Ignition Light

[Paddy]

Ok, so having replaced the dynamo (after finding old 1 was making that noise (posted in other thread)) now i have the problem... fan belt has about 1/2 inch play in between dynamo and fan pullys.... the ignition light goes out when started as it should. however when i rev the engine the light comes back on?? and then fades out when i stop revving??? im thinking of upgrading to an alternator soon anyway, however i want to get this sorted before i do.

any help much appreciated
thanks
paddy

[Hubert64]

Hello,

I have exactly the same problem with my HA of 1965. Have you found out what was wrong ?

I'd be very interested to know what should be done to cure that problem without converting to an alternator.

I'd prefer to keep the dynamo.

Thanks for your attention.

Hubert64.

[1972nail]

You have a seperate voltage regulator somewhere in the charging circuit, but not knowing much about HA anatomy I don't know where or what make it might be.

Anyway, it is probably a mechanical regulator with coils and points inside it. What has probably happened is that the points have got a bit burnt and dirty over the years and need cleaning.

Disconnect the battery.

Use very fine emery paper, P400 or finer, and GENTLY wipe it between the points. Then dip a clean tissue in acetone or nail polish remover, if you have some to hand, and gently clean off any dust and wipe between the points again.

[Hubert64]

Hello 1972nail,

Thank you very much for your awnser.

The regulator is a Lucas control box that is positionned behind the grill, near the left hand head light (seen from driver's position).

I will do what you suggest as soon as possible and inform you of the results.

Thanks again,

Hubert64.

[1972nail]

There are a number of connections to the control box. These could also be corroded. Easiest way to clean them is to use some citric acid, available from any cookery shop, brushed on with a toothbrush. If you can, immerse the loose ends of the wires for a few minutes.

[Hubert64]

Hello 1972nail,

This week end, I did exactly what you advised (cleaned the points of the regulator unit - not a Lucas by the way but a new unit without any make mentionned) with 400 grit paper then with a cloth and acetone) and the result is perfect. Now the ignition light doesn't go on any more when the speed of the engine is above idling. Thank you very much for your explanations that helped me solve the problem.

Hubert64.

[Fred Dukes]

RESULT - I can see someone taking on the role of Technical Expert

[1972nail]

Hello 1972nail,

This week end, I did exactly what you advised (cleaned the points of the regulator unit - not a Lucas by the way but a new unit without any make mentionned) with 400 grit paper then with a cloth and acetone) and the result is perfect. Now the ignition light doesn't go on any more when the speed of the engine is above idling. Thank you very much for your explanations that helped me solve the problem.

Hubert64.

I'm glad that my diagnosis (or was it a wild guess?) was correct and you found the recommendations easy enough to follow. I had the same problem a few years ago with our Morris Minor when my late Father-in-Law was my 'Technical Expert'.

[Hubert64]

Hello,

Here are a few informations that could help to solve the problem.

The regulator box for a Ha is Lucas RB340 12 volts from 21 to 23 amps.

1) Go on google and search "Lucas RB340".

You will see an entry "Lucas Generator and control box tests".

Open it and you will find the manual edited by lucas that explains the course you have to follow to discover the cause of the problem and it's remedy. It is very well done and you have to follow the sequence carefully. You'll also need a voltmeter that goes at least from 0 to 20 volts and an ammeter.

2) You can also go on google and search "www.spitui.com" and you'll find an adress called "testing voltage regulators". Open it and you'll find useful tips.

In a book about car care dating of 1962, they recommended to always have a spare regulator box in the boot. Spare regulator Lucas RB340 control boxes are easily available on internet or on ebay. I've purchased one from greenspark but haven't tried it yet. Be sure to verify the amps (21 to 23) before buying because some RB340 can handle less amps.

I hope these informations can be useful.

Hubert64.