Topic: regulator... rectifier... again! :)

[auro]

sorry guys - i know there are many threads on this but they sort of assume some knowledge of electrics, which i lack! 

i have one very simple question, really: on my cb550 f2, i seem to have this (regulator):


but can't locate at all the rectifier:


could it be that i don't have the rectifier at all, or shall i at least have this one:


i'm asking as i have charging problems, and i understand in most cases it comes from the rectifier...

is it possible i only have the regulator above?
shall i replace that one only, or both rectifier AND regulator?

many thanks in advance for the patience and help 

[luap]

Yes you need the rectifer, Im not a electric pro but im surprised it runs at all with out it
Id do a single unit regulator/rectifer combine. 7 wires 100 bucks from sirius con inc
3rd pic is a blinker relay?

[TwoTired]

The rectifier lives at the bottom of the electrical panel.  It will have three yellow, one red, and one Green wire going to it.

I don't understand why people replace these parts unless they know they a have gone bad (usually from abuse).  Each component can be tested for function.  And, they simply don't fail routinely on their own volition.  When you assemble a circuit with all known good parts, it simply must work.  No praying or chanting is required.

But, one method of repair is just to keep spending money on replacement parts until the behavior is acceptable.

The second pic is a combined regulator rectifier.  But, that one didn't come with a CB550.  And they are NOT all the same, functionally.
The third pic is a blocking diode used in the neutral light/clutch safety circuit of the starter.  All it does is keep the neutral light from coming on when the clutch is squeezed.

Cheers,

[Toxic]

Post a pic of your electrical panel that would help sort out what you have or don't have.

[auro]

guys

thanks!

i understand a little bit more now

here's a pic of my panel, as posted on another thread where i was looking for fuses etc



i can see now that the rectifier is just below the panel, with the orange-ish thingy on top of it

with regard to the regulator, it can't be easily seen here (a bit behind the panel) but it's like my first pic on the thread, only much much rustier and dusty.

and the bike won't charge the battery, so given what i could find around here i thought replacing it might do good. i'm happy to test it if you have a method

again, thx for you patience and advices!

[TwoTired]

Begin with problem verification and characterization with recorded data.
A -- Fully charge a known good battery.  Let it rest for 2 hours, off the charger, and measure the battery voltage.  (Target is 12.6-12.8V.)
B -- Start the bike and measure the battery voltage at idle, 2000, 3000, 4000, and 5000 rpm.
C -- Repeat the measurements of B with lighting off.

The above tests identify charging system success, failure, or degree of "faulty".  The success voltages are listed in the Shop manual.

D -- Assuming the above indicates faulty, do check the RECTIFIER diodes with a diode tester or ohmmeter capable of testing diodes and uses more than .7 volts to make the test(s).
Of the twelve test made in D, six must read low ohms and six must read very high ohms.

E- assuming no faults were found in D,  Measure the white and green wires disconnected from the REGULATOR.  CB750s should 6.8 ohms - ish,  CB550s/350s/ and 400s should read 4.9 ohms- ish.

F- If there are no bullet holes or road rash/divots on the alternator case, the stator is probably good.  But, you can check for yellow to yellow continuity (.35 ohms) among all the wires, and that no yellow wire has continuity to the engine case.

G- Assuming no faults found in D, E, and F, measure the disconnected terminals of the REGULATOR.  The black and white terminals should measure zero ohms (subtract meter error if there is any).  Higher than Zero ohms, indicates internal contact contamination needing cleaning and attention per shop manual.

H - Assuming D, E, F, and G have not found faults. We can verify all the of the charging system minus the regulator is functioning correctly, by using a temporary jumper to connect the disconnected white wire (normally attached to the REGULATOR) and connecting the White directly to the the battery POS terminal.  Repeat the B and C tests.  However, if at any time the battery voltage rises above 15V, stop the test.  Such an indication would prove the charging system capable of maintaining a known good battery.  If this test never achieves 15V, then there is a wire/connector issue in either the ground path leading back to the battery NEG terminal, a wiring/ connector issue withe the rectifier RED path to the battery POS terminal, or you made a mistake in D through G.

I - (not used, can be confused with L)

J -  The only parts that remain to prove or expose are the REGULATOR (in active mode) and the electrical path between the battery POS terminal and the black wire that connects to the REGULATOR.


.... To be continued in part 2 later.  ---Work in progress.---

K - Lying to and starving the regulator (Black wire voltage different than battery voltage).

L - Regulator operation/verification. (Regulator White wire output when engine revved up.)

There's a start.
Cheers,

[samIam]

I had the same issue and did all the test.   I found the issue when my ignition switch went bad.  The black wire came apart from the ignition switch.  My guess is that the wire was barely hanging on and not relaying the whole voltage, then it finally broke.  Just saying to check the black wire at the ignition switch.

