I HAVE A ROVER 418 DIESEL L REG WHEN ENGINE IS TICKING OVER FOR ABOUT 15 MINUTES THE BATTERY GETS VERY HOT CAUSING THE BATTERY TERMINALS TO SMOKE ANY IDEAS WHATS CAUSING THIS TO HAPPEN

JIM, September 2007

If it is only the terminals that are smoking it means that they are arcing. Clean them with some emery cloth or similar and then coat them in Vaseline (petroleum jelly) NOT grease or other lube.

If it is REALLY the battery itself that is getting hot get an auto electrician.

t, September 2007

sounds like the alternator is overcharging the battery, use a multimeter in volts dc and measure the batter voltage before you start the car. shouldn't be normaly 12.65 - 14 volts.

With the engine running the battery voltage should not be more than 14 volts if so then i'd say that the voltage regulator in the alternator needs replacing, depending on make of alternator the bosch ones just screw in, you may or may not have to take the alternator off to take the regulator off, depends on if you can get at it.

Some alternators require the whole alternator to be taken off and taken apart to fit the regulator.

jim (vw mechanic)., September 2007