Das MZ Forum für MZ Fahrer

Hallo Leute,

Entschuldigung, ich benutze den Übersetzer aus dem Englischen...

Mein Ladelicht leuchtet manchmal sehr schwach, wenn ich mit meinem 251er fahre. Es ist extrem dunkel, um es bei Tageslicht überhaupt zu sehen, aber ich habe eine Spannungsanzeige, die ich seit 2016 am Lenker festgeschnallt habe, damit ich sehen kann, wann Insbesondere der Akku wird manchmal nicht aufgeladen.


Bisher habe ich die Bürsten und den Bürstenhalter ausgetauscht. Aber ich habe auch tatsächlich einen anderen Rotor ausprobiert. Die Artikel selbst sehen alle in ordentlichem Zustand aus und weisen noch gute Gebrauchsspuren auf.

Mein nächster Punkt, den ich mir ansehen sollte, obwohl ich das Gefühl habe, es bereits kurz getestet zu haben, ist, den Spannungsregler zu ändern. Derzeit habe ich einen Festkörper, der beim Kauf auf dem Fahrrad war (hat jetzt fast 20,000 Meilen in meinem Besitz zurückgelegt, ich habe keine Ahnung, wie lange der Artikel davor auf dem Fahrrad war) - obwohl ich viel davon habe mechanische zum Ausprobieren.


Ein Teil von mir denkt jedoch, dass es nicht der Spannungsregler ist, da der Ladevorgang manchmal intermittierend ist, sowohl beim Starten als auch beim Stoppen während der Fahrt. Und manchmal ist es ein kleines Glücksspiel, ob die rote Ladekontrollleuchte leuchtet, wenn ich die Zündung einschalte, manchmal nicht. Ich glaube also nicht, dass der Spannungsregler selbst in diesem Fall erforderlich wäre? Nur die Bürstenverbindung zu den Schleifringen?

Ich persönlich denke es könnte auch nur das grüne und blaue Kabel zwischen Stator und Regler (DF) irgendwie defekt sein? Eines der letzten Male, als ich dieses Problem bemerkte, schien das Entfernen des Bürstenkäfigs und das Wiedereinsetzen das Problem zu beheben. Obwohl ich annehme, dass dies Zufall sein könnte ...?


Neugierig, ob jemand irgendwelche Hinweise hat, bitte?








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Hi guys,


My charge light is sometimes very dimmly coming on when riding my 251. It's extremely dim to see it at all in the daylight, but I have a voltage output gauge that I've had strapped to the handlebar since 2016, so I can see when specifically the battery sometimes doesn't receive any charge.


So far I have replaced the brushes and brush holder. But I have also tried a different rotor too actually. The items themselves all look in fair condition and with good wear still remaining.

My next point to look at, although I have a feeling I have already tested it out breifly, is to change the voltage regulator. Currently I have got a solid state one which was on the bike when I bought it (has now covered almost 20,000 miles in my ownership, I have no idea how long the item has been on the bike before that) - though I have plenty of mechanical ones to try out.


However, part of me thinks it is not the voltage regulator, because sometimes the charging is intermittent, both starting/stopping whilst riding. And sometimes, it is a little gamble as to whether the red charge light will be illuminated when I turn on the ignition, sometimes it is not. So I don't think the voltage regulator itself would be required in that instance? Only the brush connection to the slip rings?

Personally I think it could also just be the green and blue cable between stator and regulator (DF) could be defective in some way? However one of the last time I noticed this issue, removing the brush cage and putting it back seemed to fix the problem. Though I suppose this could be coincidental...?


Curious as to whether anybody has any pointers please?

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

Vielleicht hat eines der drei schwarzen Kabel an der Anschlußplatte an der Lichtmaschine keinen guten Kontakt, die Lötstellen sind es manchmal. Hatte ich an der 251er meines Bruders schon mal.

Perhaps one of the three black cables on the alternator connection plate has not good contact, sometimes the soldering points are it. I had this problem on my brother's 251 before.

