won't start after replacing alternator???

[Dexter Shark]

After about 4 months of procrastinating I finally replaced my alternator (it was overcharging). After installing it, I reconnected the battery and it basically started right up. I drove it around the block and parked it in the street. When I went to park it back in the driveway, I turned the key and there was nothing. I'm assuming that either something is shorting out or else the battery got drained because i hooked something up wrong. Any suggestions? I'm not mechanically inclined and a period of 2 months went by from the time I took the old alternator out until I put the new one in so I tried to connect everything as I remembered it.

[reddog]

Check your wiring at the alt and also the starting relay. The relay is on the passinger side wheel well in the engine compartment.the positive battery cable goes to it. Does your battery have juice?? Check the battery cables' connections. Do the lights etc work? Or is everything dead??

Kerry

[Dexter Shark]

No lights everything is dead. I'm not about the wiring to the alternator (I'm an idiot), I was trying to remember what went where and it had been a few months so I might have forgot something. There is a plug connection that I connected and some wires near that I secured. There is also another bolt on the back of the alternator, does something get connected there? I didn't see any loose wires, but I can't remember if I took something off there. My positive battery cable could use replacing I know for sure, but the jeep did start up initially and then 4 hours later everything was dead so that has me puzzled. Thanks for replying.

[PhilSine]

4 things that may be causing your problem listed in order of possibility.

1) Connection to/from battery, either pos or neg. This is caused by
a) loose battery terminal post
b) loose or failing cable on battery
c) loose or failing cable at engine block (neg) or starter solenoid (pos)

2) Fusible link failure. The fusible link will be located on the yellow cable that attaches to the starter solenoid that also shares its post with where the pos comes off the battery. It should be within 6" of the lug and may be burried by some electrical tape.

3) An open in the red wire from the battery to the instrument cluster.

4) Ammeter failure. You can verify this by removing the instrument cluster, disconnecting the yellow wire from the back of the ammeter, and placing it on the same lug as the red. This will simply bypass the ammeter and cause no harm to your system.

All of the above will cause a general ignition failure but the symptoms of the ammeter will not inhibit the ability of the headlights to turn on. You could also have a dead battery caused by any one of the following.

1) Left lights on (simple but I had to mention it)either headlights or a dome light. Based on what you described I doubt it's this one.

2) Red cable from alternator is not properly connected and not charging thus draining your battery.

3) Previous strain on battery has caused catastrophic failure resulting in battery's ability to accept adequate charge.

4) The battery, having been constantly overcharged, ran low on fluid and no longer works properly and, consequently, won't charge.

When you do get it running, stare at your ammeter. It should always be to the right of center after the initial recharge from start. When you first get it going again, the ammeter will peg to the right and gradually move towards center. Check your system charge with a volt meter. Your battery should be maintained at a charge between 11 volts and 15.5 volts. If you measure alternator voltage with it off the battery, it will typically be well above 15 volts and sometimes up around 16 volts. This is normal. When the load of a battery is placed on the charging circut, the voltage should drop to an output within the normal stated range.

[Joe H.]

That bolt on the back of your alternator is the battery terminal. It must be connected in order for the alternator to charge the battery. See if you can charge your existing batt or swap one in temporarily. If you have juice, connect that terminal! If not, it's probably the fusible link.