Electrical issue

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WEM said:
Thanks again for the excellent advice/ideas. I have a new piece of info after today's fiddling around. I installed a new plastic fuse holder with a 20 amp SFE fuse and the bike again started up and ran perfectly for about 15 minutes or so before I turned it off. Idle was steady around 1000rpm. I didn't go for a test ride as I wasn't looking forward to probably having to push the bike home so the bike didn't get up to full operating temp. I took the opportunity while bike was running to test alternator output. With bike off, multimeter read 12.20 v on battery. Turned ignition on and reading dropped to 11.93 v. Started bike and reading at idle was 11.93 v. The interesting thing occurred when engine was revved to 4000 rpm. At 4000 rpm, reading on battery was 11.99 v. It seems like alternator is producing hardly any current. I mentioned earlier that, prior to this whole episode of the bike melting fuse holders, that the red WLA indicator light would come on when the ignition was switched to on position but would go off as soon as bike started, no matter if idle rpm's were below 1000 rpm. After the fuse holder incident, the WLA light stays on after start until rpm's reach over 1000 rpm. I know this is supposed to be how the WLA works but the interesting thing is this is a new development on this bike which only started after first fuse holder melted. I'm not sure if the dodgy alternator might be the cause of the melting fuse holder problem, a result of the fuse holder problem or unrelated at all.
Click to expand...

Here are a few things to check on your Alternator:

1) Disconnect the alternator stator wires from the rectifier. Check continuity with a multimeter. There should be very low resistance in this circuit (1-2 ohms)
2) Check continuity between the stator wires and ground. There should be no continuity.
3) Set the multimeter to read at least 100 VAC, start the bike and check the AC voltage between the stator wires. You should see 22-24 VAC before the engine revs hit 2000, and upwards of 40+ VAC at 4000 RPM and above.
4) Connect an incandescent headlight bulb across the stator wires and start the bike. The light should glow brightly at 1000-1500 RPM. Revving over 2500 RPM should blow the bulb filament.

Try these and report back.
 
Derek,

As per your suggestions, I made the following observations. (For reference, my multimeter beeps indicating continuity if the measured resistance is less than 20 ohms.)
1) I checked the continuity across the two stator wires at the rectifier. The meter beeped, indicating continuity. The reading settled at 1 ohm.
2) White/green stator wire: meter beeped, indicating continuity between the wire and ground. The reading settled at 1 ohm.
Green/yellow stator wire: meter beeped again, indicating continuity between the wire and ground. The reading settled at 1 ohm.
3) AC Voltage between the stator wires: at idle = 5.4 VAC, at 4000 rpm = 18.6 VAC.

The results for Tests 2 and 3 were not what you indicated should be expected. Do these results, together with the previously noted low voltage reading of 11.99 volts at the battery at 4000 rpm, indicate a defective alternator?
 
I would say that your stator is definitely grounded out somewhere. Before you go pulling the cover off of the primary, disconnect the stator at the connections that live between the engine and transmission and double check reading 2). This will completely eliminate any possible wiring harness faults contributing to this grounding problem.

But yes, if those readings are the same, the stator will need to come out and be looked at.
 
Derek Wilson said:
I would say that your stator is definitely grounded out somewhere. Before you go pulling the cover off of the primary, disconnect the stator at the connections that live between the engine and transmission and double check reading 2). This will completely eliminate any possible wiring harness faults contributing to this grounding problem.

But yes, if those readings are the same, the stator will need to come out and be looked at.
Click to expand...
Great opportunity to upgrade the alternator .
 
WEM said:
Derek,

As per your suggestions, I made the following observations. (For reference, my multimeter beeps indicating continuity if the measured resistance is less than 20 ohms.)
1) I checked the continuity across the two stator wires at the rectifier. The meter beeped, indicating continuity. The reading settled at 1 ohm.
2) White/green stator wire: meter beeped, indicating continuity between the wire and ground. The reading settled at 1 ohm.
Green/yellow stator wire: meter beeped again, indicating continuity between the wire and ground. The reading settled at 1 ohm.
3) AC Voltage between the stator wires: at idle = 5.4 VAC, at 4000 rpm = 18.6 VAC.

The results for Tests 2 and 3 were not what you indicated should be expected. Do these results, together with the previously noted low voltage reading of 11.99 volts at the battery at 4000 rpm, indicate a defective alternator?
Click to expand...
I'm sure you do have an issue, but just in case you are not aware some meters show "1" in the display when they are out of range. (meaning you may have the range set too low).
 
Reading through this thread, it seems that your stator has failed.
I don't know exactly how grounded stator coils affect the system but been told that replacing is needed. Anybody knows?
If you just replace it, you still don't know why the fuse holders melts.
The fuse holder melts because too much current is going either into the battery or out from it.
The easiest way to find out, is to use a DC clamp ammeter. It will tell you both how much current flows and the direction of it.
Also check with the clamp ammeter set in AC mode, that no AC is flowing into the battery.
Even the 60W dynamo in the magdyno on my WD16H could supply enough current to make the battery ball shaped, when the regulator failed.
So both the charging system and all current consuming parts could be culprits.
A test could be to disconnect the charging system, top up the battery and do a test ride.
 
Last edited:
Derek Wilson said:
I would say that your stator is definitely grounded out somewhere. Before you go pulling the cover off of the primary, disconnect the stator at the connections that live between the engine and transmission and double check reading 2). This will completely eliminate any possible wiring harness faults contributing to this grounding problem.

