'96 wouldn't crank over? Started a couple minutes later...

1996 Cherokee Sport, ~160K miles, Manual Trans, 4.0L

Just did a quick run to drop something off. A few miles on the freeway, maybe a mile of surface street, then stopped for five minutes. Get back in and it won't crank over. Tried several times. No luck. Got out and popped the hood to check connections. Everything looks just fine. Get back in and try again, still no crank. Wait a minute and suddenly it is willing to crank. Starts right up. Got back home, tried after I parked and it was willing to start then. It will start now. My Google-fu isn't giving me any good suspects.

A previous owner has taken out or bypassed any clutch and neutral safety switches. You can start this vehicle in gear if you aren't paying attention. It may be worth my while to try to figure out how they bypassed those as the PO was no wiring genius. Any input as to where those safety features were supposed to be and what colors of wires I should be looking for would be appreciated.

For that matter, what all is in the starter circuit? Starting at the battery, what various relays and switches are in line?

Looks like I am going to get a quicker education in the workings of this vehicle than I intended to. It might be simpler to just install a remote starter switch.

crappy battery connections will do that. even if they are tight and look ok, they can be pitted inside or under the connection.
pull the terminals off and clean them real good. replace them if they are old and scarred or cracked.
what happens to the rest of the vehicle when you turn the key and it does nothing? do the gauges and lights go dead for a second?

I am quite confident it is not the battery connections. Just a couple of months ago I did this: http://www.naxja.org/forum/showthread.php?t=1108471

I doubt it is the battery. That would be too convenient.

The problem is going to be either a poor connection or high resistance due to heat. Or both.

I have no idea as to the age of the starter. A new solenoid is looking like a prudent move in my eyes.

I can't speak to what the rest of the vehicle was doing while it was not behaving. I was in a bit of a panic on account of the timing/location of the problem and the fact that I had the kids in there too. I didn't get as far along in my diagnosis as would have been prudent. I will definitely being paying attention to those details if it occurs again.

I usually figure anything over 130,000 miles and the starter brushes are questionable. It really depends on how many times you use the starter and how much wear is on the brushes. If the starter is covered in oil, oil can seep inside, this makes starts an iffy thing, the oil finds it's way inside and coats the brushes. Oil coated brushes sometimes work and sometimes don't, the same with well worn brushes.

Solenoid is far down my list of possible causes. Delco, Ford and Chrysler solenoids used to be a regular trouble spot, not so with the Bosch Mitsubishi starter. I've had a Bosch solenoid on the shelf in my shop for twenty five years and never needed it.

I appreciate the input.

Sounds like it might be worthwhile to order at least some brushes:

http://www.aspwholesale.com/index.php?act=viewProd&productId=7536

and

http://www.aspwholesale.com/index.php?act=viewProd&productId=2899

Or should I go for the whole rebuild?

http://www.aspwholesale.com/index.php?act=viewProd&productId=5985

Most of the guys go for a lifetime warranty rebuild at one of the larger parts outlets. And swap them out (for free) when they fail.

I buy the brush kit with the two brushes, the mounting plate and the other two brushes that go with it (4 brushes total). The reason is the springs loose some tension over the years. And other than the brushes, OEM starters rarely screw up. A rebuild is kind of a pig in a poke, there is the odd overrunning clutch that fails, or somebody at one time or another has overheated the windings etc. that they may have failed to notice during the rebuild.

I always keep a spare (junkyard) starter around and take one with me when mudding and/or for a long trip. I have an auto, hard to push start an auto tranny.

The down side of the mounting plate and brush replacement is it can cost almost as much as a rebuild. But at least I know what I have and it takes some of the guesswork (and luck) out of relying on somebody elses rebuild.

The kit in your link looks like a good bet, depending on the price. Like most kits it gives you some unnecessary stuff and some of what you actually need. I don't really know how much I'd trust an aftermarket, cast, starter fork. The bearings in an old starter can get really sloppy before they cause issues. You are more likely to need a drive gear and overrunning clutch, which isn't in the kit.

You did mention a wiring issue with your XJ. On my 96 somebody left the solenoid connector at the starter loose sometime before I bought it, it eventually overheated and melted down the end of the connector. I put new old style (separate) connectors on the end instead of the one piece connector and replaced the whole starter relay to solenoid wire. The solenoid wire was really stiff for almost a foot, indicating that it had cooked at sometime. You don't have to replace the wire all the way back to the relay, there is a handy plug a few inches outside of the PDC for that solenoid wire. You will notice the wire and single wire connector sticking out of the PDC is like 16 gauge (a guess) wire and way undersized for this application. Not much resistance in a solenoid, amps are what make it work, hard to get sufficient amps through a tiny wire without things heating up. Something to look at anyway. In my experience 9 out of 10 times it is the brushes.

I posted the measured length of a used up brush and a new brush sometime in a past post and neglected to write it down. Maybe somebody remembers, I sure don't (getting old sucks).

