TR Paul Posted January 11, 2020 Report Share Posted January 11, 2020 Good morning, hope the weekend's going well for you all. As you would guess from the title of this post, I have a problem with the charging system on TRoy, my 1970 TR6 pi: When you turn the engine on, the ammeter shows (-) discharge, and if you turn the lights on, they will be very dim. If you drive away at normal traffic speeds, sometimes (without you noticing it) the ammeter needle will eventually move into the + side of the gauge, but more often than not you have to 'give it some welly', or blip the throttle (to anywhere around 2500 -3500 rpm). One time this didn't happen at all, & I was stranded (around 7 miles from home) because there wasn't enough 'juice' in the battery to work the Lucas fuel pump. I was rescued by a very nice man from Brittania recovery, who strapped a battery booster pack on, which got me home, & less than 2 miles from home the ammeter burst into life, everything working as it should. I've had the alternator tested (it's a 70 amp unit from 'Minispares', about 3-4 years old), & it's in perfect condition. I've also ran a new cable from the alternator to the ammeter, but the situation remains the same. Any ideas....? As ever, your thoughts & advice, will be more than appreciated, Cheers, Paul, Quote Link to post Share on other sites
michaeldavis39 Posted January 11, 2020 Report Share Posted January 11, 2020 How old is your battery--I would check its condition as these days around 5 to 6 years is all you will get from one. Michael Quote Link to post Share on other sites
RobH Posted January 11, 2020 Report Share Posted January 11, 2020 (edited) Maybe not the battery. When the voltage was low there would be a full charge shown on the ammeter all the time, so from the described symptoms it sounds as though the alternator isn't always working properly. I guess the alternator was tested off the car Paul? If so there is a possibility that something in the car wiring isn't right which stops it operating. One possibility is that in order for the alternator to 'start up' there has to be a current supplied to it via the ignition light on the dash. If that connection isn't right or if the bulb is making a poor contact you might get the symptoms described. Some people have had trouble by swapping that bulb to an LED and have needed to put a resistor into the circuit just to provide sufficient current. Edited January 11, 2020 by RobH Quote Link to post Share on other sites
TR Paul Posted January 11, 2020 Author Report Share Posted January 11, 2020 (edited) Thanks for your replies, Michael & Rob: a couple of interesting points there..... The battery is 3 or 4 years old, & always holds a good charge between using the car (sometimes upto 2 weeks, at this time of year), but I did forget to mention in my 1st post, that when this problem first arose, the ign light (which is the standard item, no LEDs or anything; I've certainly never changed that bulb, in 12+ years that I've owned the car.) was very erratic, & now it doesn't work at all..... Cheers, Paul. Edited January 11, 2020 by TR Paul Quote Link to post Share on other sites
Waldi Posted January 11, 2020 Report Share Posted January 11, 2020 I would follow Rob’s lead. If you have a multimeter, you could measure the voltage, it will give you a good indication. And are the connections to the amp gauge, generator, starter motor (yes) and battery all sound? Waldi Quote Link to post Share on other sites
TR Paul Posted January 11, 2020 Author Report Share Posted January 11, 2020 Thanks, Waldi; my first check will be the charge lamp, & the relevant connections, followed (if necessary) by a session with my multi meter. Best wishes, Paul. Quote Link to post Share on other sites
Mike C Posted January 11, 2020 Report Share Posted January 11, 2020 I'd go straight for the multimeter. If your battery's getting over 14V at , say, 2500 rpm there's nothing wrong with the charging system. If your not getting this I'd check/change the ignition light bulb. Weird as it sounds today, my '69 PI needs the current through this light to energize the alternator windings. Quote Link to post Share on other sites
TR Paul Posted January 12, 2020 Author Report Share Posted January 12, 2020 (edited) Thanks, Mike. I was going to look at the bulb first, as this would be the easiest fix (although that kind of thing doesn't usually work out like that for me...). Hope you are keeping safe in 'Oz', Best wishes, Paul. Edited January 12, 2020 by TR Paul gramatical! Quote Link to post Share on other sites
Mike C Posted January 12, 2020 Report Share Posted January 12, 2020 OK now, but on the 4th the Euroa fire in Victoria got to within 350 metres of the garage with my TR in it, not to mention the house. Still all's well at the moment. Be careful with the bulb holder when removing the globe, the old plastic insulators that were in these are getting brittle. Last year I broke the plastic insulator base when changing a tacho illumination bulb - had to remove/replace the tacho to solder in a new bulb holder assembly-which is a horrible job in my car as there's a reinforcing plate fitted above the steering which blocks access to the back of the tacho . Quote Link to post Share on other sites
TR Paul Posted January 12, 2020 Author Report Share Posted January 12, 2020 Glad to hear you're ok, Mike. Our thoughts in England are with our Australian friends. I did some investigating this morning, & found that it is indeed the bulb/bulb holder... if you gently push the bulb into the holder, it lights up. if you pull it, it lights up. But I don't think I can rely on it to maintain contact. I fitted it back into the r/counter, & with some fiddling, it would come on. I then started the engine, & hey presto, an almost instant + charge on the ammeter! Problem is, the bulb seems to be stuck the holder, so I can't change it or clean it up, tweak the contacts or whatever.... Does anybody have any tips on bulb removal? Cheers, Paul. Quote Link to post Share on other sites
Waldi Posted January 12, 2020 Report Share Posted January 12, 2020 The Bosch part no of the alternator I have installed is: 0986.036.020. But there are several very similar alternators from Bosch, all with the same capacity and "fitting" dimensions. Waldi Quote Link to post Share on other sites
ntc Posted January 12, 2020 Report Share Posted January 12, 2020 I would invest in a Ctec charger and condition the battery first. Quote Link to post Share on other sites
Mike C Posted January 12, 2020 Report Share Posted January 12, 2020 4 hours ago, TR Paul said: Glad to hear you're ok, Mike. Our thoughts in England are with our Australian friends. I did some investigating this morning, & found that it is indeed the bulb/bulb holder... if you gently push the bulb into the holder, it lights up. if you pull it, it lights up. But I don't think I can rely on it to maintain contact. I fitted it back into the r/counter, & with some fiddling, it would come on. I then started the engine, & hey presto, an almost instant + charge on the ammeter! Problem is, the bulb seems to be stuck the holder, so I can't change it or clean it up, tweak the contacts or whatever.... Does anybody have any tips on bulb removal? Cheers, Paul. Thanks for the support. Have you tried spraying the bulb in its holder with something like WD40 and leaving it for a while to soak in? Quote Link to post Share on other sites
Waldi Posted January 13, 2020 Report Share Posted January 13, 2020 Or even better: electric contact spray. Quote Link to post Share on other sites
TR Paul Posted January 13, 2020 Author Report Share Posted January 13, 2020 Thanks, Waldi/Mike... I sprayed plus-gas on it this morning. Cheers Paul. Quote Link to post Share on other sites
Nobbyc Posted January 14, 2020 Report Share Posted January 14, 2020 just break the glass and use a screwdriver Quote Link to post Share on other sites
Mike C Posted January 14, 2020 Report Share Posted January 14, 2020 36 minutes ago, Nobbyc said: just break the glass and use a screwdriver If you do this you need to be careful of the insulator base. After 50 odd years they're pretty brittle. Quote Link to post Share on other sites
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