Waynebaby Posted April 11, 2018 Report Share Posted April 11, 2018 Hi All, I've always considered auto-electrics to be some form of black magic, but this weekend I realised it was Voodoo, when my battery turned zombie. The car started perfectly on it's hi-torque starter on Sunday morning before I took it for a quick drive of 15 minutes, after which I parked up on the drive. An hour later I went to start it and was rewarded with silence when I turned the key, punctuated with intermittent clicking from the solenoid. The first thing I checked was the battery, which was showing ~13V across the terminals, but to be certain I hooked up the trickle charger and this showed "full" after about 10 minutes. Not the battery then. Next I checked all the earths and the continuity looked good. Not wanting to believe it might be the starter, I decided the problem was the solenoid and duly ordered a new one. Needless to say the new solenoid didn't fix it. I was resigned to having to get the hi-torque starter off when I decided to test the old Lucas starter motor using jump leads directly from the battery - nothing doing. Now, I knew the old starter motor was good when I put it away and so I re-checked the battery. It was still showing ~13V and was still happily taking a charge, but I was starting to have my suspicions. A quick trip for a new battery and normal starting service was resumed. I can't figure out the old battery, which seems to have turned into a galvanic version of the living dead over the course of an hour on Sunday morning. To all intents and purposes it looks alive, but in reality it can hardly produce enough power to properly energise the starter solenoid, let alone turn the starter motor. All my previous batteries have either faded away slowly over weeks or died quickly and completely overnight. Has anybody else had a battery turn zombie? Is there another test I could have done with a multi-meter which would have revealed the problem sooner? Wayne Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 11, 2018 Report Share Posted April 11, 2018 The problem is you can't test a batteries condition by just measuring it's voltage. You have to place a load on the battery and then measure the voltage. All batteries have an internal resistance. When new this will be very small. As the battery ages this will increase and reduce the capacity of the battery. In other words the internal fault only becomes apparent when you try to draw a lot of power out of the battery. A good test is on a charged battery is to put the headlights on and then measure the voltage. It should around 12.5volts and after a couple of minutes will drop to around 12volts. If it is around 9volts then you could have a problem, Dave Link to comment Share on other sites More sharing options...
Waynebaby Posted April 11, 2018 Author Report Share Posted April 11, 2018 Just goes to show that you can learn something new every day (especially when looking at this forum!) Dave, Thanks for that advice. I'll know what to do next time. Regards Wayne 1 Link to comment Share on other sites More sharing options...
Blitz Posted April 11, 2018 Report Share Posted April 11, 2018 Interesting post. Think I would have assumed the same ie battery fine. Will try and remember your Zombi story. Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 11, 2018 Report Share Posted April 11, 2018 Had batteries die just when you dont want them to Its really best when a car drives in for a service and wont drive out, takes some explaining to a customer Zombies and gremlins at work. Pete Link to comment Share on other sites More sharing options...
Andrew Posted April 12, 2018 Report Share Posted April 12, 2018 Guys An old trick i was shown to test a battery. get an assistant to hold the ignition key in the start position. Whilst he or she is doing this look in the top of the battery (If not a sealed type) see if there are bubbles in the electrolyte (Acid). if there are that cell is dead as the other cells are trying to make up for that one dead cell. For those of you who don't know a 12 volt battery is made up of 6 times 2 volt cells. A wet battery will only produce 2 volts per cell, it is purely that way with physics as a chemical reaction. The power of the battery is in the acid and water mix which is called electrolyte. not in the lead plates. Regards Andrew Link to comment Share on other sites More sharing options...
JohnD Posted April 12, 2018 Report Share Posted April 12, 2018 "look in the top of the battery" That's with the filler caps off - and so with nothing between strong sulfuric acid and your eye. NOT recommended! Or if you must, with goggles or a visor, or a mirror and torch, although what appears to be air above the acid is an explosive mixture of oxygen and hydrogen, electrolysed from the water. Dont mess with batteries! John Link to comment Share on other sites More sharing options...
dougbgt6 Posted April 12, 2018 Report Share Posted April 12, 2018 Andrew, Don't want to be picky, but it's 2.1 volts per cell . You can revive a battery by reverse charging it, it won't last long thereafter but, there is a short improvement. My son-in-law accidentally reversed charged my nearly new battery, took 6 hours on full beam to flatten it! Doug Link to comment Share on other sites More sharing options...
