Dynamo connections

[A&P Minor 1967]

Hi,
Brand new here, first Minor ever and no technical/electrical hero Dynamo broken.
Old dyn is C40 part n° 22704J, New one is C40AQ part n° 22791/05
Car is pos. earth, on the new dynamo is written neg. earth
So changed the dynamo but now ign. light doesn't work and dynamo gets warm or rather hot... I removed the connectors
I suppose it has to do with pos. and neg. earth...
Green/Brown lead goes from F to the small connector.
Yellow/Brown lead goes from D to the bigger connector.

Do I simply have to switch the two leads on the dynamo or are there other things I should do ?
What is F and D standing for ?

Thanks for your help !

Greetings from a rainy Belgium
Peter

[bmcecosse]

NO - don't swap connections! Do you want to continue running +ve earth - or do want to swap to -ve earth?

[A&P Minor 1967]

If I understand well there are two options :
- a rebuild of the old dynamo
or
- change to neg. earth

Other things I'll have to do to pass the Belgian MOT are, change to LHD headlights and install a rear fog lamp.
Thx !

[bmcecosse]

No - if you want to stay +ve earth then all you have to do is re-polarise the dynamo. To do that - you need a length of cable - bare one end and connect to the small terminal on the dynamo. Then 'spark' the other end of the cable against the battery -ve connection a couple of times - hold it on for say 2 seconds after the sparking. Then reconnect the wires - and it should now charge !

[A&P Minor 1967]

I'll give it a try tomorrow ! Thanks for your help !

[mike.perry]

LHD headlights are available from most suppliers and if you have to change then take the opportunity to upgrade to Wipac Quadoptic halogen headlights.
You should be able to clamp a rear fog light under the back bumper and take the supply from the headlight wire on the light switch. Use a fog light switch with a built in warning light.
Are rear fog lights compulsory on early cars in Belgium?

[A&P Minor 1967]

Re-polarise is done but sparking was very poor. Dynamo doesn't get warm anymore so I suppose it is charging. On the other hand the ign. light still doesn't work.

Concerning the fog light
In Belgium we've got 2 kinds of numberplates:
1) Oldtimerplates : plate starts with O.... or 1-O....only allowed to drive during events or in a range of 25km around your house and never in the dark. MOT every 3 years.
2) Normal plates : for all other cars or for oldtimers wishing to be driven anywhere at any time. MOT every year and then a fog light is needed

[mike.perry]

Switch the headlights on and rev the engine, if the dynamo is charging the lights should glow brighter
Have you checked behind the speedo to make sure that the ign light is still plugged in or that the warning lights are in the correct places. Check ign light bulb.
As I already have rear fog lights I think that I would go for the normal plates otherwise I would not be able to drive the Minors to club meetings which are over 25 kms away and in the dark.

[bmcecosse]

You may have damaged the regulator or the dynamo running it wrong polarity - especially with the dynamo getting warm. The red light MUST go out - or it's not charging. Check connections. If it's still not right you need to test the dynamo.... Remove fan belt, remove connections. Length of wire - connected to BOTH the terminals and then touch the end to the NON earth terminal of the battery - the dynamo should run as a motor. Does it??

[A&P Minor 1967]

Dynamo runs like a motor but points of the regulator burned... To be continued next weekend

[bmcecosse]

Ahhh well at least the dynamo is fine ! Just clean the points very carefully with fine sand paper.

[A&P Minor 1967]

Points are really burned and are stuck. Sanding paper is no option anymore I'm afraid.
Concerning the ign.light, took away the glove box and bulb was not inserted in the back of the speedo... so is normal that i couldn't see the red light... have to test again when regelator is back in place.
Next problem is the ign.switch, it is not properly fixed to the dash. Hard to see what is missing to fix it, a kind of clips i suppose. Better to take the speedo out for a better acces ? Best way to take speedo out ?

Thx !

[bmcecosse]

Do you have a workshop manual????? Speedo out - screws at each side - slacken slightly through holes in glovebox - and pull!

[mike.perry]

The ignition switch has a threaded nut behind the panel and the chrome threaded ring in front. Put a screwdriver blade in the slot and turn clockwise to tighten.

[A&P Minor 1967]

What did I do:
Regulator replaced
Bulb ing. light replaced
Result:
Ing. on... red lights up, engine start and 2 seconds later... red light goes out
think it's fixed

Thanks for your advice and extra info bmc and mike !!


"The ignition switch has a threaded nut behind the panel and the chrome threaded ring in front. Put a screwdriver blade in the slot and turn clockwise to tighten." Mike you really mean to put a screwdriver blade where normally the key goes in ?

[mike.perry]

No, put a screwdriver blade in the slot in the chrome ring, unless the ring is missing, and keep your fingers out of the way.

[A&P Minor 1967]

Thx Mike, tried several times. Yes seems to fix but when i turn the inginition key to the left to stop the engine the ring turns also and i'm back where i started... Will try again.