I received some good help recently with a charge light problem. It ended up being a faulty diode trio in a rebuilt alternator causing the dash idiot lights to glow. Now today my daughters 240 boiled all the water out of the battery. It took a full gallon of water from my dehumidifier to fill the cells back up. Car literally had smoke coming from the caps when she got home and it stopped running. I thank GOD I explained to her about battery gassing and the possibility of explosion! The car restarted after refilling the battery and I took it directly to the NAPA store for a charging system test. Both Battery and alternator tested good, however I know the buldge in the side of the Battery can only mean it will need replacing soon. Am I missing something here??? Grounds are solid, alternator output at 13.8 at idle no additional issues that would indicate a short... Any suggestions appreciated!!!
Thanks,
Frank

Could be the battery has a shorted cell, but one shorted so bad as to boil the others is rare.

It is not a short on the small red wire. If that was shorted your dash warning lights would all come on and you'd have no charging at all.

Best chance the alternator is not Bosch, a poor rebuilt, or the regulator is dead shorted once it warms up. You definitely need to confront the supplier of your current alternator once you've confirmed your battery is not boiling with 13.8V across it.

Since this is the second rebuillt alternator in a month, and after recharging the battery completely and having the voltage soar past 14.2, I agree the quality of the rebuilder is my main issue. I ordered a bosch regulator from a local bosch dealer. Hopefully, the rest of the unit will survive for alittle while. If not, I will be turning in an expensive shiny core to a quality rebuilder soon. Live and learn!
Frank

Good lord that's certainly unpleasant. Lucky the battery responded to a refill.

It sounds to me like possibly the small red wire is grounding out somewhere in the harness or under the car or next to the alternator on that foil hose?

If it were to ground out, the unit may try to charge excessively.

You said a rebuilt was just installed- have a close look at all the alternator connections, and make sure the red wire is intact next to and below/inboard of the alternator where the harness goes through the bracket behind the pulley. Also inspect the blue ground wire at this time- make sure the 8mm nut is tight on the alternator body, and the 12mm bolt to the engine block is good right below the alt bracket.

Good luck with it!
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Rob Bareiss, New London CT ::: 92 244-M47-207K ::: 90 745GL-M47-268K ::: 88 245DL-AW70-230K ::: 88 244 SOLD! 87 244 SOLD! Still looking for a bright red or black 244 with sunroof...

Sound to me like you just have a junky battery. I would err on the side of safty however go ahead and replace the battery espicaly if it has a bulge in the side.

Battery was a Volvo Factory unit dated 8/04, probably would have lasted longer if the voltage regulator was a factory unit...like it is now. The battery lasted 2 day's then a cell shorthed from all the heat and wouldn't hold better than 10 VDC.