GM-GMC: Alternator, chevy suburban, light hook

Question
okay i am having some alternator problems, however i do not beleive it's the alternator....changed it....battery tested good....car keeps dying every two blocks....get a jump..truck starts...two more blocks it dies again...PLEASE HELP!

TRUCK IS 1988 CHEVY SUBURBAN 350 FI ENGINE

Answer
This does sound like a alternator problem, when it dies and you get a boost the battery gets a slight charge. this is the charge that gets you the 2 blocks and it will die again. this indicates that your alternator is not charging the battery. Two things to check would be:

1) Make sure the large gauge red wire in the back of the alternator had power all the time. Best to use a test light hook the clamp to the (-) batt terminal and probe the stud the wire hooks on to test light should light.

2) there should be a nother electrical connector in the back of the alternator, this is for the field circuit. Basicly a batt.voltage signal to the alternator telling the alt to start charging. Don't worry about witch wire is witch if multiple wires in connector. Just use test light as in the #1 test and probe the wires and get a helper to work the key. You are looking for the test light to light when the key is turned to the start possition.

Many times I have seen fusable liks burnt out if the battery is not disconnected when the alt. is changed and the red power wire momenteraly touches ground, if you are missing any of the above powers check your fuses first and then the fusable links might be a good place to go after.