ElianM

My 2000 model Cherokee Sport began hard starting a few weeks ago. Not a daily driver so I didn't bother with checking anything thought I will get to it later. Later comes and it barely cranked. Checked battery voltage and it was below 12 v. I jumped it with another vehicle and drove it to the store and back roughly 6 miles, shut it off tried to start again and it fired right up. While it was running I pulled the + cable off battery and it remained running. Few days later, same thing, barely cranks engine over and finally nothing. The battery in it was 5 years old so I went ahead and replaced it. Started right up and I drove it on short trips for several days. Today I tried to start it and nothing, zip. Checked (new) battery voltage and it is at 12.47 volts. Radio, lights etc all work. If new battery voltage would have been extremely low I would have thought immediately that something obviously was draining it but the voltage is good. Engine also remained running after disconnecting + cable so I would think the alternator is good. The combination of earlier hard cranking and now with new battery virtually no cranking when turning the key has me leaning to the problem being the starter. I don't like hanging parts on something until its fixed and this being my first Jeep I don't know a lot about them. Any ideas or anything else I ought to be checking with the symptoms described in mind? I'm so busy running a business I hardly get the time lately to work on it. Also wanted to add, two instances when starting it up at idle it stumbled, etc with very choppy idle and didn't want to stay running when I tried to give it gas. This all happened prior to me replacing the battery. Very odd because it had never done it before and did not do it again before battery replacement. I also noticed what sounded like a belch from the intake system several times while trying to start it today.

BlueRidgeMark

What's the voltage when it's running @ idle?

And why in the world would you pull the + cable off while it's running? Bad idea!

ElianM

I did not get to check it today with the new battery since it will not start. Anything 2000 or older should be fine to see if alternator is doing it's job by pulling positive cable with engine running. Right now I have a fully charged new battery but it's doing nothing. It is that fact combined with some of the prior symptoms that has me a bit perplexed.

s346k

i would start by checking all of the cable connections and grounds. battery, power distribution box, starter etc. cycle the key on/off twice next time you attempt to start it. the stumbling and rough idle may be a simple fuel pressure loss prior to starting.

ElianM

I will try that. I would have thought that the 12.47 volts would have at least been enough to get it to crank over aside from a secondary issue but obviously something is amiss on the primary side of the electrical system. Whatever it is it killed the old battery and is draining the new one. You turn the key and you get a very weak cranking for not even a revolution of the engine and then it goes dead, nothing(just like a weak battery). Meanwhile the battery voltage is enough that it should at least crank. I went through and made sure grounds were all good when I put the new battery in and also put new cable ends on it and made sure they are tight. Not used to having a vehicle that has a hard time cranking but the battery is good. Usually when it cranks like this one is I find that the battery is very weak. To me that seems pretty strange though I'm sure to you guys who know these vehicles far better than I do it doesn't necessarily seem odd at all.

s346k

mine had the same symptoms; good battery and slow to crank. i replaced all of the cables (and ends) and grounds i could find. it remedied the issue and will fire almost instantly.

exasemech

carefully check that little jumper (usually a piece of copper braid under a length of insulation) that goes from the starter solenoid to the starter motor. The braid tends to rot in salt etc and the rot may be hidden under the insulation or may look OK but barely conduct. It may have been messed up when you changed cable ends.

ElianM

The only body ground I see on it is right near the battery and I replaced and resecured that one. If there are any others I don't know where they're located.

ElianM

Thank you for that info, I had not at all thought of that.

fb97xj1

This may not be it, but check the starter. When they get covered in enough dirt and oil, they can be slow to crank, or not crank at all. Just something to rule out, should this happen later on down the road.

ElianM

As pin clean and rust free the rest of the underside of this Jeep is, the starter is indeed covered in a layer of grease/oil. Thanks for the tip

BlueRidgeMark

I don't know where you got that idea but that is flat wrong. It's a crap shoot if you'll fry your alternator that way.

tjwalker

Agree with BlueRidgeMark.....this is an old trick used by mechanics prior to modern day electronics. It may have worked with my 1966 Chevy, but good luck to you on your XJ. It can absolutely positively fry alternator, computer, etc. I have repaired a couple of these misadventures for people that have tried this and failed. Expensive mistake.

Read this short article to understand why this isn't a good idea. A simple voltage meter will usually tell you most of what you need to know if your charging system is working or not. And without risking fried components. Don't do it.

http://www.troubleshooters.com/dont_...ct_battery.htm

ElianM

Okay thanks for the correction on disconnecting the battery cables. I was told that so long as you only do it at idle and don't rev engine and over-run the regulator it should not hurt anything but I'd rather be safe than sorry. Right now the battery is reading 12.5 volts with engine not running. I would think that should be enough to at least crank it over but when starting it, I get one very sluggish slight turn of the starter and then nothing. Turn key off and then turn it again and zip. Let it sit a day and try again and another sluggish attempt and then nothing again. All things considered that leads me to believe the problem is the starter. I will recheck all connections, the strap from solenoid to starter motor and grounds and then try jump starting it again. If I can get it running that way then check battery to see if alt is charging it.