New alternator, checked out good, new battery, checked out good Checked all wires but alternator is still not charging. I was told the voltage regulator would cause the alt to overcharge. should I try to replace it? Battery dies after about 3 days with no lights or radio running. HELP

 

Either you have a voltage regulator internal to the engine computer, or an external, Depending on you van's year, which you do not state.

Checking wiring is not defined by looking at what you can see, but testing it for continuity between ends, and determining if any wire also has continuity with ground, which most should not.

You need to get a Digital multi meter, and do some testing.
Specifically battery voltage before starting, after starting, and measuring the voltage on the back of the alternator when running.

Until we know more I will GUESS that you have a bad ground wire from battery to engine, engine to frame, or battery to firewall, or the fusible link behind the brake booster has failed.

Also, batteries hate being below 80% full and will quickly lose capacity if left below 80%, so do what you have to to keep that battery full, until you find why it is being depleted.

 

Thank you very much for the solutions. Bought a meter, tightened battery to engine ground, replaced external voltage regulator. Registering 13.9 to 14.5. The beast is on the road again. Again I really appreciate the response. I am a carpenter, not a mechanic, but with your help I saved big money.

 

Glad it worked out for you!

They say 85% of all electrical issues in vehicles are caused by a bad ground. Sometimes components fail which require a good ground, like an external voltage regulator.

Since I helped you save money please send 20 bucks to:
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