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Discussion Starter #1
I checked all the alternator. I found this strange phenomena that I think you might consider interesting.
I check the voltage across the regulator to see if the battery is connected to the field coil(shish magnetizes the rotor so you don't need magnets) and with the key on, I get 1.5 v. with the key off. I get the battery voltage. so why if my battery is at 11.68 from testing instead of 12v+ am I getting such a low voltage(no power to the magnet) with the key on, and such a high voltage(magnets on...magnets on)with the key off.... shouldn't the key off, kill the volts into the field?
I did this test between the + battery terminal, and the regulator to field connector, while the field and regulator connector was hooked up.

It would see to me, that the key off position might allow a drain of 1 volt to run through the field coil, but the key on should deliver the 12v needed to magnetize the rotor.
 

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Discussion Starter #2
post script:

If someone put a new and updated electrical wiring system on a year younger bike at the factory, and then sold it as a year newer to get the most they could out of it, where would a person find a schematic for the machine(cause this thing has wiring similar to the 1981 XJ1100 rather than the 1980-81 XS1100) and; where can I get a wiring diagram for the regular XS1100(E,G,F) as I only have the diagrams for the Specials?
 

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I did this test between the + battery terminal, and the regulator to field connector, while the field and regulator connector was hooked up.
With the key off, the field coil should look like a virtual ground, so, measured from the + battery terminal, you should get battery voltage, as you are essentially measuring from the + terminal to the - terminal, just by way of a coil of wire. You would get the same result measuring a light bulb that way.

With the key on, engine not running, and measured from the + of the battery, the drop through the regulator to the field coil is 1.5V, which seems like a good value for a power transistor circuit. This doesn't indicate how much current is in the coil, and therefore, how strong the magnets are. If the resistance of the field coil is nominal, you can usually assume the current is correct.

All such measurements should properly be done from the - terminal of the battery, which goes directly to the case of the engine as circuit ground. Measured from the case ground, NO electrical device should have voltage on it when the key is off, save the battery side of the starter relay.
 

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Discussion Starter #4
reply

so you believe I probably have a leak somewhere when the key is off...
I thiink this way too.
lets see, if the leak is at the field, which is connected to the fuse box on one side and the regulator on the other, the most obvious leak wouls be the regulator, which sadly took an arc while I was hooking it up new. I think I fried my new regulator...
 

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Not what I said; I said you were measuring incorrectly, if you were using the + battery terminal as a reference for your meter.

Since the regulator connects directly to the battery, and may contain capacitors, a small arc may be normal. That said, you should really disconnect the battery (negative cable first) before installing a new regulator. With the battery connected, if the regulator has more than one connector, order of connection can be important.
 

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Discussion Starter #6
full monty

These older alternators are what I call a "Full Monty", that is they start with an electromagnetic fly wheel and end in an AC-DC converter and rectifier. I always thought the nessesity for simpliity was superflouous with riding(kind of high end for us bikers kind of a deal) but with the 80's came a need for complexity, and I guess after the high rolling 70's, it was time they downsized and microamped. But my deal here is that for some unknown reason, I don't have a charge, and I don't have a tach signal. There has to be a reason.

I checked all my regulator rectifier, but I don't know what I am looking for.
I took the two into the Yamaha shop where some upstart kid, said they both looked sky high to them(that was really annoying... I mean that- he said they were both good, when the readings I get, are different from each other.

I don't know what the readings mean, and I don't think he knows either.

when I check the regulator plug diode on one of them, the plug that goes to the field coil, I get readings on both polarities 1185 and 568 or so... but the other one of them(the other RR) I get readings in onlly one polarity 1185 or so. any body with experience on checking these old 80's regulators?
 

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Discussion Starter #7
will keep you informed...

opened up the wiring harness today and changed out the old broke diode, for a new one, that should help, but I ran out of test gas before I got fired up. Will try tomorrow...heh ....heh...

I spilled some gas on my non fuel proof paint job, and man like did it eat the paint off. So I would say to anyone who wants to paint their tank... use fuel proof paint.
 

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Discussion Starter #8
new diode

well the new diode didn't work with the old regulator, so I am going to swap out the new(possibly fried) regulator, before adding the cost of a new regulator to the already way over value machine...go figure just the shop time, makes this bike worth over $64000!
 

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Discussion Starter #9
new reg test

New regulator doesn't work either. so it could be fried, or I could be yahmyxs the blind f***...

so one blind guy to another, where would you look next?

lets see, continuity and no leaks to ground in the stator... field tests good too.

new diode, all wiring continuity is good, everything works except the tach and charging....

probably that regulator that I arced when I installed it... darn dang ding ...

ok.. putting a cooling fan on top of the regulator is a good idea...
they used to make these 12v computer fans with refrigerant in them... know where I can get one of these?
 

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If I had access to a schematic, I could offer better help. There are a lot of variations in charging circuits, and I can only guess from what you've posted, how yours works. I think you may need more detailed help than I can give without more data.
 

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Discussion Starter #13
now its my meter that is up a creek...
the way I see it, now that I find the relays are different from each other, is I am glad I have ordered a new relay of the proper type.
 

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Discussion Starter #14
proper type relay doesn't work either!
so here is my demise...
To test the field coil I have decided to use some of my own ingenuity.

If the field test good, and develops a good electromagnetic strength using a momentary 12v current

outside the case, and disconnected from the machine, then it should be OK.

I have decided to apply a 12v current directly to the field output wires while the engine is running

to be sure the stator is producing current under charge.

You will need a set of jumpers designed to connect the field to a good 12v battery, and a tester for

the stator current.

Description-

12v applied directly to the field, charges the rotor, and induces current through the stator.
The stator, charged by the field coil, charges the tach, the secondary relay for the reserve lighting

unit, and the battery.


Application-

When every other system on the machine is functioning properly, and no charge is developed in the

stator, there is little to assume other than the alterntor system is failing. This includes the R/R,

any relays in the circuit, any devices powered by the alternator, and any wiring and

contacts(connectors) in the circuit.

A complete test procedure for this type of system does not exist, so application of various testing

and implementation is needed, to identify the failing part of the circuit.

Testing and Implementation-

A specialized set of jumpers, from the battery to the field coil, will charge the electromagnetic

rotor rotating around the field coil, and if the stator is funtioning properly, it will produce an

induced AC current through its' 3 phase coils. Test the stator for AC on the 200vac setting on your

meter. If the stator is producing current, we will assume the stator phase coils are in functioning

order. If the stator is creating AC voltage, and the field coil has been excited with 12v, then the

regulator rectifier is not delivering the proper current to the field coil to charge the

electromagnetic rotor. If the stator is not producing current, the tach will not operate, and the

relay will not deliver signal to the reserve lighting unit.

Fully test and have the regulator rectifier retested.
 

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Discussion Starter #15
manual arrives....

I now have a complete manual that I could do some walkthroughs with anyone who wants them. But, It says the field must be @3.5ohms and the stator fields @.4ohms... mine read 0.0 and .09 bad coils.. so I am planning on rewrapping an armature I got off ebay. story is 17gage 2lbs

So I check the reg and rectifier.. rectifier looks good but.... they are one unit, so I have to replace the regulator ...again.

which me luck.. for I am great...
 

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Discussion Starter #16
fixed problem, melted diode

yeh shadetree...

you have been drinking too much orange juice while sitting under the tree...

you fried my diode didn't you???!!!

not hardly...

but I would like input on the fact that diodes that are hooked up backwards get hot and burn up, what might be connected backwards?
 
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