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Problem After Fitting New Bosch Alternator Bxn1231A


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I've already posted this in general maintenance but thought i'd post here as well for more exposure. as the title states im having a problem after fitting a brand new bosch alternator to my r33 gtst to replace the existing factory alternator. I did not have any problems with the battery or charging prior to this. I have the battery factory located in the boot and noticed after driving today that it was extremely hot to touch and liquid had started seeping out from it even though its one of those maintenance free batteries. Just before taking it for a drive I started it up to make sure everything was good and let it sit for a few hours then went to touch the alternator and it was still really hot. like it was still charging the battery or something. when fitting it I disconnected the battery as per usual and followed all the instructions, tensioned the belt correctly etc. I noticed on the factory alternator it had 2 cables screwed to it. a bigger one which goes to the battery and another little cable which screws to the alternator housing for grounding or something. but on the instructions with fitting the new one it only had the one big cable and plug connected. I'm thinking there is either something internally wrong with the alternator or that little cable wasn't meant to be fixed to it. anyone had any experience with these bosch alternators or has a picture of there install? it would help me out immensely. Thanks

General mechanical knowledge here not specific to skylines

The altinator has the big power charging wire

And an altinator signal wire to say turn on and start charging

And it is earthed through the bolts to the engine

They are Usualy hot from the engine and being an rb they hold heat for farking ever

If your battery is hot as leaking

Replace it

Leaky battery's are not good ad it's it's hot it's the batt not the altinator

Altinator a either:charge, don't charge or get flogged out bearings

Have a talk to some other people but I would say replace battery

thanks for that. i got a brand new battery yesterday but decided to put the old alternator back in as I didn't want to ruin a fresh battery as i don't think it could be anything else except for the alternator. when I put the new battery in I did start the car with the new alternator just for a minute to see if the battery indicator lamp still lit up which it did.Will get it tested and let everyone know what the problem is.

Sounds like it's over charging. When the alt light is on it usually means they're either not charging or over charging. There should be two smaller wires going to the alternator L and S

L = light, S = sense. If you don't have the sense wire connected the alternator will output 12 to 17v, which will cook your battery nice and quick.

Test the voltage across the battery terminals with a multimeter it should be around the 13.3v mark if it's not then its most likely stuffed. Put the new alternator in and start the car, check the voltage again across the terminals, if it goes over 14.5v then its over charging. Other then that there is not much else that it could do to wreck the battery. I just think your old battery has had it.

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