just get a new alternator and do yourself a favor.........
the diodes let electricity run one way.. from the alternator to the battery.. if you have a bad diode then the juice will run out of the battery back to the alternator and your battery will go bad.. if you have to ask
questions like this tben you dont know enough to work inside an alternator.. and where are you gonna get diodes and will they be the right kind??? some diodes that they were using in the 80's ford cars had to be high temp. diodes.. the remanufacturing places were using just regular diodes and the replacement parts would not last............