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Anyone rebuild their 4.0 XJ starter?

tkotitan

NAXJA Forum User
Location
Vermont, USA
I have a 94 XJ - 5spd 2dr 4.0L

The solenoid is sticking often on my jeep. Seems temperature dependent. Also, the battery is tired, but is running fine now that temps have risen. it seems weather depending and both humidity and temperature fluctuate wildly in Vermont.

Thankfully, I can reach it from the top, I have a 3' steel carpentry tool that I can bang on the starter with. I have to do this hard, and may be denting the housing. The filter adapter used to leak all over this starter but we fixed that last year so now it is just grimy. Would even cleaning the outside help?

I am super broke and wondering if I should just live with banging on the starter. Or, could I remand it myself.

Has anyone specifically done this for a 4.0L starter? Would taking it apart and cleaning it help the solenoid from sticking?

The symptom is no click on key turn. Then I bang on the starter, sometimes it starts, often it clicks first try and then second try it starts. Sometimes I have to keep trying the key 3 or 4 times with clicks before it starts. But usually only one.

At least it is a 5spd so I sometimes strategically park and roll start it. Helps keep the battery charged since I do many short trips and as I said the batter is old.
 
It may have little or nothing to do with the solenoid. The solenoid has two functions, one is the main contacts for the motor itself and the other is to mechanically push the main drive gear into the tone ring or flywheel teeth. The solenoid and the Bendix work together to help the drive gear into the tone ring or flywheel teeth. If the starter doesn't spin up, the contacts in the solenoid may be making contact, but the motor brushes aren't making good contact, the motor won't spin up and work the Bendix. The whole process can stop right in the middle and you may not hear the typical click from the solenoid, which doesn't mean the solenoid is bad.

And oil covered starter may mean the brushes are oil coated, the oil seeps inside someway. Submerging the starter in muddy water can also coat the brushes, it dries and makes for iffy contact.

The brushes have a lifespan, it really depends on how many start cycles, over a period of years, the starter has as to how long the brushes last.. Dried mud, sand or whatever is also an abrasive.

That temperature dependency may be related to oil covered brushes. Oil gets thicker when cold, thinner when warm. It may be a combination of oil covered brushes and short almost worn out brushes.

Most guys opt to by a rebuilt starter with a full guarantee and just replace it (on the guarantee) when or if it screws up again. The brushes kit for the starter cost more than half of what a rebuild costs (typically), Not really cost effective to rebuild one anymore.

The low battery is also likely an issue, the lower voltage has more trouble burning through the oil covered brushes and/or forcing a contact (arch) between the brushes and the commutator (the commutator is what the brushes push against while it rotates). Battery poles and grounds are also a factor, if they aren't clean they pass less amperage and/or voltage.

GoJeep.com has a write up on disassemble, cleaning and reassembly, but his site is down right now.

You may want to do a search, somebody posted a site with a budget set of brushes and the mounting plate not long ago. The brushes are cheap, the mounting plate not so cheap and a necessary part of swapping the brushes out. You can do the brushes without swapping the mounting plate out, but it is a pain and reliability may be iffy.

I saw one solenoid that had a torn rubber seal, the piston in the solenoid was a ball of rust. Getting the solenoid apart can be rough, the screws tend to chemically bond to the body of the solenoid and can be a beatch to get out without screwing them up. I've replaced one (XJ) solenoid in 25 years, my guess is they don't wear out or fail very often.
 
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Ten years ago I took apart the starter in my neon and cleaned the gunk out of it when it wouldn't work, got another three or so years out of it no problems. It is possible to mess up the reassembly though.
 
Ok, the starter finally died yesterday. I can find a replacement on eBay for 56 bucks shipped with a 1 year warranty.

So now my question is, what exact tools will I need to change the starter myself? I have found some guides online, this looks like a pretty good guide that gives sizes.

http://mikestrawbridge.com/blog/2010/04/xj-starter-replacement/

So I need an 8mm, a 13mm, a 15mm and a 9/16 bolt removal tool.

This may seem like an anal question but I lack tools. My friend who will help me and is much more handy also lacks tools because an addict sold them. So I am wondering if crescent wrenches would work, or does this job demand a ratchet and sockets?

Also, can I get away without jacking up the rig on a stock lift? Would prefer that for safety's sake.

And for those who want the full story of how it died:

I have been banging on the starter to get it going for a while (see above). The past couple days it has been trying harder and harder to start once it is unstuck, like attempting one fire and then starting on the second fire. It had been doing that for a week or so. The dummy lights flickering tells me it's working hard. So yesterday, it would stick, I would bang on it, and it would try to start, sometimes just give a low whur, other times, just flutter and the lights all flicker. So it's dead.

Thankfully I can still push start it in a pinch. Gotta love these old rigs.
 
Oh also of interest on how it died, I did switch to full synthetic oil and immediately it began the pattern of always taking longer and starting on the second fire. So perhaps the resistance in the motor changed and this required more effort to start it? You would think it would take less, but with a dying starter maybe not. You could postulate that switching to full synthetic did my starter in, in the straw-and-camel's-back sense.
 
pretty sure you are over-thinking things here. the starter was shot, the oil change had nothing to do with it.
before your starter shows up try to get under there and loosen things up. you can do the job with a good set of box-end wrenches.
 
Are you SURE that your starter is bad? I thought mine was a while back. Turned out to be the STARTER RELAY. It's a small metal box that sits in front of the rest of the relays on the passenger side fenderwell.
 
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