Flickering volt meter????

[Thegoverner1965]

Hi all,well after a couple of months my first problem had occurred .the volt meter always used to work correctly but has now started to flicker.although this is annoying it was still accurate regarding the battery's condition.over the last couple of weeks it has gone from the green area into the yellow area.also my journey home today was worrying as it was slow to start.when I checked the battery using a tester is was in the middle of very good ,good and poor.as this gradual battery charge loss has occurred I assume my dynamo or regulator are at fault.i replaced the dynamo with a unit that came with the car but it still did the same thing.so I assume both dynamos are broke????
Thanks for your help
John

[mogbob]

John
With the battery disconnected ,I'd work systematically through your electrical connections making sure they are clean ( bare clean metal on the terminals) and secure.

Back of your volt meter, wires /terminals on the dynamo and regulator, check the fan belt is tight ( not sloppy -check workshop manual ), battery connections, good earth point to body and also the gearbox to bodywork earth strap. Clean the terminal ends on the battery to solenoid thick wire.
Possible causes : -
It could be that your battery is knackered, do you have a battery charger to "top it up " ? See how long it holds it charge
before needing re charging ( and possibly eventual replacement. )
Dynamos...maybe the "original " failed because of worn bushes and was replaced with the one you had on the car.
Does your ignition light flicker at tickover as well, it could be that the replacement dynamo's bushes have worn out as well
( depending on the miles covered ). Replacement of the bushes isn't too difficult and won't cost you a fortune.

First check with a multi meter on the battery ( not a battery tester, which will check it, whilst it is static usually ) whilst the engine is running at idle. Meter set to Volts DC observe reading at idle and then see what reading you get when you rev the
engine on the carb throttle.( Keep well away from the fan belt and fan and don't have any loose clothing flapping in the breeze !! ).If the charging system is working OK , you should see it , the voltage climb to 13.5 to 14 + volts.

It always difficult coming up with the correct answer immediately as there are so many variables. So eliminate the easy / no cost bits and look at the indicators and report back.The guys on the forum will crack it for you.

Welcome to the Forum by the way.If you flag up your location ( just your nearest big town, not full postal address will suffice ) on your log in personal details , may be someone " local " will stick their head under the bonnet for you.Joining the local group will give you a lot of support.

Bob

[bmcecosse]

It's a big job to change the dynamo bushes (sic) - I would inspect the carbon brushes first and renew if necessary. Cheap and easy to do. But the problem may be in the Regulator - the 'pulsing' suggests that as it cuts in and out. I assume the fan belt is tight enough?

[Sandun]

check ur volt meter , is it fine ? -Ok remove the dynamo connection from ur car- take 2 wiers and set it dynamo 2 out put , then end of the 2 wiers joint them together - start ur car and speed some, next the wire short with the car body , if ur dynamo good u can see good spark - if it is yes not remove dynamor from ur car - has ur car Ampermeter ? If u have ,u can see how to work ur reguletor box - ok remove testing wires and re set wires of dynamo again to ur car - remove reguletor box cover , start ur car and speed, if the point of reguletor moveing when u speed the car ,ur reguletor is fine - check ur battery