dynamo query

[rae80inch]

before I start I have a query about a charging problem on my tef fergie I know its not a morris minor but iam in the morris club now and I need to get it going so can sell it to fund morris project I got my spanner stuck on the two terminals on the amp gauge thers was a lot off sparkes and smoke and now there is no output on the dynamo I put a live feed to poll f to change polarity but no go is there anything else I can try or have I blown up the dynamo this is such a great forum I no someone will help thank you ,rae

[MarkyB]

Are you sure it's a dynamo? If it's an alternator, it's toast.
Cast iron case= dynamo, aluminium=alternator.

[rae80inch]

yes dynamo new last year

[MarkyB]

How long was it cooking for?
I'd try replacing the wire from the gauge for starters.

[rae80inch]

theres nothing comeing out off dynamo I was wondering is there a way off fixing it

[bmcecosse]

Spanner on the two terminals of the amp gauge should not have made any sparks - what really happened? Was the spanner also touching metal bodywork ?? Is everything else working?? Take the belt off the dynamo -and remove the wires. Join both terminals together with a bit of wire and then touch that to the non-earth terminal of the battery - if the dynamo is good - it will run as a motor. More likely something has happened to the regulator rather than the dynamo - but do the dynamo test and report back.

[rae80inch]

yes could off touched body all happened very quick ive got muti meter on the dynamo and nothing comeing out I will try the motor test tomorrow night and report back thank you ,rae

[rae80inch]

i tried the dynamo trick it worked it run like a motor I got in to the regulator if I held one off the bobins in I could get it to 12.4 volts but wire A on the regulator the one that comes from the live starter motor and goes thru volt meter gets red hot and is melting the wire had to disconnect the power now any more idea thank you ,rae

[bmcecosse]

Well at least you know the dynamo is ok! So your dead short has probably ruined the regulator -or the wiring to/from it. But you now mention a voltmeter?? When before it was an ammeter??

[rae80inch]

yes sorry I meant ampmeter so does that mean ive got a short on the a wire somewere

[MarkyB]

The smoke was from insulation cooking so a short is quite likely.

[rae80inch]

could this be from the regulator not working properly as I don't want to buy another one and fry that one aswell ,rae

[bmcecosse]

Remove the regulator - and look at the connections underneath the base - have they melted? And are the contacts on the reg welded together?? And trace all the wires to check for damage. This a disadvantage of an ammeter - it's not really possible to fuse the cable - although a commercial 60 amp fuse could be used I suppose.......