Am I right in thinking that worn alternator bushes or a slipping belt would not normally turn the amp light on? Mine came full on yesterday (122S 1967 but with alternator) and I'm trying to start with the most obvious when I trouble-shoot.

Should I start with alternator mountings, connections and grounds? Then do a system charge test. What's the expected result on our older Volvos? About 13.5 - 14?

I live in rainy London and it came on in the rain, if that's any help.

Thanks a lot.

Tom

Either the belt or brushes could cause that. Check the belt first, as that's easy (but you'd probably hear it squeak). Second would be brushes... usually the problem with them old generators, and they are relatively easy to replace.

Of course, wiring is also a distinct possibility, but my money would be on worn brushes. Could be a worn out generator too. Bad commutator.

Being in the UK, brushes should be easy to source...

--
-Matt '70 145s, '65 1800s, '66 122s wagon, others inc. '53 XK120 FHC

It MIGHT be the brushes but I would check the fuses first, especially if
the turn signal seems to be involved. They are famous for that.
--
George Downs Bartlesville, Heart of the USA!

I have a 68 wagon, when it sits for a few days I have the same problems. Just spin or take the fuses out and put them back in again.When this first happened I thought all the worse, brushes / bad gen./voltage reg./ belts. It seems to be the short one on top.