[adamlwvdc36]

simply put dude between any two wires of the yellow wires on the rectifier you should read an AC voltage. Between the red and green wires you should have a DC voltage of about 13 volts.  Imagine the yellow wires are labeled A, B, and C... between the voltages between A to B, B to C, and A to C should all be the same (within .5 Volts) If theyre not, look into your generator field and stator, If they are but are low (below 10VAC [ which when rectified makes about 14 Volts]) or too high (above 12VAC [ Which rectifies to about 17 VDC]) then you still need to look at the generator assembly using the ohmmeter method Two Tired posted.  If all there is good to this point then go on to the red and green wires... Measure between them If there is ANY AC voltage present above .3 Volts (pulsating DC will have some AC characteristics but shouldnt be even close to what was on the yellow wires) then look into the Rectifier.  If all of this checks out to this point but you are still having problems, more than likely the problem is in the regulator, a device that controls the amount of excitation in the field (magnetic force) which then in turn raises or lowers the generated voltage. 

...oh yeah, do this while the bike is running, I'd hate to have you replace the generator thinking its bad because its not producing when it wont when the bikes not running.

NOW, before anyone else eats me alive, let me explain myself.  The method I have provided is so he can troubleshoot his bike without having to take anything apart unless it needs to be. and for the record, these bikes will run when the rectifier is bad... just off of AC and not DC which just means it wont charge and may fry the neutral safety circuitry, which it doesnt seem to be doing otherwise the bike wouldnt start at all.  I would be leaning towards that nasty, crusty regulator that he mentioned... which by the way can be cleaned to make it operational again....Lets deal with that after he does some testing.

Lastly, auro, If you cannot perform these tests because you dont have a meter, or dont know how to use one, then you shouldnt be messing with it (the electrical) in the first place... Sorry, had to say that.

[auro]

again, all great answers here and lots of good information

many thanks to you all

i do have a meter and will check if that's the right type for the kind of tests you describe. if not, i'll either get one or call a pro, and will avoid messing with the electrics, promised!

 

[samIam]

Here is the least confusing explanation that I've seen.  I was able to follow the directions on this one and posted my results.
http://forums.sohc4.net/index.php?topic=96307.0

[auro]

alright

finally found the time to get to the garage and give it a go

battery fully charged, then left half a day there on the bike.

bike not started, key on OFF position. reading: ~12.3
bike not started, key on ON position, lights on. reading: ~12

bike started, lights on:
~1000 rpms. reading: ~11.9
~2000 rpms. reading: ~12.0
~3000 rpms. reading: ~12.15

doesn't look right to me 

[TwoTired]

alright

finally found the time to get to the garage and give it a go

battery fully charged, then left half a day there on the bike.

bike not started, key on OFF position. reading: ~12.3
Battery is suspect

bike not started, key on ON position, lights on. reading: ~12

bike started, lights on:
~1000 rpms. reading: ~11.9
~2000 rpms. reading: ~12.0
~3000 rpms. reading: ~12.15

doesn't look right to me 

Battery is undercharged (at ~60%) or faulty, but the charging system is, at least, trying to restore it.  If you run at 3000 rpm for 10 hours or so  (Less without the headlight load), the voltage may come up to 14.5V.

You still may have a charging system issue.  But, without a good fully charged battery, it is pretty tough to evaluate it unless you insert an ammeter into the red rectifier output path.

Cheers,

[auro]

oh
wow

left the bike half a day there after a full charge...

will try again

[auro]

so, I will have time later today to do some more of the tests you suggested, and will let you know.

fyi - spoke to the previous owner, and he tells me the battery had been changed for a brand new one one month before giving it to me, which doesn't exclude the fact my battery might be faulty anyway, but makes it a bit more unlikely, no?

in the meanwhile, thinking ahead, if i find that the regulator or the rectifier are faulty, is there a unit that would replace both of them at the same time? any specific model you'd suggest?

[TwoTired]

I like the stock Vreg.  It has a 40 year reliable track record.  (And will survive EMP.)   
I don't have too much trouble making them work as they did when new.

If you have a bad rectifier diode, just about any 3 phase rectifier assy. will substitute fine.  Nice if it used the same connector as currently in use.

Cheers,

[scottly]

I like the stock Vreg.  It has a 40 year reliable track record.  (And will survive EMP.)   

Doesn't matter if the Vreg survives EMP, if the stock solid-state rectifier fails...

[auro]

[TwoTired]

I like the stock Vreg.  It has a 40 year reliable track record.  (And will survive EMP.)   

Doesn't matter if the Vreg survives EMP, if the stock solid-state rectifier fails...

I'd rather replace one part than two to get going.  And six diodes are easier/faster to find (I've got a whole bag of them in my garage) and cobble together than a Vreg.  Anyway, it was intended as a joke.  I live in Silicon valley, a prime target for a nuclear strike.  I doubt I'll be caring much about EMP repairs over radiation burns.

