Jeep starting problems

OnlyOneKeano · 11-22-2009, 09:43 AM

Have an old jeep J20 trying to figure out why its giving me problems... if anyone has any ideas please respond.

here's the problem. few mornings in a row found that battery voltage was below 10 volts..., couldnt start the thing. Jump started it and it wouldnt start, starter would just click away everytime i tried. Untill I charged the hell outta the battery with the other vehicle. After charging the hell outta it finally got it to start.

Next morning same problem.. Used an inline amp meter to see if anything was drawing on the batter. nothing. Looked at the date on the battery it was really old.
Buddy of mine has an old battery 'test meter', checked the battery and it indicated the battery condition was really bad. Considering its 5 years old, it makes sense, aslo considering I use this vehicle for alot of short hops.

Changed the battery, everyhting was fine, ran good for a few days, now its doing the same thing... now even when i get the battery up to 12 volts, starter stilll clicks away, cant get it to crank over at all.

Its seems quite obvious teh starter is done and needs replacing, and thats ok. But will a pooched starter slowly discharge the battery? like overnight?

Has anyone ever heard of a worn starter discharging your battery overnnight? anyone got any ideas?

thanks alot.

WaveHunter · 11-22-2009, 08:51 PM

I'm not sure. Have you tried to disconnect the starter cable from the solenoid and see if it still drains your battery? That might help isolate the problem. I don't know if we can blame it on the starter unless you know it is bad, then you would need to replace it before diagnosing further. There are other ways batteries can drain overnight, and usually the starter isn't getting juice until you turn the key. The starter solenoid might be a more likely suspect. It's hard to tell without narrowing it down by the process of elimination, and electrical testing. I'm no expert, so maybe someone else can chime in and be of more help.

semikrazy · 11-22-2009, 09:25 PM

Are you sure the alt is charging? Disconnect the battery, either side, and when it is dark outside and with key off touch the cable to the battery like you are hooking it back up, does it ark at all. If so you have a draw somewhere. If you get a new starter make sure the starter mateing surfaces are clean and free of oil. It can cause a bad ground and cause it hard to start.

jeepdaddy2000 · 11-22-2009, 10:18 PM

Since you didn't fill out your profile, I'm going to assume we are working on an alternator. Buy a volt meter.With the engine running, you should be pushing 13-14 volts. If so, your charging system is good. Clean and inspect all cables and grounds. Check the solenoid. I don't know which style your running, but if it is a fender mounted one, turn the switch to start (make it click) and see if you have juice going through the solenoid to the starter. If not, your solenoid is bad. If so, then you need to take a look at your starter. Later Ford style starters will act this way if the brushes are worn.

carnuck · 11-22-2009, 11:30 PM

Are the belts tight? What's the voltage when the motor is running?

OnlyOneKeano · 11-23-2009, 12:12 AM

Hey guys...

semikrazy--> I tried that trick last week when i realized i was losing battery voltage over night. no arking at all. Also hooked up my multimeter inline to see if it was drawing any amps. Nothing.

well i went to jump start it this morning and it wouldnt start off the other vehicles battery. I'm sure if I stayed there long enough and charged it with the other vehicle it may have. I got it up to about ten volts (wouldnt start) but i thought i'd leave it int here for a while to see if it was drawing. Within two hours it was like down to 8!!! but i still cant find out whats causing it. From what i can tell thers no draw on the battery!

I ended pulling this battery, which is brand new, stuck on the charger for the day, and re-installed it. SOmeone also told me my problem could be caused by a leaky diode in the alternator. The alternator will charge your battery fine (which it is, somehting like 14.4) when the engines runnig but when you shut it down itll suck you battery down.

So i disconnected the alternator and its gotta fully charged battery in it. I'll see how it is in the morning and update you guys.

thanks alot. Its a jeep J20 btw!

OnlyOneKeano · 11-23-2009, 12:13 AM

BTW when i stuck the fully cahrged battery back in it today, it started up no problem.

carnuck · 11-23-2009, 12:35 AM

If you have the cable off overnight and the battery does NOT drop, then the battery is fine (don't accept that a new battery can't be bad! I just sent 6 back that were NFG right off teh delivery truck!)