flickering battery light / replace regulator?

[Middle29]

Just had some work done, new manifold gaskets etc. Also couple of pulleys replaced and new belts etc. I now have a flickering battery light. Assumption is that the belt is tight enough, Bluetooth battery monitors tell me both batteries are charging. About 13.75v on starter and 13.25v on leisure with headlights off (but I would need to double check as it was a quick look after drive home from work). I'm planning to check wiring today in case something is obvious / loose. I understand alternator regulator is a quick/cheap fix.

3 questions:
If the charging voltage is dropping when headlights are on does this indicate regulator is not doing it's job?
Are regulators specific to alternator models?
Anything else I should be looking for while I'm in there?

Thanks

[ZsZ]

Voltage shpuld be more close to 14V measured to battery. Those numbers look really low.

We can assume the alternator is not charging.

Check the D+ (blue) wire. Corrosion or partly broken wire could cause the alternator not being excited.

[Middle29]

thanks - so blue cable was crimped to another and I had to remove insulating tape to check which one went to alternator and also see if there was a problem with the crimp. In process blue wire just fell out of the plug on the alternator.

So question is can I fix that wire back in or do I need a new part that has a couple wires that need crimping again?
Apparently this is correct part: https://www.autoelectricalpartsuk.co.uk ... lug-PL24WL

[ZsZ]

You could de-pin the old connector and crimp/solder on a new one, but it is more convenient to buy a new connector pigtail and crimp/solder the wires together.

The connector should come off by pressing in the metal locking ears on the side and pull the connector.
Try to spray some WD40 or similar to where the connector meets the alternator

[Middle29]

Thanks for the feedback, I've ordered the new part, excited to see 14v

[ZsZ]

Hopefully the connector on the alternator is not too damaged.

[Middle29]

So I've got old one off eventually, I'm picking up some crimps to put the new one on. But I'm guessing the exciter from starter and blue to dash are not really going to have much effect on my charging voltage is it? Or are these linked in with the regulator in some way I'm not aware off?

I guess I'll find out but if so, is next step an alternator refurb or can you swap out regulator or something without removing belts etc.

[ZsZ]

The exciter circuit (dash light) gives power to the outer coils. Without that the magnetic field cannot build up (excite) and the inner rotating coils not generating power.

[Middle29]

oh ok that is good news then - thanks so much for explanation.

[mioba]

Better to solder than use crimps with tail wires. Then some heat shrink.

Very common on T25 for the cable connectors to drop off. The wires are old and brittle.

Went through my engine bay last year and opened all connections, wire brushed clean all connections reseated and greased.

Had at least two wires fall off the crimps when doing so.

Good luck - keep us posted

[Middle29]

So only just seen this but I'd already crimped them up this evening. Dash light is not flickering now but..

Starter was sitting at 11.44v and leisure at 11.90v before I started up. - It's been sitting in the garage for a 3 or 4 weeks so batteries might be a bit knackered.

Charging voltages got to about 13.52 starter / 13.14 Leisure. Headlights affect charge rate. I am measuring using 2 bluetooth battery monitors across each batteries terminals and an app so maybe not ideal?. I have a meter but only semi confident using it.

I've read a few posts about checking wiring contacts, grounds etc. and replacing brush pack as it's relatively straightforward.

Whats best order of diagnosis / work etc?

And how do I ascertain which brush pack to purchase?

If I have original brush pack in there would 13.75v be about right? I have been reading about 14.5v brush packs to get that extra .5 to 1v.

Thanks, I appreciate the responses.

[ZsZ]

11.44V is a really low battery. They might be damaged being not charged properly for a long time. Try to charge them up with a mains charger first.

[mioba]

Just go through the connections in the engine bay take them off wire brush and put back and grease them.
Same for all earths too.
The regulator seems fine if running with headlights on - just turn the blower on to see ot drop. Best measure with all accessories off.
I use a USB charger to replace the lighter socket instead with a built in Voltmeter. one of the best upgrades.
BW for any parts you need.
These are simple machines to work on. Use hear shrink on the connectors to keep them clean and the moisture out

[Middle29]

So as an update. I cleaned up all contacts on both batteries, Alternator, alternator ground to engine block and ground in leisure battery bay.
Took out and charged both batteries.
Just took it for a drive and I'm getting 13.61 to starter and 13.02 to leisure.

So much improved but maybe not as high as I was hoping. I'm guessing brush pack / refurb alternator if I want more?

Temp gauge has stopped working and gear linkage is playing up now but I'll start another thread. When ever something gets fixed it seems to come back with new issues

[Middle29]

So I'm still getting fairly low voltages when charging13.30 on starter below 13 on leisure.

I'm guessing next step is the alternator. I have a local man that refurbishes alternators. So I can either attempt to swap brush pack in situ or remove alternator and take to him to refurb (or swap brushes myself of course).

I've not done either of these before, what would be the easiest out of these options? Removing alternator or replacing brush pack in situ? 

It's an AAZ engine.