[jimk127]

I upgraded to a 3G, 130 amp alt a couple of weeks ago. It is used, but tested good on two different occasions, 15.2 volts. The car has been running fine since the alt upgrade. Today I drove the car about 5 mile with the A/C on, fog lights on, and the stereo w/ 4 channel 90W x 4 mildly cranked. After being parked for about 30 minutes I tried to start the car up but got nothing, not even clicking. The car started right up with a jump. I drove the car home, about 5 miles, with only the head lights on, shut the car off and started it right back up with no problem. The battery is a few years old. It is not a top of the line battery. Is my battery going bad or is the alt not charging?

 

[SeanD]

I'd say a loose wire?

 

[leonbray]

What is the voltage reading with the engine running ?
Can you get the battery tested at your local parts store?

Intermittent starting problem could also be

loose battery cable
loose or broken ignition wire to solenoid
bad solenoid
bad ignition switch

My guess would be battery if it is a few years old.

 

[69KATT]

i would look closely at the battery also. you could take it to the local parts store and get it load tested just in case. If you do purchase new battery, be sure to save reciept. I've had top of the line batteries crap out after only 1 yr.

My father put a new top of line sears batt in mothers car, it took a dump within a year. (couldn't get it to charge when I was there). It got replaced under warranty at very little cost. I was very suprised he had the reciept. Turns out he still has the paperwork for the very 1st house he ever bought, every car over the years... he saves everything. Has a 4 drawer filing cabinet with everything neatly saved and filed. Something I should start doing...

 

[Bad69cat]

Can't add much to the above - did you actually test that the regulator is working after the conversion? Quick test is to disco the + batt post while the car is running - if it dies you aren't getting juice via the regulator for some reason (or the alt isn't putting out anything....) In that case you need to investigate your wiring a bit more.

 

[jimk127]

Good input, Thanks.
The voltage at the battery with engine running is over 14V.
The wires are in very good shape and connections tight and clean.
I will test the reg by disconnecting the + bat cable from bat.
I will also have the battery tested.

 

[Jan Ove]

Can't add much to the above - did you actually test that the regulator is working after the conversion? Quick test is to disco the + batt post while the car is running - if it dies you aren't getting juice via the regulator for some reason (or the alt isn't putting out anything....) In that case you need to investigate your wiring a bit more.

And that method is also a great way to ruin a modern alternator, and also other parts of a ignition system, if you have an electronic ignition

 

[jimk127]

The volt reads acroos the battery were:
Bat eng off 12.35
Key on (not running) 11.81
Running at idle (no accessaries on) 14.3
Running at idle (all accessaries on) 12.5
Running @ 2000 rpm (all accessaries 0n) 13.5
Running @ 2000 rpm ( no accessaries on) 13.95
Bat after test Engine off 12.78
The battery tested good at Azone
12 + volts, 89% charge, load test was good.

It doesn't make sense to me why I had to jump start.

 

[leonbray]

Do you have power to lights, radio, etc when you tried to start it up?

Could it have been solenoid not kicking in?

How about the neutral safety switch? Might not have been fully in park and fooling around or moving the selector managed to put the selector in the right position.