Andrew Posted April 12, 2018 Report Share Posted April 12, 2018 John D of course use goggles that is just common sense. It is not only sufficient acid it is a mixture of 10% sulfuric acid and 90% water, and that is called electrolyte. Doug it is actually 2.45 per cell when on charge as the overcharge factor is needed. This will then fall to 2.10. This should be across al cells as wet batteries Need what is known as a equisation charge. You cannot revive an battery at the end of its life no matter what claims are made. Active material falls of the lead plates ever time a charge is applied. This material will fall to the bottom of the battery into what is know as the mud space. This. Will then short across the negative and positive plates resulting in a dead battery end of story regards Andrew Link to comment Share on other sites More sharing options...
dougbgt6 Posted April 12, 2018 Report Share Posted April 12, 2018 Andrew, What is the"overcharge factor"? What is the "equisation charge"? What is the "mud space"? I can find not internet reference. And, I'm sorry but I've seen my Uncle revive a battery by reverse charging it. "Knocks the crude of the plates" was his explaination. Doug Link to comment Share on other sites More sharing options...
Mark B Posted April 13, 2018 Report Share Posted April 13, 2018 I bought a Ctech battery charger a couple of years ago and have recovered a couple of batteries that appeared dead and that I would have normally disposed of. My old start & charge, charger confirmed they were unchargeable, but the Ctech was able to bring them back to life, also gives you an indication of condition. Makes me wonder how many batteries I have premeturely retired in the past. Batteries do wear out eventually and not a lot you can do. Biggest killer in my experience is not enough use, so now I periodically recharge as a matter of course. Mark Link to comment Share on other sites More sharing options...
dougbgt6 Posted April 13, 2018 Report Share Posted April 13, 2018 Mark, Yes, some battery chargers won't charge a stone dead flat battery. I have one of those and another that will! Doug Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 13, 2018 Report Share Posted April 13, 2018 2 hours ago, dougbgt6 said: Mark, Yes, some battery chargers won't charge a stone dead flat battery. I have one of those and another that will! Doug Doug it may be due to the waveform left after rectification because what you get out of a charger is not pure DC. If there is any charge still in the battery this will smooth the waveform to produce true DC and should improve the charge. A flat battery will not do this. The waveform can vary with the design of the charger. e.g. full wave or half wave rectification. A 2000 MFD 50VDC capacitor across the charger leads may help. Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 13, 2018 Report Share Posted April 13, 2018 Wave Form ................dont wave at Doug he's just been appointed as AO ,,feel sorry instead Pete Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 13, 2018 Report Share Posted April 13, 2018 7 minutes ago, Pete Lewis said: Wave Form ................dont wave at Doug he's just been appointed as AO ,,feel sorry instead Pete As an ex AO, well done Doug. I am sure Pete will tell you all the info on being an AO. We are looking for a new AO for Newbury Area as Lloyd our present is on the move. Dave Link to comment Share on other sites More sharing options...
dougbgt6 Posted April 13, 2018 Report Share Posted April 13, 2018 Thanks Dave, our beloved leader Mark is off to Warwickshire, he and the others have done me up like a kipper! To show willing I'm off to the AGM on Sunday, picking Pete up on the way. Doug 1 Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 13, 2018 Report Share Posted April 13, 2018 Doug, Make sure you remind Pete to take some Gaffer Tape to the AGM! Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 13, 2018 Report Share Posted April 13, 2018 it there message in here ???? pete Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 13, 2018 Report Share Posted April 13, 2018 Pete, if you remember we needed it at one of the AO meetings at Stafford. Dave Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 13, 2018 Report Share Posted April 13, 2018 Was that when they cocked up the asscociate rule nightmare Being old the hard drives wonky well more wonky !! Pete Link to comment Share on other sites More sharing options...
dave.vitesse Posted April 14, 2018 Report Share Posted April 14, 2018 Yes! Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 14, 2018 Report Share Posted April 14, 2018 that was one of the better ideas to loose members not gain any ........ very discombobulated idea and still remains so compared to all other clubs Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted April 14, 2018 Report Share Posted April 14, 2018 Never mind Pete, were all gonna be dead by tea time, so it doesn't really matter! My brother's off to his daughter's wedding in Cyprus, 5 miles from RAF Akrotiri. His girlfriend is, a little anxious?!! Doug Link to comment Share on other sites More sharing options...
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