Inspect the alternator you're taking out to make sure it wasnt' fouled by engine oil. If you've got an oil leak that is dripping onto the alternator, you'll need to address that 1st or each replacement alternator will suffer the same fate as the previous one. Do voltage drop tests to check the integrity of the battery to alternator wire, as well as battery to chassis, and block to chassis. Good LUck!

Joel, CA