

| Subject: | Re: Cause of the white corrosion deposit around a battery? |
| From: | Doug Alcock |
| Date: | Wed, 17 Mar 2010 12:09:36 -0400 |
So are you ever gonna live that one down............ Cheers, Doug On Wed, Mar 17, 2010 at 10:27 AM, Don Hanson <dhanson928@gmail.com> wrote: > Thanks everyone. > > Good explaination, Mr. Dave. I've seen those little felt rings. Never > realized what they were on the posts for though. and Ry, good tip about > cleaning up with Soda Water. I've used baking soda in solution before, but > some Perrier would be ever so much more 'classy' (and easier) > I just found out about 'high temps' around batteries. My wife's Ford > Diesel (two big starting batteries (in series?) just needed new batteries, > which she brought home (in that Subaru) from Les Schwabb and installed in > her truck herself. She was in a big hurry to go to Idaho to get a horse > so I was helping her re-connect the brand new batteries to get away at > dawn. She had the terminals on the right hand battery, but the driver's > side was still un-connected. I double-checked to see that she'd got the > passenger side batt. in place correctly and then looked at the driver's > side, which was set in there the same way. "Great", I thought, "She got it > right" and in the dawn "light" I dropped the cables onto the posts...which > gave out a huge flashing arc! The one side was required to be installed in > 'mirror image' of the other, it turns out...the + post of the battery that > I > 'helpfully' tried to instal backwards was turned into a puddle of melted > slag! $100+ mistake. note to self: Coffee and a headlamp *required* when > doing pre-dawn auto mechanic's stuff. > Don Hanson > On Wed, Mar 17, 2010 at 6:54 AM, Dave Mcneely <mcneely4@cox.net> wrote: > > > to more completely answer the question, I believe the deposit is metal > > sulfate produced when sulfate condensate from the battery comes in > contact > > with metal. Either grease or oil will prevent it. If you want to get > > fancy, most battery vendors sell little felt circles impregnated with a > > substance that blocks the corrosion from developing. Just slip the disc > > over the post and tighten down the clamp. They come in red for the > positive > > post, green for the negative, and they work. If you do use oil or > grease, > > remember to tighten the clamp down before greasing the post, of course. > > There is also a special material sold in a squirt can. It coats the > > terminals with a purplish plastic like substance that also blocks > condensate > > and air from the terminals but in no way prevents clamp removal. > > > > So far as only the positive post corroding, I believe the sulfate can > > condense on any surfaces in the vicinity of the battery. In extreme > cases, > > the entire support system for the battery will fail. If the corrosion > were > > from oxygen rather than sulfate, then on steel parts, the substance > would > > be rust red. Now, eventually such parts do rust, if the sulfate > corrosion > > doesn't get them first. > > > > In the simple case, perhaps the lead post itself is corroded with a > simple > > lead oxide, but when the corrosion is over other parts, it is metal > sulfate. > > > > DMc > > > > ---- Tom Hargrave <thargrav@HIWAAY.NET> wrote: > > > It's corrosion and should only be on the positive terminal. > > > > > > Sometimes you have a leaky seal around a post but this is rare these > > days. > > > More often the corrosion is because the + side of the battery attracts > > > oxygen ions from the air and the oxygen interacts with the metal, > causing > > > the corrosion. > > > > > > There are a lot of "fixes" you can buy but the best one is to put a > drop > > of > > > oil on the terminal every time you check your oil. The oil will spread > > out > > > into a thin film & will protect the terminal from corrosion. > > > > > > Some people put grease on the terminals. Grease will also work but you > > need > > > to make sure to cover the entire terminal, even the bottom edge of the > > > clamp. If you don't then any exposed metal will corrode. > > > > > > Tom > > > www.kegkits.com > > > > > > > > > -----Original Message----- > > > From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On > Behalf > > Of > > > Don Hanson > > > Sent: Wednesday, March 17, 2010 12:04 AM > > > To: vanagon@GERRY.VANAGON.COM > > > Subject: Cause of the white corrosion deposit around a battery? > > > > > > What makes the powdery white or gray deposits on some of the metal > > parts > > > around the van batteries? Actually my Vanagon stays pretty free of the > > > deposit, but we inherited a 2.5 Subaru Forester that gets it bad. We > > stored > > > it down in Californa during the summer and use it as a vacation car. We > > > opened it, around Xmas time to find the battery(disconnected but fully > > > charged) was covered with a whitish powdery deposits, heaviest on the > > > hold-down ring and the clamps, but also under the batt on the tray. I > > > bought another new battery...and cleaned everything up with baking > soda, > > > like a good little car guy before installing that one... > > > > > > We brought it back to the NW...(shhhh...I'm hoping to finesse it (the > > > motor) from my wife, eventually..for use in a ....) and I just noticed > > that > > > the hold-down clamps and the retaining ring is again almost pure white > > with > > > a fine powdery substance...Both my Ford Diesel trucks do the same > thing, > > but > > > to a lesser degree. > > > > > > What the heck is this stuff and how do you prevent it forming? > > > > > > Don Hanson > > > -- http://www.dougalcock.com
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