Thank you for the detailed response.

I am of the same opinion on rebuilt units being a pig in a poke. I would rather work on what I already have and know what I am dealing with. I think I am going to order some pieces and play with what I already have.

Yes, I have noticed that factory pigtail coming out of the PDC and being substantially smaller than the green wire running down to activate the solenoid. I have plans to tear into the PDC and make some changes in it. I may upsize that wire while I am in there. I just wish I could get my hands on some new factory terminals.

I would guess bad brushes or solenoid contacts. Either way, one suggestion if you need to drive it awhile before rebuilding is to carry a nice big stick, bat or iron bar. If it fails to start again, open the hood and bop the starter with the bar. If it's a poor contact, it will usually come to life. If this does fix the problem it's a good indication that you need to get in there and fix it.

When it fails, have you tried disconnecting the CPS (or disconnecting the battery) for 5 mins and try again?

It seems your NSS was bypassed, so that's why you can start the Jeep in any position. Not a real problem if you always start and stop it in P/N.

Zapa89 said:

When it fails, have you tried disconnecting the CPS (or disconnecting the battery) for 5 mins and try again?

It seems your NSS was bypassed, so that's why you can start the Jeep in any position. Not a real problem if you always start and stop it in P/N.

Click to expand...

The CPS will keep it from starting, but not from cranking.

Of course in such discussions we must allow for vagueness of language much of the time, but given the original post I'm assuming that this is a "no crank" issue, not a "crank no start" one, which is sometimes mis-characterized.

Manual Jeeps do not have an NSS. At some point, I think in 97 but it's a guess, a clutch switch was added, so you must push down the clutch to start, but this can be in any gear. My 95 had no such switch, my 99 did. My son had a 96 and my recollection is that it did not. The entire pedal linkage was changed in 97. On the 99 the switch was on top of the pedal arm. It shouldn't be hard to figure out if there is one there.

I got rid of my clutch switch, a nuisance. The main problem if you have no clutch switch is other people, who are in the habit of leaving a car in gear with the brake off. Terrible habit on a manual.

Matthew Currie said:

The CPS will keep it from starting, but not from cranking.

Of course in such discussions we must allow for vagueness of language much of the time, but given the original post I'm assuming that this is a "no crank" issue, not a "crank no start" one, which is sometimes mis-characterized.

Manual Jeeps do not have an NSS. At some point, I think in 97 but it's a guess, a clutch switch was added, so you must push down the clutch to start, but this can be in any gear. My 95 had no such switch, my 99 did. My son had a 96 and my recollection is that it did not. The entire pedal linkage was changed in 97. On the 99 the switch was on top of the pedal arm. It shouldn't be hard to figure out if there is one there.

I got rid of my clutch switch, a nuisance. The main problem if you have no clutch switch is other people, who are in the habit of leaving a car in gear with the brake off. Terrible habit on a manual.

Click to expand...

Yes. To clarify, this was a "no crank" issue.

It has yet to repeat itself. I have just taken out the starter and replaced half of the brushes. The negative side brushes are resistance welded to the retainer plate, so you either have to have the resources to duplicate a copper to steel resistance weld or you have to replace the entire brush holder assembly. The positive side brushes are a much simpler matter.

Fortunately, the positive side brushes were the ones worn down the farthest. The negative ones measured 0.5300" and 0.4550". The positive ones measured 0.4060" and 0.4245". I replaced the positive side today and will be back in there again to replace the retainer/negative side assembly.

I will do a write up on the starter brushes once I get my act together. I think carrying a set of the brushes may make sense for some folks.

I also replaced the solenoid.

We will see if the issue repeats itself. I am hopeful the worn positive brushes were the culprit.

Thank you for the information on the lack of NSS. I had intended to go searching for the bypassed switch. It would have been a frustrating search. I am surprised the lawyers let them produce such a vehicle all the way into the mid '90s. I expect it on older vehicles, but usually those who know what's best for me have taken my choices away by the late '80s.

I hope the starter repair solves it. I suspect it will. The electrical shop that rebuilt my starter included a new or renewed end plate, with a new bushing. I don't know how the upset weld can be duplicated at home. At a certain age, that little bronze bushing can cause some issues. If you have a good starter and generator rebuilder in your area I would suggest that if problems recur you take it there rather than getting a mystery in a box from the parts store. The best of these guys will do a thorough job for less, and it will hold up well even if it is not as pretty looking.

I am hopeful that it is solved.

Today I ran it through the same routine that caused the problem the first time, and it did not repeat. I took along a bump start switch just to be safe. Murphy says if I put that switch away the problem will suddenly recur.

When the new back plate comes I will be in there again.

The nice thing is, this has got to be the easiest starter I have ever pulled. Very easy access and doesn't weigh as much as a Jap transmission.

Tapping on the starter while someone was holding the key in the crank position would identify bad brushes by "shocking" them to make contact with the armature.