

| Subject: | Re: battery questions |
| From: | Aristotle Sagan |
| Date: | Wed, 31 Mar 2004 17:12:26 -0800 |
Gerry strips attachments... What's up? tim (not opening any of your attachments) in san jose ----- Original Message ----- From: "Sam Walters" <sam.cooks@VERIZON.NET> To: <vanagon@GERRY.VANAGON.COM> Sent: Wednesday, March 31, 2004 5:01 PM Subject: Re: battery questions > Attached are a few text files that I cut out of posts to the list about > the same sort of problem. They might help. > > Sam > > -- > Sam Walters > Baltimore, MD > > 89 Syncro GL > 85 Westy Weekender > 84 Vanagon, original owner, soon to be retired, just too many problems > > All incoming and outgoing email scanned by > automatically updated copy of Norton AntiVirus. > > ---------------------------------------------------------------------------- ---- > Check for source of battery drain > > sstones@DIRECT.COM > > Well... > One way to start into tracking it down would be to pull each fuse out and > check the amperage across the clips with a multi-meter. Compare the ones > that have significant amperage to the wiring diagram to try to guess for > likely suspects, and narrow it down from there seeing what things do and > don't have a positive voltage beyond their switches or relays. > > hradek@YAHOO.COM > > Steve, > make it simple. Pull the fuse to the > radio,clock and lighter and see if the problem goes > away without that fuse. This is the only circuit > that is always on? gary > > bearsvw2000@YAHOO.COM > > Take the fuse out to the clock, loosen the positive > terminal on the battery, wait till dark or darken the > battery area. Take the positive terminal and check for > a spark, getting that, start pulling the circuit's > fuses untill you loose the spark, this will be the > circuit to check for a ground. This can also be done > with a meter in line with the battery to check for a > amp drop when the area of the problem is isolated. Phil ---------------------------------------------------------------------------- ---- > Doktor Tim's Battery Alternator Check > > > To proof your battery and charging system follow these steps and skip none > if you don't want to waste money on what it isn't. > > 1. Verify both ends of both batt cables are clean and tight. Same for the > ground strap at the front tranny mount. > > 2. Verify the battery top and case is clean and dry. > > 3. Verify battery is fully charged. You need an accurate VOM for this and > all the following. > > 4. Turn the key to on then turn on the bright headlights and blowers and > watch as the volts drop to about 12.3v. Then turn everything off and watch > the volts rebound to 12.6+ within a minute or two. If it drops lower than > 12.3 within a minute or so, the battery is weak. If it will not rebound to > at least 12.6 it is also weak. If the battery passes this test then you can > use the bucks you would have wasted on replacing a good battery to go to > eBay and buy a quality $200 multimeter for the price of a good extra duty > group 41 battery. > > 5. Only now are you ready for a test of the alternator. At idle, place one > lead on the batt + and the other on the alt output. If you read more than > 1/2 volt you have a problem with resistance in the wiring to the battery. > Recheck the big lug connections at the starter for clean and tight. If you > have less than 1/2volt drop, hook up the multimeter to batt + and - while > idling. Should see 13.8 or so with no other loads. Turn on the brights and > blowers. At idle should not drop below 13.3v. Rev to 2000+ and with the > loads should not be less than 13.5v. Lower numbers say replace the weak > alternator, but before you do, replace the indicator bulb. An old bulb can > have resistance that will not keep the alternator excited. > > Over 95% of the time these steps will identify your problem and you won't > waste a cent on good parts. The 5% is related to some very occasional > issues of strange battery behavior. Battery continually tests good but let > it sit for a few days and low charge. I have seen these strange batteries a > few times, and several that were new and had these strange faults from the > get go. If I have truly verified all steps as above and still have issues, > then I will disconnect the battery, put a full charge on it, load test and > watch rebound come back good, then let it rest for several days while > monitoring. If it drops more than a 1/2 volt in a week, then the battery is > weak. A dirty battery top will always fail this test from losses due to > cross cell flow through the dirt/acid conductor all over the case. > > Easy squeezy test for cross cell flow. Connect multimeter + to batt +. > Touch multimeter - to various places around the battery top. If you see a > few tenths of a volt, not bad. If you see more than 1 volt, the case is not > clean. I have many times seen 8 to 12 volts cross cell flow on filthy > batteries. This sucks the life out of the battery, alternator and starter > and the continuous loss of amps means everybody must work under much higher > stress. You get no work from those lost amps and you must pay extra in lost > life of components to replace them. > > After all these items have been verified and you still have a draw issue, > then begin looking for other items drawing amps in excess. ---------------------------------------------------------------------------- ---- > Checking alternator and for short discharging battery > > Take care to be safe while doing any of these suggestions! > Simple ways to check things out without : > Start engine and remove vehicle's positive lead from battery. DON'T short to > frame or let lead touch frame! > > If it continues to run alternator is working. Increase draw by turning on > additional electrical units, headlights on high, a/c blower on high, > continue with other things, if it kills the engine. Voltage regulator is not > working properly. > > If you believe you have a short in a system somewhere. Turn everything > (lights, radio, etc) off first. In the dark unplug your fuses and replace > them while watching for any sparks (do this with the engine running, then > with it off but the key on and last with key off). > > Radio's, clock's and such, usually only give a little spark, shorts that are > draining your battery should be brighter. However don't put it past them to > be the problem. If you don't find any other sparks, leave their fuse out and > see if the battery still dies. > > The same thing with the alternator, with the engine OFF! Removing or > replacing the battery terminal on the alternator, should NOT spark. > > Last year I worked on a (16 year old, know-it-all) kids pickup. After HE > installed a new starter, the truck began to stall but would start right back > up. This would happen when he'd make sharp turns, hit large bumps or take > off fast. So he decided the truck needed a new battery. I offered to check > it out but he (bosses live-in's boy) knew that it just needed a new battery, > fine...The problem continued the next day but this time it left him stranded > on the road. He had it towed home, where it sat for a few days (he was the > only one smart enough to work on it). > > My boss grew tired of dropping him off at school and told me to check it > out, but the kid would do all the repairs himself. > > Lifting the hood, I saw the bulging NEW ($102.00 only the best for his > truck) frozen(mid November) battery. I pulled the positive lead (battery out > of circuit) off the battery and was connecting the cables. They sparked as > if I was welding. Yanking them off. I traced the positive wire down and > under the manifold but could not see it. So sliding my hand along the wire I > felt it welded to the manifold. > > Don't be afraid to ask, take the time to do it right and save yourself a lot > of trouble later. > > So, if you can't check out your alternator take it to someone who can. > Paul > > oliver8@TDS.NET
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