Starter will not engage

98 4.0 Automatic

When turn key, starter does not engage. Can hear relays clicking. Have tried starting in neutral and shifting through gears while trying to start, with no luck.

Perhaps related, several weeks ago, had trouble turning key in ignition. Had the probelm for a few days. Jiggling the key in the ignition allowed me to turn the key and have not had the problem for a couple weeks.

Battery fully charged/load tested. Also swapped with 02 TJ battery. Both batteries start TJ, neiither battery starts XJ, so have ruled out battery problem.

Starter arced/spun when placing screw driver across terminals, but still would not start.

Started bench tested okay.

Have tested starter relay in accordance with FSM, all tests okay.

Need help understanding feed circuit test results. According to FSM, when testing voltage between battery B+ and starter B+, reading should be below 0.2 volts while turning key in igntion. I get 12 volts before turning key and while turning key. What does that result mean?

Suggestions for what to check next?

you're saying the starter spins but not engages to the flywheel teeths???

if thats' the case, the starter's needed to be replaced. or repaired. they're actually easy to be taken apart and clean/repair and reassembly.

however in my option easier is just turn it in as core and get a rebuilt one for liek $100 IIRC

Starter will only spin if I arc it, and then it won't start engine

how do you arc the starter? did you arc BOTH terminals? as one for the starter itself and other one is for the fork that lift the pinion gear into the flywheel teeth.

When you turn the key, you get only clicking? When you arc across the two terminals on the starter, the starter "whirrs" or spins, but the engine does not turn over? If this is true, the starter solenoid part of the starter is not kicking in. When the relays send current to the small wire on the starter, it is suppossed to make the solenoid push the starter gear into the flywheel teeth and let the big wire feed current to the motor through contacts connected to the solenoid. Pull the starter out and get it tested to verify this diagnosis. You can also verify after you get it out by connecting it directly to the battery with jumper cables. The motor will spin, but the gear won't push out.

Don't even hear a clicking, except the relays.

Correct that the starter whirrs and the engine does not turn over while arcing terminals.

Will pull the starter and test again tomorrow, checking this time to make sure the gear pushes out.

I assume that if it does not, starter needs to be replaced. Correct?

After grounding the starter case:

If you put 12V to the large post that is normally attached to the battery cable AND 12V to the small terminal next to it on the solenoid and the starter does not push the drive gear out and spin the motor, you need a new starter. If you send electricity to the big post that the battery cable is NOT normally connected to but not the small one (arcing across the big posts on the vehicle) the starter motor will spin, but not engage the flywheel.

since the starter bench tested ok,it sounds like you arced across the two big posts, but without being there, I don't know.

You could still be chasing a faulty NSS if what you're hearing is relays temporarily turning off as opposed to turning on. Try starting with your headlamps on and see if there is any noticeable dimming of the lights when you attempt to crank it over. No dimming would also be indicative of a possible bad NSS.

Jeeper64 said:

Don't even hear a clicking, except the relays.

Correct that the starter whirrs and the engine does not turn over while arcing terminals.

Will pull the starter and test again tomorrow, checking this time to make sure the gear pushes out.

I assume that if it does not, starter needs to be replaced. Correct?

Click to expand...

You are correct!

Pulled the starter and had it bench testeed again. Starter gear did pop out.

Was able to start by arcing the large post that is normally attached to the battery cable and the small terminal next to it on the solenoid. I had mistakenly arced across the two big posts. Thanks for the clarification on that.

Will that issues cleared up, moved on to ignition switch. When I pulled the switch, there was a small piece of metal in it that had broken off from what I will call a cam that comes underneath the stearing wheel from the assembly that holds the key cylinder. This piece does not appear to be named in the FSM and the the OEM parts dealer assures me that it is not a servicable part. The end of the metal cam fits into the ignition switch. When the key is turn, the cam turns, thereby turning the ignition switch.

1) Anyone know what the piece is called or where to get it? I know the boneyard is an option. Also know that putting in a starter button is an option, but I'm kinda anal about that kind of stuff.

2) I have a nagging feeling that I may have broken the part when I pulled the ingnition switch off. Although, it may explain the problems I had with turning the key earlier. To calm my fear, if the key is turned to the on/run position and I arced the starter, would the Jeep have started then? I had my wife turn the key to the start postition when it started, but don't know if arcing with key in on/run position would be sufficient to start.

if all is working in the ignition switch (electronic part) at the base of the column AND the ignition lock cylinder is functioning correctly, the vehicle would start and run when you jump the soleniod. If it will not start, I'd say the lock cylinder is no longer actuating the ignition switch as designed.

With the key in the run position, arcing the starter should make it crank and start up. If a flywheel tooth is damaged or broken off, the starter motor would crank, but not turn over the gas motor. Can you see in through the starter hole to check?

Well, you got a key, a key lock cylinder, a remote rod, an ignition switch, an ignition switch slider, and if you have a console shifter a Park-Lock cable and bracket.

So which piece is causing your problem? Sounds like the remote rod or ignition switch slider is broken. Determine which it is and replace, probably salvage yard.

Thanks Shorty and Winterbeater. The Jeep will start by arcing with the ignition in the run position. I believe you guys have confirmed that I did not break the remote rod.

Thanks Joe for the anatomy of parts. I believe the remote rod is what we are talking about. I tried a couple other parts places, just in case, with no luck. Also made a trip to the boneyard, also with no luck. They do have a couple of complete columns, so if I get desperate, I have that option.

I have a couple other boneyards to check.

I don't understand. The first line says you did not break the rod, the second sounds like you are looking for one in the junkyards. It does seem like the key is working like it should. Have you checked out the starter relay? What about the wire from the relay to the starter (the smaller wire)?

Winterbeater, sorry. The rod IS broken. My question about what position the key needed to be in to start by arcing was to determine if I may have broken the rod when I pulled the ignition switch off or if it was already broken when I pulled the switch.

Since the key only needs to be in the on/run postion to start the jeep by arcing the starter, that led me to conclude that the rod was already broken when I pulled the switch, and hence, the broken rod is the source of my non start. Is this a correct assumption?

Either way, I need to fix the rod. I have found a yard that will let my pull the rod from a column, so I am off to take care of that this afternoon.

fix the rod first and then go from there. It may start or you may also have other issues. You know the rod is broke so replace it and then re-test.

Rod replaced, Jeep starts as expected. Thanks to all for your help.

arty: