Alternator failed

[colb]

No sooner I put the tools away from replacing the exhaust downpipe bolts going to get them out again, alternator failing, not charging made it home with 11 volts. Alternator was a used one I put in whilst my original was rebuilt last year so the rebuilt unit is in the garage wondering if I should just change the diode pack or change the units over less work just changing the diode pack. Think I will change the units then have the duff one rebuilt as a spare. Use a local Alternator and Starter rebuilder who is very resonable and uses oem diode packs when servicing BMW Alternators.

[colb]

Spare rebuilt unit fitted today charging resumed cleared all the codes that were generated by the power outage but now spotted a weeping O rig at the bottom of the expansion tank on the side of the radiator. Will order a pukka BMW O ring so leaving the front undertray off till I get the replacement.
Will have my local man rebuild the failed alternator to keep on the shelf just in case