The battery in my 240 GLE seems to keep leaking from the top. Two weeks ago I removed the battery, cleaned up the terminals, battery and tray with soda, and reconnected. Tonight I see that the tray is full of battery acid and the battery top and sides are wet.
I checked the voltage non-running and got 12.5 volts on the battery. I then checked at 700 rpm and again at 1500 rpm, and got 14.3 volts. Thus, the alternator is working properly and the regulator is allowing the correct charge to come through.
How do I check to see if the regulator shuts off the charge when the battery is fully up, or is this not the way things work?
Do I have a bad regulator, or do I have a bad battery? Any other things to check?
Thanks
JD

14.3 is not outlandish. but i think the mean for a bosch is more like 13.6 - 13.8 v
--
mike, 1988 Volvo 240DL 114k , , previous 79 & 81 Volvo 244s

Certainly does sound like an over-charge condition. The voltage regulator works by limiting the current in the field winding of the car when the voltage is about 14.3 as you see. With no current in the field winding, there is no magnetic field to cause a voltage to be generated in the 3 phase windings.

I would suggest that one of the cells is shorted, but then it would be unlikely to see 12.5 volts when not running. How old is your battery?

I would hook up a volt-meter and check the voltag while driving. I had a faulty regulator on one car and the voltage went up to about 17 volts at higher rpm. Maybe you just didn't rev the engine high enough to confirm a faulty regulator. See what happens at 2,500 to 3,000 rpm.

Good Luck,
Dan

I hooked up a voltmeter and ran into town today while watching the volt meter. It stays steady at 14.3 Volts the whole time, never wavering more than a point or two (14 to 14.3). Does this indicate a bad battery. THis would indicate to me the regulator is working, although I would have thought that once the batter was fully charged the voltage output would drop slightly. As you can tell I am not too knowledgable about how the regulator works. As the battery continues to seep out the top, does this indicate a bad battery?
JD

Mine drops a bit as it gets warm, especially right under the exhaust manifold.

Dan,

Just curious. Did you have that shorted regulator on a Bosch? So far I've not heard of that here in Volvo-land. And thankfully so, as there're few things worse than the messes of overcharged batteries.

On the other hand, like you said, I've seen batteries with such bad accumulation of sulphated crap under the plates that cells short intermittently, especially under heavy charge, yet, due to the intermittent nature of the short, can read normal 6-cell voltage when the meter's in place.

Hard to find, even with a voltmeter, as the internal resistance of the battery including the "short" is overcome by the alternator's 60+ amp capability. Leads someone like me to go to the trouble of temporarily installing ammeters (!) although admittedly that was a red herring.

Well, if I saw the voltage creeping up to 17, that would be another story, along with the accelerated demise of headlamps, etc.
--
Art Benstein near Baltimore

The faulty regulator was on an '81 240 that my daughter had for a while. I can't swear that the voltage was all the way up to 17 Volts but not far from it. I don't know for sure the brand of alternator, but I think it was a Bosch. Not an extenal regulator - regulator/brush unit mounted to the back of the alternator.

This was one of my earlier Volvo repairs, before I found the brickboard. That car suffered a sudden death on the highway one evening, engine sized(?). The car belonged to the ex-wife and I never found out the actual cause. I have always been suspicious as the disaster occurred a couple of days after an oil change.

I replaced that car with a real clean '82 240. Two weeks later I got the opportunity to learn how to repair a rear quarter panel. That car had a rusty fuel tank. I figured that out pretty quickly after a couple of fuel pump replacements. About this time is when I decided that I needed to get back into the personal car repair business. Then came the '87 740 which was to be a three year car, long enough to get her out of college and into the working world. That was five years ago and the car is still running strong, even with the infamous ZF transmission, and she is still in school. It is Law School now and I think she would prefer to be a professional student, but I can't imagine any other schools for her to attend, so I guess now she will have to get a job. Only need eight more months on that '87. Ha Ha. Maybe if I get all the quirks worked out of the '89 760 TI I'll let her have it some day. I am always keeping my eyes open for other Volvo opportunites.

Dan

P.S. My guess for the photo contest is part of an abs pump.

Dan;
I am not sure of the age of the battery as I have just had possesion of this litle jewel of a car for only a month or so. Its the second 240 I have had, and this one, even with a few minor glitches, is just great.
Tomorrow, despite the snow we are receiving tonight, I will hook up the voltmeter and take the car for a spin (no pun intended) and report back.
JD