Charging light & idling speed

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Julian B
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Location: W Sussex, UK

Charging light & idling speed

Post by Julian B »

I have been lent an electronic timing light with a digital rpm read out by John (many thanks, John!), and my idling speed on my green Haf was - as he suggested - FAR too high. I adjusted the carb to get it to what the book says that it should be, ie ~700rpm, but at that speed it sounded a little bit rough. Increasing it to maybe 900-1,000 was much better. However, my charging light on the dashboard only goes out at ~1,400rpm, which is therefore a bit too high. Is this normal? If not, is there anything that I can do to make it charge at a lower rpm - ideally ~1,000?

TIA

(As an aside, the timing light has shown that my governor does kick in at ~4,500rpm. Good news!)
Julian B
W Sussex, UK

| '62 Early Series I SWB | '72 Series II LWB |
| '56 Citroën Traction Avant |
HaffyHunter
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Location: Canada

Re: Charging light & idling speed

Post by HaffyHunter »

Hi Julian,

There is a procedure for testing and adjusting the voltage regulator output in the repair manual.

It is normal for the indicator to be lit when at idle speed. My light goes off at a bit over 1000rpm, likely between 1200-1400rpm, can't be more precise than that as I've not paid close attention to it.

Cheers,
Steve
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heinkeljb
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Re: Charging light & idling speed

Post by heinkeljb »

My charge light is also on when idling, and goes off as the engine revs rise. Must admit I haven't done the test you have done Julian, of using the strobe / rev counter to measure the speed at which the light extinguishes.

In fact it is more important at what voltage it extinguishes as this has more bearing on the state of charge of the battery. Seeing as the two thing are tied together, following the guide in the manual should allow you to set the regulator so that it starts charging (light off) at as low a speed as possible, but I doubt it will ever be at the lowest revs (~700) far more likely that at 850 ~ 1000 rpm is the optimum point.

John
Haflinger 703AP LWB 1973 - (Once owned by Lady Sutherland & Sons.) Now called "Lurch" !

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AustHaflinger
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Re: Charging light & idling speed

Post by AustHaflinger »

Julian - my engine idles at 1000 rpm and the charging light is on - it goes out at about 1200 - 1400 rpm so you experience would seem to be quite normal.

Garry
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Julian B
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Re: Charging light & idling speed

Post by Julian B »

Thanks for the replies, all. I will re-set my idling speed to 900-1,000 rpm, and stop worrying about the charging light coming on at idle. Seeing as I almost never use the headlights, rarely use the wipers, and always leave it on an Accumate charger when not in use, the charge in the battery should be fine anyway.

Fiddling with the voltage regulator is probably something for another day; I have no evidence of the charging system being anything other than fine, so I'll follow the old adage of If it ain't broke, don't fix it ;)
Julian B
W Sussex, UK

| '62 Early Series I SWB | '72 Series II LWB |
| '56 Citroën Traction Avant |
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