[tbil]

Any thoughts on the following problem ecountered on my way into the office today in my 75 1.8 daily driver?

The volt meter peged at 15/16 during normal driving with no lights etc. running. After maybe five minutes it returned to it's normal 12/13 reading and then later pegged again without anything electrical turned on or break pedal pushed. Is likely to be the voltage regulator going out or is it diodes in the alternator. Can the alternator be replaced without dropping the engine?

Thanks for your thoughts!