Correct battery for bis

[Njkip]

Hi all, can anyone advise me what is the correct battery for my bis, I currently have a 063 fitted ( was in when I got car) it's 30ah crank....I think it's causing some starting problems, just doesn't seem to wiz it over fast enough, so won't start until I attach a booster battery...I've had the battery tested and it fine, so I was looking at 063 but with 45ah crank, any ideas guys.....thanks...👍

[andyzeetec]

I have a Bosch S3 077, bought one off ebay a while back. (I believe they are a special as the +/-poles are opposite ends to standard )

For info the BIS owners manual states.. Capacity  34Ah and 140A cold cranking power.

You sure the battery is good and fully charged, was it load tested, these drop testers not only check volts but apply a load to check for a faulty cell and short circuited cell. https://www.ebay.co.uk/itm/112509680843

Maybe check and clean electrical connections terminals on starter motor, worn brushes. Oilite bushes wear, check motor turns freely, but not excessive play

[ChrisRLewis]

EurocarParts and CarParts4Less are stating that the 077 battery is compatible with the bis. Carparts4Less price is £64.27 with coupon with free delivery.

[Njkip]

Hi guys, thanks for the info, yeah it was load tested and it was ok....I've replaced the battery terminals and done a proper job....soldered them on.  I've made a new earth lead and fitted that...you may have a point about the starter connections as sometimes when I turn the key there's nothing, if I fiddle with the wire on the solenoid it kicks into life..... it does seem to turn over slower than I would have thought, until I attach a jump battery that is...as I've said in previous posts the car has been stood for a long time before I bought it so maybe I just need to clean the connections on the starter end....It has had an electronic ignition fitted so don't know if that's anything to do with it not fireing up...do you know if it is possible or safe to put a bigger crank AH battery on, something like a 45AH as they do one in the 063 which does fit in the battery bay.....any thoughts? As always thanks for your input (s)

[Njkip]

Just looked at the 077 batteries, the CCA varies between 380 and 440 which is much more that what's on my 063 and more than the one that's recommended.....so if a get one of those with that amperage I'm assuming it'll not cause any damage ....I guess it must be ok if Andy is running with one....

[andyzeetec]

Found this..

Amperage ratings are just a maximum, so equipment will only draw as many amps as they need.

A larger battery with more ampere hours can store more energy, and a battery with a higher CCA rating can pump out more current faster when you start the car - the starter will draw as much as it can handle, though, the battery isn't "pushing" a flood down the pipe.

[Njkip]

Nice one Andy that's very helpful....I'll get a new battery and see where it goes from there....thanks again....👍👍