How far am I likely to get with no charging? My Alternator (16ACR) has failed, the spare is also kaput and the one I just bought today from the motor factors (old stock LRA100) seems the same. Ignition light just stays on and no charge at battery. I've checked leads and connections, even made a new charging lead and connected straight to battery. Seems a bit suspicious though that 3 alternators have the same issues.
I have two charged batteries and need to make a 150 mile journey tomorrow and more during the week but will be able to charge batteries then. I plan to get another alternator as I can't get to return the one I bought until next weekend.
Will I make it?
It should be fine as long as you don't need to restart often or use the head lights.
Just running the ignition doesn't use much power at all, it's starting that sucks it up.
"Once you break something you will see how it was put together"
Thanks Marky, I'll give it a go then. I run a mechanical fuel pump but may need side lights early on. So I guess a few amps for 3 hours should be ok. My only worry is if the volts start to drop too low. Tomorrow will tell.....
Just checked everything is topped up before setting off and did a final check on the wiring at the alternator end ready for another alternator next week. With ignition off I have 12V on the main charge lead at the alternator plug so that is ok. WIth ignition on I have ~9V on the indicator lead at the alternator end. This should be 12V as well. Would this stop the alternator charging?
Well, problem gone. Two minutes into my journey the alternator sprang into life. When first installed I'd revved up to 3,000 rpm and still the warning light stayed on so why it should suddenly start working I have no idea. Alternators have just started working for me, never had to "run one" before to get it going. Anyway, will still have to investigate the low reading on the indicator lead but all working now.
Just got to offload all these spare charged batteries now.
Well, just thought I'd post an update on the problem with the low voltage at the alternator IND lead. This was showing under 9V with ignition on and the alternator wasn't charging until over 2000rpm. After a browse on the internet the problem was traced to the warning light. Someone in the past ( ) had replaced the bulb with an LED. Apparently this can cause the low voltage on the IND terminal and consequently the Alternator doesn't start to charge until revved up. This was probably what made me think my spare alternators were dead so time to check them again....
Good find - but my Lucas alternator charges away quite happily without the Ign wire being connected - as I found when the wire broke off at the terminal, and didn't bother fixing it for couple of weeks.
Credit goes to the guys who understand how an alternator works far better than me.
MR BMC, maybe you have one of those self exciting alternators? I checked on mine and if I unplug the IND lead I get the same problem as with an LED indicator bulb i.e. no charging until at least 2000 engine rpm. It seems you can get these led bulbs to work the same as a normal bulb but with added 'resistance' which I can't be bothered with...
I suppose there could be that '2000' rpm cut-in on mine - I never really noticed - just as along as it charged, I was happy to leave it be until I had time to deal with it.....
) had replaced the bulb with an LED. Apparently this can cause the low voltage on the IND terminal and consequently the Alternator doesn't start to charge until revved up. This was probably what made me think my spare alternators were dead so time to check them again.... 
