Stop in for a cup of coffee
Something in the wires or connections from the bulkhead to the regulator that causing over 0.5 Volt drop.
So the regulator thinks its letting through just enough current for the alternator to be 14.2 - 14.4 V
Its only doing that because the regulator isn't seeing the 15 V.
Something in the wires or connections from the bulkhead to the regulator that causing over 0.5 Volt drop.
So the regulator thinks its letting through just enough current for the alternator to be 14.2 - 14.4 V