Dont bother with an exchange unit. Your alternators brushes will be the fault. Buy or reclaim some brushes from an old starter motor and file them to fit the brush pack from the back of your alternator.
vince
November 2012
the fault is in the the alternator not battery need to check the alternator output using a DC voltmeter,measure across the battery terminals with the engine running, you need to see around 13.5 to 14.5 volts with a good alternator, anything less than this alternator is faulty exchange unit required
wirecutterman
October 2011
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