Ammeter of morris minor 1000

[Sandun]

Dear Sirs, Ammeter (Ampere meter)of my morris minor 1000 car Reading like this
when start the car,Ammeter is ''0" position
When all light on (still start ) -15 position (when engine raise it come "0" ......+)
All light off ,When Start and raise the engine +30.........(over then +30) Battery is ok (not low) (Ammeter is -30 - +30 Meter)
When full raise, battery voltage is 13 ,13.5
Voltage control box ------ I remove the A1, A wires and joint them together and check voltage between D and E before close the point it was 8v , Then raise the engine full and check voltage between D and E it was 15 or 15.5
the car uses Dynamo System

please tall me what is this abnormal reading of ammeter

[MarkyB]

From memory they sound fine, When full raise, battery voltage is 13 ,13.5 suggests it is charging OK.
Are you having starting or other electrical problems?

[mike.perry]

You have not said if you have a dynamo or alternater.
If you have a dynamo then the ammeter should show a small + when driving with the headlights, heater and wipers switched on.

[bmcecosse]

It's fine -except for the +30 reading when running with no lights on..... Does this reading reduce after a few minutes - or does it stay up at +30, which is obviously far too high, but is ok for a couple of minutes after starting.

[Sandun]

Dear Friend MarkyB it is a dynamo

[MarkyB]

Are you having a problem with the car or just checking things?

[bmcecosse]

His coil was overheating - and he suspects the high voltage from the charging system is the cause...... Still waiting to hear if the +30 is a transient reading - or continuous.......

[ray wilson]

can you tell me how to wire amp gauges to a 1957 morris minor with n /earth thank you ray

[bmcecosse]

You need to be extremely careful to insulate the ammeter wires very very carefully - because they are unfused and heavy duty cable, so quite capable of starting a fire if they short out...... I suggest disconnect the battery before doing this - remove the brown wire from the starter solenoid - extend it to the ammeter and then run a cable from the other terminal on the ammeter back to the solenoid. Simples! If the ammeter reads +ve with the lights switched on, swop over the wires on the two terminals. Job done.