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MG MGB Technical - New Batteries

Hi,

This is a bit of a stupid question but here goes...

I have just had to buy two new 6v batteries for the B. I could only get 'dry' batteries, I was given the acid pack and have also bought some distilled water.

Question is how much acid and distilled water do I put in each cell, once filled can I just put the batteries in the car?

Thanks for your help

David
David R

David, I believe it is 35% acid to 65% water but I have only bought battery acid that is pre-mixed ready tp pour into the battery. I didn't know they sold it 100% acid. Maybe it's different in the Old Dart.

Tony
Tony Oliver

http://www.batterystuff.com/tutorial_battery.html
useful stuff here. You must be very careful mixing the acid. Water to acid results in spitting concentrated acid so add acid to water. I guess these are dry charged batteries(you can charge a lead acid then remove the eloctolyte and it stays charged) so making the electrolyte up to the correct SG is vital, I think thats where the number above comes from and there is some info on the link above. As for volume, you need to make up enough to cover the plates if no data is provided then I would make up 50% of the volume as derived from measuring the outside of the case and fine tune it from there if it was me. Once again, careful around that H2SO4. Even dry charged cells will benifit from a trickle charge after you activate them. Let us know how it goes, I have only ever read about this technique never had to put it into practice.
Stan Best

Frankly I'd be demanding that information of the retailer. I think it amazing, in this day and age of litigation, that anyone would package and sell that combination without very full and clear instructions printed on the packaging.

Regards
Roger
Roger T

As I recall, but it was many years ago, I got a separate acid pack for each cell which you just tipped all in, one to a cell, and topped up with distilled water. But I see now the MGOC sells them with a single electrolyte bottle of the correct specific gravity so you just fill each cell from that up to the tops of the separators. You need to be sure which type you have.
Paul Hunt

Thanks for the replies.

I have two packs of acid that are the same as the ones pictured on the MGOC website

http://www.mgocspares.co.uk/acatalog/MGOC_Spares_BATTERY_119.html#topanch

So I assume 1 bottle per battery. Split the bottle across the 3 cells and then top up with distilled water to above the separtors?

Just a case of measuring the acid out to get a equal amount in each cell...

David
David R

Certainly the description "battery acid" does imply it is the correct SG to just pour in, slowly. 1 Kg seems a suspiciuosly round number and if the SG is correct you should not add any distiled water. As it is the MGOC I would ring and get clarification.
Stan Best

David, if you have, or can get hold of, a hydrometer for testing batteries you could test the bottles first to see if the specific gravity is correct for a pre-mixed solution. 100% acid is pretty dangerous stuff and my experience over here is that you can't get it.

Apparently it can be used to make bombs! Over here it is to be reported if anyone tries to buy it. I found that out when setting up a copper plating kit. In the end I was able to get "battery acid" which is 35%/65%.

Tony
Tony Oliver

One of those funny things that sticks with you, but I remeber this from highschool chem.

DO WHAT YOU OTTER, AD ACID TO WATER.

Just bought a motorcycle battery here in the states and it also came "Dry". Acid with it was premixed.
Bruce-C

If the packs you have *are* the same as the MGOC sell then as I say the accessories catalogue states that they contain electroltye of the correct specific gravity i.e. it is already diluted with distilled water, so you simply fill each cell with what's in those bottles. They should have supplied enough which means their won't be any room for additional distilled water, and in fact you will probably have a little electrolyte left over. If you *bought* them from the MGOC, then if you are in any doubt it would be far better to phone them up and ask. I would also expect clear instructions on or with the bottles, this isn't something to be mucking about with and doing the wrong thing.
Paul Hunt

Hi all...

Although I didn't buy the batteries from the MGOC I have given them a call. They said that the acid will be mixed and one bottle should be used in each cell.

I was only given two bottles with the batteries - time to phone the place I bought them from...!

Thanks for all your help, have added the batterystuff.com link to my bookmarks

David
David R

This thread was discussed between 08/06/2008 and 09/06/2008

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