But yes, if those readings are the same, the stator will need to come out and be looked at.
Click to expand...

As suggested, I disconnected the stator wires coming out of the back of the inner primary from the rest of the wiring harness at the connection to the wiring harness located between the engine and transmission, and repeated Tests 1 and 2. I set my multimeter to 200 ohms on the ohmmeter scale, which is the lowest reading on that scale and recorded the following:

1. across the W/G and G/Y stator leads, the reading was 0.5 ohms.
2A. between the W/G lead and the engine block, the reading was 0.7 ohms.
2B. between the G/Y lead and the engine block, the reading was 0.7 ohms.

The readings for test 2 indicate that there is very little resistance which indicates continuity between the two individual leads and ground: ie. indicating that the stator is grounded.

However, I repeated test 2 using a test light probe. I checked the test light first by attaching the alligator clip to the positive battery terminal and touching the probe to the engine. The light lit up. I then touched the test light's probe individually to the W/G and G/Y leads. The test light did not light up for either wire: indicating that the stator is not grounded?

I am at a loss to explain why the two tests would give different results. Am I doing something wrong here or am I mis-interpreting the results?
 
I forgot to mention that I also repeated the test for AC voltage from the stator at the connection point between the engine and transmission. At idle, approximately 1000rpm, reading was 4.5 VAC. At 4000rpm, reading was 18 VAC. The VAC readings are still well below what would be expected.
 
WEM said:
I forgot to mention that I also repeated the test for AC voltage from the stator at the connection point between the engine and transmission. At idle, approximately 1000rpm, reading was 4.5 VAC. At 4000rpm, reading was 18 VAC. The VAC readings are still well below what would be expected.
Click to expand...

There is definitely something up with your stator - I would be looking for another one.
 
WEM said:
The readings for test 2 indicate that there is very little resistance which indicates continuity between the two individual leads and ground: ie. indicating that the stator is grounded.
Click to expand...

An internal short to the stator laminations is possible, but very rare. I suspect that your alternator wires are shorted to ground somewhere, either inside the primary or where they exit out the back. It's time to pull the primary cover off and have a look-see.
 
Thanks to everyone for their help. It looks like the stator or stator wiring is an issue. I have had a close look at all the visible wiring starting at the point where the stator leads leave the back of the inner primary case right to the reg/rec and no obvious issues are apparent. I'll have another look just in case I missed something. Most of this section of the wiring harness is heavily wrapped.
I'm still not sure why a bad stator would result in a melted fuse holder which is where this whole situation started. I checked the rectifier component of the Podtronics reg/rec as per Grant Tiller's procedure and it tested fine, but I'm wondering if it's possible that the regulator component is faulty and is letting excess current/voltage past the reg/rec to the fuse holder?
 
WEM said:
I'm still not sure why a bad stator would result in a melted fuse holder which is where this whole situation started. I checked the rectifier component of the Podtronics reg/rec as per Grant Tiller's procedure and it tested fine, but I'm wondering if it's possible that the regulator component is faulty and is letting excess current/voltage past the reg/rec to the fuse holder?
Click to expand...

This is a really good point, and it's hard for me to envision how the 2 conditions could be related. Your melted fuse holder says that a lot of current is flowing from the battery to ground, and the only path for that back to the alternator wires would be through the Podtronics. That can only happen if the diodes in the rectifier are shorted.

Take your ohmmeter and check between the +/- outputs and the AC inputs on the Pod. Also check between + and -.
 
WEM said:
Thanks to everyone for their help. It looks like the stator or stator wiring is an issue. I have had a close look at all the visible wiring starting at the point where the stator leads leave the back of the inner primary case right to the reg/rec and no obvious issues are apparent. I'll have another look just in case I missed something. Most of this section of the wiring harness is heavily wrapped.
I'm still not sure why a bad stator would result in a melted fuse holder which is where this whole situation started. I checked the rectifier component of the Podtronics reg/rec as per Grant Tiller's procedure and it tested fine, but I'm wondering if it's possible that the regulator component is faulty and is letting excess current/voltage past the reg/rec to the fuse holder?
Click to expand...

I know that a fully grounded out AC side will pop the fuse the moment that the alternator tries to charge, when using a Podtronics. It could be that a low stator resistance will act like a load that will heat the fuse without popping it. It also could be that there was not a good connection to the fuse within the holder that was acting like a heating element.

I am guessing that it was a combo of conditions that lead to the fuse holder over heating.

FWIW - I have actually started running a lower amperage fuse - my bike only needs about 80 watts to operate everything (including signals, horn has it's own fuse). I run a 15 amp, but could likely drop down to a 10 amp.
 
BUT...overcurrent is what a fuse is there for so again, WHY did the fuse holder melt instead of the fuse blowing? IMO, the "overcurrent" either didn't pass through the fuse (bad connection on the battery side of the fuse holder) OR there was very high current that was below the fuse rating but sustained for a long period of time. At least, that's my guess. In any case, it will be interesting to discover what the problem is/was.
 
Is it possible that there is tension on the fuse wires that is causing separation between the fuse and the contacts? This might lead to arcing and overheating. Possibly try a spade fuse instead.
 
Thanks for all the assistance. I will be replacing the alternator as a winter project this year. I'm also thinking of replacing the reg/rec at the same time. My early research indicates that a 3 phase Lucas alternator and a Shindengen SH775 might be good options. I like the Shindengen because, when the battery is charged it opens the AC line taking all load off the alternator, compared to the Podtronics which just shorts it out.
 
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