[fishsniffer]

I have a 2002 225 SWSII that is not charging. I have two batteries with a battery switch in between. My batteries (Dual Purpose) are fairly new and charge up fine on the 110 battery charger. I checked the voltage at the lugs on the rectifier and am showing 12.6, the same as what the batteries are showing with the engine off. I've ordered the service manual but am hoping to get a jumpstart on fixing this. Where would you look first and how do you check (and where are they located) the diodes?

[WillyBWright]

I think we found the source of your problem. "Battery Switch". On most, if you switch while the motor is running, you can fry the diodes. There are more expensive switches available with protective circuitry. But once the juice has been made, it needs to go someplace. Switch off the flow and it'll find a way, usually thru the diodes. But Yamaha is good for putting fuses in strategic locations. Have a look at those.Is it a 2- or 4-stroke 225?

[rodbolt]

hello remove the plastic electronics panal cover and find a large round plug with 3 green wires. test the resistance between all three. should all be about equal. then test for resistance from eaach leg to ground. should read infinite. then check the two large fuses under the gray fuse cover. also look to see if the batt isolator wire was hooked up or not used. does the tachometer work?

[fishsniffer]

Thanks guys, I'll check out those things. I found two large relay fuses and then one inline buss fuse, they were all good. The tach does work, is this an indication that the generator(altenator) is working? As far as the switch goes, I've been completely, 100%, positive to not switch to the off position when the engine is running. I do go from 1 to all then to 2 just to switch batteries. BTW, the engine is the 2 stroke.I assume the diodes are in the rectifier?? And would have to be replaced as a whole unit?I've read somewhere that the Yamaha charge sensing doesn't like deep cycle or dual use batteries. Can this be possible, should I try a regualar battery?Thanks again,Matt

[rodbolt]

test the voltage on the red wires going to the two big metal fuses. see what voltage you have there when idling. also test them green wires. its a 3 phase altenator. you can lose one phase and it will try to work but wont.

[fishsniffer]

Thanks Rodbolt,I tested the power on those big fuses and it was equal to what the battery is reading without the engine running, around 12.5. Is it ok to disconnect the plug with the green wires to test when the engine is running or should I do that without the engine running?BTW, I replaced one of the dual use batteries with a new crankig battery. I also checked all my connections on the battery selector switch. Still no change in voltage levels.Thanks,Matt

[rodbolt]

did you do a resistance test on the three green wires in the stator harness yet ?

[fishsniffer]

No, It looked like I would have to unplug and I didn't know if I should do this while the engine is running. I don't have a sharp probe to go through the insulator, just the standard cheapy voltmeter probes. Is it ok to unplug while the engine is running? Thanks again for all your help, I really need to get this fixed since night fishing is about to kick in.Matt

[fishsniffer]

Well, I just wanted to give an update on what I found the problem to be. I ended up checking the resistance across the three green wires coming from the lighting coil. It was even across all three wires. I then checked the voltage and found a varying 15 to 45 AC volts coming off each green wire. The voltage fluctuated with the rpms. I replaced the rectifier/regulator and am now back in business.Thanks,Matt

[rodbolt]

do the stator resitance test with the engine off. test each green wire to ground, should have infinity. test each green wire to the other. should have the same resistance.

[fishsniffer]

Thanks Rodbolt. That's what I did which led me to the recitifier/regulater. I tell you, those Yamaha manuals are not a lot of help.Thanks again,Matt