Mitsubishi Repair: 1995 Eagle Talon 2.0L non-turbo, 1995 eagle talon, power surges

Question
After an engine swap, by mechanic,alternator will not charge.  Same engine swap, have had alternator checked, mechanic has checked fuses and wiring.still won't charge.
Help please, what have we not done or checked. Could the computer not address the change and not allow it to charge?

Answer
Kent: Not sure if I can be any help to you or not. You said the mechanic checked the fuses and the wiring. Has anyone checked the battery to make sure it has a full charge, are the cables tight? Is the belt that drives the alternator in good shape and is the alternator tighten down as it should be? Could be the voltage regulator is bad or not the right one for your car. As my manual says the alternator comes in 60, 75 and 90 amp output ratings and so maybe the alternator you have is not the right ratings for your car. You should have your car coded and that would rule out any problem with the computer. It could be the computer is not reading the alternator. It could be a relay, has the mechanic checked those? When you open the hood of the car, those black boxes one up on the driver's side by the fire wall, then two more on the other side of the car. They have larger fuses and relays in them. I would check all of them to make sure they are all in good shape. Sometimes we get so much into the big things that we over look the little ones. Such as what kind of shape is the battery in. Just get it tested, how about it's cables. I guess I would go back over the drive belt, how tight the alternator is well could be something is pulling away it's power in the form of a short. My manual talks about that voltage regulator is to limit the alternator's voltage to a preset value. This prevents power surges, circuit overloads, etc, peak voltage outputs. It says the drive belt and the battery service are the two primary maintenance requirements for these systems. It says if a malfunction occurs in the charging circuit, don't automatically assume that the alternator is causing the problem, first check the following items: the drive belt tension and condition. Make sure the alternator mounting and adjustment bolts are tight. Inspect the alternator wiring harness and the connectors at the alternator and voltage regular. They must be in good condition and tight. Note: be sure the to check the B+ terminal connector. Sometimes the connector will crimp and cause a voltage drop. It then says to check why the alternator won't charge... check the voltage regualtor, check the diode within the combination meter for a short circuit and also check the alternator relay. Also if there might be a damaged or disconnected wire to the relay. Check the wiring at the relay too. So this will give you some ideas to check. I hope you were sitting down then you read this as it is long. Hope it might help some and good luck! Linda :o)