Problem with battery after replacing cooper-S engine

[mrwarby87]

Hi guys,

I had a new engine fitted to my 2002 cooper-S a few week ago, since then the battery hasn't been charging... all the wires going into the alternator look fine, don't think anything can be draining the battery as the charging circuit was fine for the 9 months before I put a replacement engine in, the battery is brand new so should hold charge, the alternator was fine before so it would seem unlikely it would pack in the day after my engine was fitted?

My main question is, which I can't seem to get a definite answer to is... when I put the ignition on, the battery warning light doesn't come on, and never comes on when the battery is dying etc. So i'm guessing the bulb has gone, but does anyone know for definite whether a blown bulb could stop the charging circuit or should it just bypass it...? Or any other suggestions?! Also i've checked all the fuses!

Thanks!
Matthew

[marque]

Hi

dont know if you have tried this put a multi meter across your battery terminals and set it to 20 volts dc (more than 12volts required) start the car and measure the battery voltage normaly around the 12 volt mark if you turn on the lights the voltage should go up a volt or two if it does not the battery is not charging now if thats the case have a good look at your engine earth points there are a few if one is not conected or has been broken which you may not be able to see if it has a heat shrink sleave on it normaly the one that goes from the engine mount on the drives side to the body gets forgoton and i think there is one on the gear box a qucik way to see if you have an earth problem is get a jump lead for starting cars connect it to the top of the big engine mount on your drivers side (uk car) then connect it to a nice clean solid lump of body work Paint free or a big ish bolt not back to the engine if you have long enough leads conect the two together take it stright from the mount to the battery - (black) (negative)
start the car after making shore the leads are not touching anything they should not be and then see if the battery is charging buy using your mulitmeter on it again with out lights 12 volts ish and then with lights the volts should go up when you turn the lights on.
if this fixes it you may find it will sort the warning light out as well as it may be looking for and earth return
then its just a case of finding the earth thats broken or missing or making shore its clean good contact rust and paint free
i hope this helps costs nothing just abit of time to check out i hope it solves it good luck and let me know how you get on i will have a think as well and i am shore some one else here will have a few more idea to help you

mark
mark

[mrwarby87]

Thanks for that advice! Makes sense, will definitely try that tomorrow and let you know how I get on!

Cheers,
Matthew

[Dan1978]

Quote: Originally Posted by mrwarby87 (original)

Hi guys,

I had a new engine fitted to my 2002 cooper-S a few week ago, since then the battery hasn't been charging... all the wires going into the alternator look fine, don't think anything can be draining the battery as the charging circuit was fine for the 9 months before I put a replacement engine in, the battery is brand new so should hold charge, the alternator was fine before so it would seem unlikely it would pack in the day after my engine was fitted?

My main question is, which I can't seem to get a definite answer to is... when I put the ignition on, the battery warning light doesn't come on, and never comes on when the battery is dying etc. So i'm guessing the bulb has gone, but does anyone know for definite whether a blown bulb could stop the charging circuit or should it just bypass it...? Or any other suggestions?! Also i've checked all the fuses!

Thanks!
Matthew

Out of interest, how much was it to replace the engine and get it fitted?