_________________
Grüße

Frank

Take a few voltage measurments and it will be easier to get a diagnosis. See here:
viewtopic.php?p=1696973#p1696973

Translated with www.DeepL.com/Translator (free version)

a) Ignition off: 6.2...6.4V or 12.4...12.8V . Values below 6.0V or 12.0V: Deep discharge and/or battery is tired or defective.

b) Only applies to original breaker ignition: Switch on ignition, voltage does not drop below 5.8V or 11.6V.
Values below 5.5V or 11.0V indicate a discharged and/or tired or defective battery.

c) Start the engine and bring it up to about double to triple idle speed: 6.9 ... 7.1 V or 13.8 ... 14,2V.
Values significantly below this: Regulator misadjusted or defective or generator defective.

d) Motor double to triple idle speed, switch on main headlight: 6.7 ... 6.9V or 13.4 ... 13,8V.
Values significantly lower: Regulator misadjusted or defective or generator defective.

_________________
MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

Hi,


Thank you for the responses. The bike does charge- but intermittently. Some miles I can have no worries, but then suddenly the charge light will be on, and as mentioned with the help of my voltage gague I can see that no charge is being provided. (hovering 12 volts), but charges at roughly 14v when it is charging.

I have changed the rotor with the slip rings and the brushes (and holder) thus far. I have also layed three new cables U, V, W in place of the original loom recently but that has given no resolution.

Thank you.



Vielen Dank für die Antworten. Das Fahrrad lädt - aber zeitweise. Einige meilen kann ich mir keine Sorgen machen, aber dann leuchtet plötzlich die Ladekontrollleuchte, und wie bereits erwähnt, kann ich mit Hilfe meines Spannungsmessers sehen, dass keine Ladung bereitgestellt wird. (schwebende 12 Volt), lädt aber beim Laden mit ungefähr 14 V auf.

Ich habe bisher den Rotor mit den Schleifringen und den Bürsten (und Halter) gewechselt. Ich habe vor kurzem auch drei neue Kabel U, V, W anstelle des ursprünglichen Kabelbaums verlegt, aber das hat keine Lösung gebracht.

Danke dir.

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

OK, do you have a real voltage display (DVM) on your bike which shows the voltage number from 0 to 14V?
If yes, maybe you can use it to isolate the malfunction: Apply the DVM to the plus rotor brush - so it will show you the actual exciting
voltage of the generator. While riding the voltage will fluctuate normally between a few volts up to 12V depending from electrical load
and rev number. Which value does the DVM shows if red charge control suddenly lights?

Regards
Lothar

_________________
MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

Hi Lothar, thanks for response. The problem is not one side nor the other, but that it the state of charge changes between sometimes charging, and sometimes not.

Yes, I have a voltage gauge/display. It is wired with the positive terminal on coil (for easy switched live), so it's not completely accurate but it is within a few hundred mA, and more importantly the voltage figures themselves RE small differences between 13.8-14.2v don't matter but I can see that it does start too charge from above 1400 as per usual giving up to 14v ish with revs increasing perfectly normal, when the vehicle decides it wants to charge.

Othertimes my display output on the voltage gauge displays anywhere between 11-12v depending on electrical load when the red light illuminates (very very dimly) when the vehicle chooses not to charge. So in short, I can see by the gauge and red light that I ride for 5 or so miles and I can see on the gauge roughly = 14v so = yes it charges. Then a few miles down the road I might see the display read roughly 12v- uh oh, no charge- and the red light is on dimly. And it may come in and out like that, sometimes not charging for 20-30 miles one day, but the next day it may charge the whole journey fine, or may come in and out.

I also have the added extra that sometimes when I turn on the ignition to start my ride, the charge light does not illuminate! But sometimes it does. That points to brushes, or regulator? Because that sounds like a connection issue at alternator to me, as opposed to the regulator itself? But the brushes pass their signal to the regulator first and then to the light from what I can see reading the diagrammes? So could still indeed be a faulty regulator..? Interesting to me.

