeks every thing worked did great , then the other night started it an just shut off , i checked fuses an the main an singal were blow agin , id replace them an blow soon as pluged them in , re tried old regulator an rectfier didnt help , main fuse has ground on one side , un plug regulator short gets dimmimer but still there , un plug stator conector shorts gone , or the main red wire going to the starter ceylnoid. which i also replaced the starter celynoid , only thing ive did different to the bike is install a switch betwee the main head light wire an the ingition switch hot wire when switch is on to kill head lights and tail light. and ive had 3 or 4 different turn singal flashers 3 prong none worked so i put in a 2 prong car flasher they worked great , im in process of having stator an electro mangent checked now , but last time was the same i put on a good stator electro manget and in maybe a week it had blown it the same way . my battery is also new . and all singals an switches ect except the ingiton switch which i did check to see if was shorting an it wasnt or at least not at the time i checked it , does the head light have to be burning at all times to keep the electro manget operating in some way ? helppppppppppppp any clues here [email protected] thanks Joe Link to comment Share on other sites More sharing options...
Moderator drewpy Posted February 18, 2010 Moderator Share Posted February 18, 2010 after reading all that am I right the question is how does the charging system work? Link to comment Share on other sites More sharing options...
Speedshop Posted February 18, 2010 Share Posted February 18, 2010 If its blowing fuses with the engine off, you have a short in the wiring loom somewhere. Sounds like the wiring has been chopped about - something about a switch across the headlamp? I'd look at that. If it ONLY blows fuses once the engine is running then the charging system has lost control. This could be a faulty regulator or shorted field windings. One other thing - with the engine running or not - is the wires from the generator often wear through near the gear lever, worth carefully inspecting the wires here, a dirty messy job but I've seen plenty of 400's with this fault. The fuses are 15 amp ones are they? I had someone bring me a 400 fitted with 10 amp fuses which blew them with the engine running (headlamp 6 amps, ignition 2 amps battery charging 4 amps - pop) Link to comment Share on other sites More sharing options...
joe f Posted February 18, 2010 Author Share Posted February 18, 2010 i believe the fuses are 20 amp but it doesnt blow them all at once , it does fine for a week or so then , when it starts to blow them its no power to any thing and the short i trace to one of the plugs coming out of the stator case. un plug it short is gone , ive replaced about every thing already ,harness, regulator ,rectifyer turn singal cancel , well every thing but the ingition switch , which showed no shorts when i tested it , possibly just a used stator i got was on its way going bad huh , im gona ck once agin behind the head light before i put next stator in , on the head light kill switch i installed ect , yea the wires behind stator cover an under engine looked good and i was extra careful routing them behind the case and underneath. just real weird problem but got to find it before buying stators sends me to the poor house lol thanks pal for your reply Link to comment Share on other sites More sharing options...
Speedshop Posted February 18, 2010 Share Posted February 18, 2010 If its knocking out 20 amp fuses thats a 'hard fault' IE a wire shorted to earth somewhere. I'd deffinately look at the generator wires where they touch the engine again Link to comment Share on other sites More sharing options...
joe f Posted February 19, 2010 Author Share Posted February 19, 2010 If its knocking out 20 amp fuses thats a 'hard fault' IE a wire shorted to earth somewhere. I'd deffinately look at the generator wires where they touch the engine again Link to comment Share on other sites More sharing options...
joe f Posted February 19, 2010 Author Share Posted February 19, 2010 yea its definately a short some where , but wires look fine on the stator assembly , but i feel like the short has burned it out yet agin . only the tail light an ingition switch is all componets that havent been replaced. thanks for ya reply Link to comment Share on other sites More sharing options...
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