[auro]

so, I finally had the chance to get to the garage and try out a few things.

battery fully charged, as said, read 13.3V
again, when I start the engine up it goes down a bit, but revving up shows more current getting to the battery, up to 13.5V @ 4000 rpms, but not more, and starting at 12.1V at idle.

I removed the connection between the regulator/rectifier and the wiring loom, where you have 3 yellow wires + 1 green + 1 red.
With the voltmeter, I read the same voltage as the battery between the green and the red wires, which I believe is as expected.

When it comes to the yellow wires, I checked all combinations as mentioned above (A+B, A+C, B+C), and I get nothing, zero, nada, kaput!
There are some slight fluctuations between the 2ns and 3rd wire (B+C), but otherwise I see nothing flowing through.

Do I have to assume, then, some kind of issue with the field coil? 

{ yes, I did these last tests with the bike running, at idle  }

[Fritz]

battery fully charged, as said, read 13.3V

Looks good so far, but you should let it rest for about 2hours after charging and test again.
Did you check the "Säurestand"? If it's too low, fill it up with distilled water only.

again, when I start the engine up it goes down a bit, but revving up shows more current getting to the battery, up to 13.5V @ 4000 rpms, but not more, and starting at 12.1V at idle.

It's normal for the voltage to drop if you turn ignition on. Field and ignition coils will use some amps, so the voltage drops.
The fact that the voltage rises with revs shows that your charging system is working somehow.

I removed the connection between the regulator/rectifier and the wiring loom, where you have 3 yellow wires + 1 green + 1 red.
With the voltmeter, I read the same voltage as the battery between the green and the red wires, which I believe is as expected.

Yes, the red wire is connected to the battery, so it should read the same voltage

When it comes to the yellow wires, I checked all combinations as mentioned above (A+B, A+C, B+C), and I get nothing, zero, nada, kaput!
There are some slight fluctuations between the 2ns and 3rd wire (B+C), but otherwise I see nothing flowing through.

You must switch your multimeter to AC Voltage when measuring the output of generator. It's the only AC source, all other measurements must be taken with the DC setting.

Do I have to assume, then, some kind of issue with the field coil? 

The field coil is powered with DC battery voltage. The yellow wires are connected to the stator coils (AC).

Read the thread that Sam posted again until it makes sense to you

[auro]

Thanks Fritz - I did take the yellow wires-reading in AC mode as well, but I'll give it another try later today and will let you know.

With regard to the battery, the acid level is quite fine, I checked.

[auro]

so yesterday evening I had another go at checking the wiring.

unluckily my multimeter seems to be unable to do the resistance checks on the yellow wires - I've set the right mode and tried all different levels, but the LCD always shows "1", which means over-range... 

this said, I went back to the RPM test once the battery had a full charge (and after a couple of hours standing there).
the battery had 13.4V then, ignition key turned off.
I warmed up the engine and got it up to 4000 RPMs, as usual it slowly seems to go higher in voltage, this time up to 14.13V

So I start to wonder if the problem is not the bike, but me?
COuld it be that I drive the bike slowly most of the time, at least mostly below 3000 RPMs, and therefore it can't charge?

 

[TwoTired]

unluckily my multimeter seems to be unable to do the resistance checks on the yellow wires - I've set the right mode and tried all different levels, but the LCD always shows "1", which means over-range...

"Over range" means a very high resistance, big number.   With the probe tips touched together you should read a very low resistance, very near zero.  What does yours read?  The stator windings won't add much resistance beyond what the meter leads have as resistance, which your meter should display.
Why not tell us the brand and model of the meter, as they are not all the same.

So I start to wonder if the problem is not the bike, but me?
COuld it be that I drive the bike slowly most of the time, at least mostly below 3000 RPMs, and therefore it can't charge?

That's possible.  While the alternator is capable of 150W output at optimum speed. It only puts out about 1/3 of that at idle speed.  The stock bike with lights on draws about 120 watts whenever the key switch is on.  I forget if your bike still uses all stock components.

It could also be that your meter is lying to you, which would certainly add confusion for all.  Test equipment is not infallible.  And, some are smarter than the users. 

Cheers,

[auro]

What does yours read?

as said, "1" - which looking at the multimeter manual means... over-range?

Why not tell us the brand and model of the meter, as they are not all the same.

here it is:
http://www.amazon.co.uk/DIGIFLEX-Testing-Digital-Multimeter-Voltmeter/dp/B003NEGZLS/ref=sr_1_1?ie=UTF8&qid=1344415100&sr=8-1

I forget if your bike still uses all stock components.

yes, except for the regulator and rectifier, which have been replaced by a combo reg/rect (brand new)

thanks again for the response!

[onepieceatatime]

If your meter is reading 1 all the time, even with the tips of the leads shorted together, the meter is not working properly.
It may have a fuse to protect the meter that has blown. If you accidently connected the meter to a voltage source, while in an ohm setting, this is likely to have happened.