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

This may be a possibility. Have you tried any other?

I think more that's the problem....



And first I would look at the fuse box. Is it the original one with "torpedo"-fuses? The fine-wire fuse (2A) for the generator could have connection problems.

_________________
Grüße

Frank

Thanks for suggestions. I have been through the fuse box, even replaced it so I don't think it is that. It already had a blade fuse box on but I tried another blade fuse box and it was the same.

Aha. So in my attempt to replace the regulator with one I know works, I had to move out of the way the electronic ignition 'box' that is mounted via the the main earth point adjacent to the terminal box on the air box. When I loosened the electronic ignition box, an earth wire came out despite not yet removing the bolt. The earth wire that came out was the one that leads to the regulator! (pictured is EI box).

So, it becomes apparent that I hadn't put the hold down bolt through wire terminal 'eye' and it must have been just squashed down there amongst the other earth wires, sometimes making a connection, and sometimes not.

As it is- I still replaced the regulator but i'll use the bike and keep a track of what happens. If all goes well, I'll reconnect the old regulator and that will confirm/deny the fault was with regulator or indeed as it seems merely this earth wire...




Thank you guys for all your help- I will follow up this thread at a later date to say whether it is fixed or not after some time riding..

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

Yesterday evening I looked at the 12 V circuit diagram and I also noticed the extra ground cable to the generator. And the main ground point on the chassis is also often the reason for contact problems. Glad you were able to find the error there. Have a good trip with the MZ!

_________________
Grüße

Frank

Ah.

So this has seemingly not been resolved by a different regulator and fixing the earth wire properly... The charge light came on briefly today whilst doing about 50mph (not that speed has necessarily ever been a connecting factor- just thought i'd point it out), for approximately 10-20 seconds. But this time had a bright red charge light as opposed to a dim one (maybe because it is dark, or indeed maybe because the earth is being properly utilised(?)). But then the light went out and I could see in my voltage display that it was charging and it continued to do so without interruption for the rest of the journey... Definitely looks like it will be a problematic one to fix, perhaps.


Would it really be one of the U,V, W wires or connections? I was under the assumtion that if one of those wire connections was interrupted somehow then the engine would act eratically at idle? Or would that only be the case indeed when the battery had been depeted- I think so. Perhaps the rectifier itself has dry joints with the diodes etc. But, if one of those connections was broken then I'm not entirely sure the charge light would be on in those conditions? But I think the next thing to check I suppose is the blue/green wire from generator to fuse box, then fuse box to regulator, including the connection at the fuse box..

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

I know it's been a long time coming- but I realise I need to update this thread. The problem I fixed a few weeks ago (i've barely put a hundred miles on the bike since the last post (i wanted to use other bikes instead), but in those small miles before retirement for a year, the problem was getting worse and worse and random in conditions) was a corroded terminal (previously the original terminal had been replaced with an aftermarket crimped item) and oxidised copper on the charge signal wire (DF) at the alternator end. Infact, it was very easy to simply pull the terminal away and the two strands of remaining green/black copper just snapped. The wire was stripped to shiny core and a new terminal soldered on (I know some don't like soldering, but I do). Which was the next easy logical thing to check as per my previous post.

There was continuity between the two terminals from altenrator to fuse box initially, but with the audible output on the ohmeter (digital display is too slow), I could hear that there were intermittent (just the smallest) breaks sometimes when manipulating the terminal/wire.

Since then I have had no issues concerning intermittent battery charging and the light coming on and I've put about 300 miles on.

_________________
1973 MZ ES250/2 - 18,000 miles
1979 Suzuki TS185ER - 10,000 miles
1981 Honda CX500B - 91,000 miles
1987 MZ ETZ300 - 40,000 miles
1989 MZ ETZ251 - 51,000 miles

Great that you were finally able to fix the error.

The problem with the solder joints is that they tend to break due to vibrations.

_________________
Grüße

Frank