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Alternator Problems? Some Answers Inside

Dan_J

By Dan_J,
in General Maintenance

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Dan_J Veteran

Dan_J

Posted
Posted

so on my c34 stagea daily i was getting inconsistent charging results, while on idle i would get about 12.50v , with some revs low 13's.i cleaned and sanded all battery and alternator terminals with no luck. i figured the alternator was bad so i swapped out the 80amp c34 for a 90amp out of a r32 rb20, after a test there wasn't much of a difference.

so i headed down to the local auto electrician at cherry automotive, and they had a look at the terminal just off the alternator.

at the terminal on the alternator it was charging fine at 14v yet the battery was getting mid 12's. i was told to run a 2nd thick wire from the positive in the alternator to the battery.

i headed down to the wrecker's and grabbed a thick starter motor wire ($4 bucks) off a ba falcon,one side already has a lug to suit the battery and the other i just used some big battery lug from jaycar. trimmed to suit length, just crimped it on a vise and now charging at 14v on low idle so battery is getting max voltage where most have to rev a bit higher to make volts climb

figured i'd post this up as it may help a few and its a good way to rule out other problems

mods can decide where this thread should go

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Mick Mentor

Mick

Posted
Posted

wow thats pretty good work there, i have a bad alternator and i was getting ready to put a new or secondhand one in but after reading your problem i will try that first, i have an r33 so my battery is in the boot so i first might try just running a second wire from alternator to the engine fuse box cos it has big terminals on it meant for jumpstarting

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