My girlfriend has a 96 Integra LS, she called me this morning to tell me her car wouldnt start. So she took it in (I would have looked at it but she lives 1hr away)
and was told that the alternator is over charging the battery, which will eventually cause the battery to explode. Is this a common problem? I have never heard of this and have been working on cars for a good while.
lastly, the tech told her it would cost $460 to replace the battery and alternator, which seems extremely high to me.

any tips or advice? TIA

 

Unless overcharging killed the battery the car should have started. I do not recall if the voltage regulator is built-in with the alternator if not then start by replacing the voltage regulator. She should take it to the dealer or a Honda-Acura specialist shop.

 

Get a voltmeter and measure the charging voltage at the battery. It should be no higher than 14.5 volts under any circumstances (lights and a/c off, cooling fans off, 3-5K rpm). Battery explosions can occur from overcharging, but it is more common during cranking. Voltage regulator is built into the alternator -- rebuilt units go for about $80, same for a new battery, so based on the quote you have, I think you're getting hosed...

 

overchargeing is usually found on older setups without belt tensioners. What happens when a belt is too tight is that a more of a "drag" or strain(sp.) on the alternator bearings as well as the brushes. As far as there being a voltage regulator i think there would be something like this if not just a simple set of resistors. You would hear a whinning kinda noise from the bearings in the alternator if it was overtight. This can come from a pisspoor tune up at a franchise type place or any garage really that doesnt use a belt tensioner or something like that.

Batteries usually always explode in a discharged situation where there is one or more cells gone bad resulting in a build up of hydrogen gas. This gas has explosive properties of course and when a spark, high resistance, or short to ground occurs this occasoionally ignites fumes around the battery. However most batts. are designed to prevent this from happening with sealed and safety cases.

hope this helps.

but anyhow, sounds like she is being taken for a ride. Both could be ok. But a good slow charge on the battery overnight and check the alternator for good working condition.

 

if im not mistaken the alternator only keeps the battery at the correct amperage, it doesn't really charge it. so if it is over doing it then you have a toasted voltage regulator!
basically its thinking that the battery is running low so it engages the alternator to boost it up!
get it rebuilt! the alternator is probably fine just the regulator is pooched.
also get a load check done on the battery, the battery still may be good!
this should save you some casH!