Charging Circuit: symptoms of insufficient charging

[ssimm]

107,000 km still rolling down in France, but it died on me, twice, at speed, on a secondary road.
1. sputters and dies
2. wait five minutes, restarts, barely
3. runs 5km then dies
4. wait five minutes, can't start electrically but can bump start
5. runs 2km then dies
6. no method of starting works

Got a new battery between these two incidents. After the second incident I did the following tests, after recharging the
battery.

Motor cold, ambient temperature 7°C
12.9 v across battery terminals
14 v engine running, no load, at 2000rpm
Alternator/Stator:
Resistance between the white wires from the alternator, at the regulator harness: 1.9ohms, all three
Voltage AC between same: 30v at 2400rpm, all three.
Voltage varied with rpms. (don't have additional numbers but seemed linear)

Topped off battery on trickle charger overnight.

Motor after 15 min. runabout keeping the engine mostly at 5000-6000rpm , ambient temperature 14°C:
Across battery terminals:
12.0 v engine stopped
11.83 v engine stopped, high beam on
11.45 v same plus brake and hazard lights. (.2 variation with blinking)
11.85 v running, no load, 1000-5000 rpm (i.e. no variation with rpms)
Alternator/Stator:
Resistance, as above, 1.4 ohms, all three
Voltage AC:
15 v at 1000 rpm, all three
33 v at 3000 rpm, all three
48 v at 4500 rpm, all three

Rotor looks ok visually (did not remove it, just removed the cover)
Regulator looks ok visually (did not remove it). No stange smells immediately after the runabout.
Battery voltage 12.1 one hour later.

My suspicions:
2nd battery seriously weakened by 2nd incident
1.9 ohms is bad, but is it so-so-just-keep-the-battery-charged bad, or is it baaaaad?
The regulator malfunctions after warming up

Any suggestions?
I'm hoping to keep using my old horse but new pollution requirements will make it verboten in a year, sniff sniff.

Thanks, much obliged!




97 XJN 600 for ten years
97 XJS 600 now

[spike240]

Wow. That is a lot of testing. I can't give an opinion about you test results, but if it was me I would look for a replacement regulator first, and maybe an alternator.
Good luck & all the best.

[m40man]

Points to just the regulator/rectifier to my mind.

[ssimm]

I ordered a regulator. Stay tuned for further updates.
BTW I searched around a bit on the forum but couldn't find any details about the a tool to pull the stator (if it comes down to that).
I see things like "fits Diversion" on the interweb, but what should I look for if I order such a tool?

Thanks, love this forum!

[m40man]

Apr 5, 2022 16:15:54 GMT ssimm said:

... couldn't find any details about the a tool to pull the stator (if it comes down to that).
I see things like "fits Diversion" on the interweb, but what should I look for if I order such a tool?

I overlooked this - sorry!

By now you probably know if you need a new stator or not. The only time I've removed one (on my CB750) I used the percussive method, because my only immediately available puller couldn't get purchase without risking damaging casings.

So if you're interested, here's the thread which illustrates the method .... (along with various folks questioning my capabilities & my sanity as I rushed to fix it for an up-coming Jock Run!)

diversionclub.proboards.com/thread/22050/?page=2

[ssimm]

I'm back with the results of a new regulator, and it seems it was the regulator that was dying slowly.

After a 35 min. hard run (same behavior as previous run) I got these differences compared with previous tests with
the old regulator:
14.5v across the battery terminals while running (instead of 11.85) , no load, 1000-5000 rpm (i.e. no variation with rpms)
Battery voltage 13.8v one hour later.

I pronounce it fixed.

Obviously the alternator is getting old, 1.9 ohms is not normal. But I can live with that for now.

I saw the "special tool" photo. When the tool is wedged in there what is it wedged against, the inside of the rotor or the axle? And the blows, did you hit the top of the axle "staight", so to speak? Or at an angle?

Thank you all for your help. BTW I did the big remove-the-winter-crud cleaning this weekend, and hey! There's faring and chrome and all kinds of stuff underneath!

97 XJN 600 for ten years
97 XJS 600 now