[MB968]

Don't know how the 968 system is designed, but: The only starter issue I ever worked on, the solenoid fired a large plunger/conductor into a copper target thus providing a very high current (over 200 amps) connection between the starter motor and the battery. This connection can be compromised with use, causing a lot of resistance between the plunger/conductor and the copper target. In the case that I had years ago on another car, this caused enough loss of current to make the starter motor not function properly. I was able to cleanup the plunger and the target, eliminating the oxidation from the surface. Problem solved. Don't know if you can just replace the solenoid, or it can be disassembled to check its functionality. A bad connection in the solenoid could be the cause of no power from the starter.

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[tamathumper]

Back when I had Gummy Starter Syndrome, I read about someone before me who had taken the starter apart to find it full of black dust. IIRC it would throw out the shaft like yours is doing, but it wouldn't turn. They cleaned it all out and the starter worked again, but as I recall it only lasted for a short while before needing to be replaced.

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[Cloud9...68]

I'll finish taking it apart tonight and clean it up, seeing as I have nothing to lose. But the shaft sure is turning freely by hand, I can easily pull the shaft out of the starter body, and it snaps right back in when I release it, so I'd be surprised if I find a lot of gunk inside, especially since it's relatively new, but it's worth a look.

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[flash]

just because it's new does not mean it's better. new parts fail A LOT (especially rebuilt ones). new and rebuilt starters are well known for failing. i bought a rebuilt one a few years ago that was dead right out of the box. i sent it back and bought a new one from porsche.



you have to bench test the unit to know what it is really doing. you can't just fiddle with it and see anything. be careful though, as that thing has a lot of torque (assuming it's working properly)

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[Cloud9...68]

Agreed. I suspect it's dead, given the fact that there's voltage going to it, the shaft appears to be extending, and yet it's not turning. I'm just assuming it's probably not too dirty inside because it's seen so little use. I tried having it bench tested at Advance Auto, but their tester gave an error message, saying it's not possible to test this particular part number (no explanation as to why, though). But the guy at Advance Auto rightly cautioned me that a bench test isn't necessarily definitive (unless the starter doesn't turn), because it doesn't put the stater under load.

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[Cloud9...68]

OK, I did a bench test on the starter by securely placing into a vise and applying voltage to the appropriate leads. The shaft extends quickly and without any binding or resistance, but it doesn't turn a bit, which is exactly how it's behaving in the car.



So, I started taking it apart to see if I could see something obviously wrong with it. When I removed the rear plate, exposing the commutator and the magnetic brush assembly, at least one of the brushes was laying inside the body of the starter, outside of its mount piece. This could clearly be the cause of the starter not turning, but I don't know if the brush fell out on its own, or while I was pulling out the plate that the brush assemblies are attached to.



So, has anybody here ever rebuilt a starter? I ask because this brush assembly is one miserable contraption. The brush mounts kind of rest in slots in the assembly without really being firmly attached, and of course there are springs that push the brushes toward the commutator which make it very difficult to keep the brushes in their mounts. So the whole thing is composed of over a dozen pieces which all sort of flop in the breeze, with springs trying to keep everything apart, and the whole thing is somehow supposed to fit inside the starter body, which is a very tight squeeze. I thought the seat switches were unnecessarily complicated, but this makes those look like a clothes pin. I can't for the life of me see how to put it back together. If anybody out there has ever done this, please let me know how you did it. My new starter is supposed to ship on Friday, so if I can't figure out how to put my old one back together, I'm going to forget about it and just put the new one in. Thanks.

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[MB968]

Never rebuilt the motor part of a starter, but I've had it done. There are still motor rebuild shops out there. You might take it to one of them. Other than replacing the brushes, it is a common part of the rebuild to take a skim cut on the copper bars that the brushes rub on. This allows the new brushes to wear-in/seat themselves with a newly machined surface. I would never just replace the brushes, assuming you can do that, without a good inspection of the armature including cleaning up the surface of the bars. Sometimes that cleanup is just to do a hand belt sand the surface of the copper bars if they are still in very good condition.,



I suspect you'll find it easier to put in the unit that comes on Fri.

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[Paul W]

I would imagine it looks something like this:







I wouldn't both trying to rebuild it....there is a good chance that it could fail again in the short term. Your solenoid is working correctly, but the armature/series field (the stationary windings are in series with the armature which is the rotating part) is an open circuit due to the brush not coming in contact with the commutator (part with copper pieces that the brushes ride on). You could either try to rebuild it yourself, or bring it to an electrical repair center, but that would most likely be half to two times the cost of a rebuilt unit.



Personally, I would put the new starter in and send the old one back for a core....if you are getting the new one local, don't they want the old one back? If you are not giving it back as the core, I would keep the solenoid assembly as a spare part for future use. I would chuck the rest. I paid something like $285 for my starter plus a core charge which I got back. Lucky for me, I got it the same day!



Here is the starter I replaced.

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[Cloud9...68]

The starter I ordered cost $136, including pilot bushing and free shipping, and comes with quite a guarantee - one year with three tows covered up to $50 each in the event it fails. So I figure the worst that can happen is that it craps out after a year, and I buy another one. As easy as they are to replace, it seems to be worth it.

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[Cloud9...68]

Installed the new starter last night - works like a champ. I managed to replace the bushing, too, using that seal bushing puller from Harbor Freight that Tamathumper recommended to me for the power steering rack seals



http://www.harborfreight.com/seal-puller-91352.html



I had to remove the bell housing window to allow the tool to grab the back of the bushing, but it came out without much trouble.

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[MB968]

Glad you got her fixed. The tool looks like a nice add to any toolkit.

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[MCL968]

Sounds to me like the contact plate in the solenoid is shot. This is the plate that connects the positive from the battery to the armature when the solenoid is engaged. Sounds like the solenoid is "working" just not completing the circuit.

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[MB968]

MCL, that was my guess too. Only time I really worked on one I found the plate to have suffered from a lot of arcing. The resulting oxide on the surface acting as a decent insulator, plus the pitting causing a loss in contact area. Be nice if we could just replace the solenoid as needed.

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