car battery - really necessary to use distilled water??

free4440273

hi, this has been bugging me for a number of months (yrs!): I have a very old petrol car (N reg) and I always top up the battery elements with distilled (ironing) water. Is this really necessary, or it it safe to start using tap water? thanks all:)

Crabman

There are minerals present in tap (or mineralised) water which can cause corrosive damage to the cells inside the battery, this is why distilled water is recommended.

steveo3002

ironing water is distilled...i doubt its gona make a huge differance if you use a little tap water instead

free4440273

(sorry, i have used the incorrect terminology in my op - edited it now. thanks, so probably best to carry on using bought distilled water. It's not the cost (just a few pence!), but sometimes you don't have any lying around. any other replies always grateful:)

oldagetraveller

As a last resort in the past I've added a little tap water very very occasionally with no apparent detriment. I lived in a very soft water area then (Manchester from the Lake District). I would think twice about it now though living in a "hardish" water area

goldspanners

im my short existance on this planet ive topped up a shed load of lead acid batteries,thousands infact. in scotland the tap water is soft,no lime so its absoloutley fine to use this water,ive used it topping up batteries for years and its been no problem,its seen the battery beyond its expected lifetime so no problems.
however using tap water in say london might be a bit differnt,maybe filter it get the lime out of it and then use it.
it really isnt an issue for soft water areas.

why are you topping your battery up so much anyway nowadays? most batteries are sealed now anyway. with the exception of traction batteries of course.

free4440273

^thanks. Well, I am topping it up periodically (not very often, maybe every four/five months) when the electrolytes are showing. My Peugeot manual (i have an old petrol N reg car) states to 'cover up' the electrolytes with water if they are bare (if that makes sense). It's one of those batteries which has six or so little 'screws' which you can unturn with a penny coin:)

Am I doing the correct thing??

oldagetraveller

I know what you mean, small round plastic plugs on top, removable using a coin. I've always removed these to check level is above plates on a "maintenance free" battery and the levels do drop over time. Maybe the manufacturer relies people not doing this check and the battery then packs up very soon after the warranty has run out!
If the level(s) is/are dropping all the time though and at a high rate and topping up is constantly needed there's something not right.Four to five months sounds about right from past experience.
I know Halfords "maintenance free" batteries have the plugs.

free4440273

^indeed. yes, it is about four/five months - sometimes even longer.

sassy_one

You are perfectly okay using tap water in a car battery that can be topped one, and if you really wanted to you could boil some tap water in a kettle

ariba10

sassy-one wrote: »

You are perfectly okay using tap water in a car battery that can be topped one, and if you really wanted to you could boil some tap water in a kettle

How will boiling the water change the mineral content?