So i have bought a new external voltage regulator for my 120y and replaced the brushes in my alternator

the problem i am having is that when the ignition is turned on the charge light does not turn on

then when you start the car the charge light turns on a will keep getting brighter as the rpm increase my multimeter shows close to 16volts

and when i connect the external regulator the engine seems to sound loaded up and when you disconnect it the rpm goes up abit

this makes me think its a voltage regulator problem but its brand new

any ideas?

Thanks