New Dynamo, new Voltage Regulator, still not charging

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Alebulance Driver
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New Dynamo, new Voltage Regulator, still not charging

Post by Alebulance Driver »

Hi All,
I had a problem with the ignition warning light coming on on my 1970 1098 van, so after some faffing I replaced the dynamo, to no avail. I've just replaced the voltage regulator, again, the light stays stubbornly on. The engine runs fine, fan belt is tight, I've cleaned all the terminals with emery paper and renewed any dodgy looking spade connectors, still that light shines bright. With headlights on and revving there seems to be no change in headlight brightness. If I manually flick the right hand contact on the voltage regulator there's a spark and if I hold it closed the light does go out. So I'm thinking the new regulator needs adjusting (despite me checking with ESM that they come ready set up). Haynes is not much help - to me at least. Any ideas?
Thanks in advance,
myoldjalopy
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by myoldjalopy »

Did you polarise the new dynamo when you fitted it? That could be the problem.
Also, these new voltage regulators aren't the best - I've had problems with them in the past and its just possible the new one isn't working properly.
So, I would polarise the dynamo (if you didn't originally) and then check the dynamo is producing current. If it is, and all connections are good, I would suspect the regulator. If you need more help with polarising the dynamo or checking its output, come back and we can advise further.
Nickol
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by Nickol »

Also check the wiring between the Dynamo and the control box for continuity and that the wires are correctly attached to the F and D terminal.

It is a shame that you were not able to use this as a guide before replacing what may have been already good components

http://www.rjh-heritage.ch/index_htm_fi ... gnosis.pdf
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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StillGotMy1stCar
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by StillGotMy1stCar »

Ditto. Did you polarise the dynamo?
Easiest way to do this is use a new length of cable connected to the small terminal on the dynamo and with the battery earth terminal connected, flash the new cable to the other battery terminal a couple of times. Remove new cable and refit the original.
Regards John
Alebulance Driver
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by Alebulance Driver »

Thanks for the tips so far- I've now polarised the dynamo but it hasn't made any difference. I've tested the armature circuit on the dynamo and am getting 1.5v when I rev quite hard. Looking at the Lucas Manual that Nickol kindly attached, I can't conduct the test for the field circuit as I only have one meter. I think I've reached the limit of my expertise on this and I'm going to take it to a local expert tomorrow unless there's any more simple suggestions.
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by Nickol »

We are perhaps getting there. Assuming you have disconnected the F and D wires and joined them together with another cable, then if you have to rev very hard to get only 1,5V at the Dynamo itself. then there is something already wrong. At a fast tickover you should achieve about 3V and reving hard would top 15V, which is not a good idea to do as it can burn out the windings.

Test the Dynamo itself (albeit rather crudely) by removing the fan belt, pull off the F and D wires as before, join them with a separate wire - spring Clips on both Ends is a good temporary way. Then apply the cars 12V power source to this wire. Assuming your car is neg earth and the earth is connected, the battery positive is connected to this wire. The Dynamo should now spin relatively fast as a Motor indicating that it is working. If it does not, and you are sure that the power source is ok, then you have found your fault.
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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myoldjalopy
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by myoldjalopy »

As above, to test the dynamo but even easier as you don't have to disconnect/connect any wires, just slacken off the dynamo mounting bolts so the fan belt is really loose, remove the control box cover and, with ignition on, press down the cut-out contact (i.e. the right hand one of the two as you face the car). If the dynamo is good (and the battery charged) it will run briskly as a motor.
It is possible that your old regulator was faulty and damaged your old and new dynamos.....
DAVIDMCCULLOUGH
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by DAVIDMCCULLOUGH »

I had a new old stock regulator and it would not close to complete the circuit, there was a very fine film of dirt or rust on the points and once cleaned with very fine paper it started to charge. I had another new one and it had some sort of oily stuff on these contacts, again once clened it started to charge


Too many Minors so little time.....
JOWETTJAVELIN
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Re: New Dynamo, new Voltage Regulator, still not charging

Post by JOWETTJAVELIN »

The oily stuff is preservative applied at the factory so the contacts don't deteriorate in storage, like c.b. points needs to be wiped off with solvent before use.
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