'71 Starter Troubleshoot

[tswaney]

I have been struggling with a no start issue for several months. I get a solid click from the starter when turning the key and often on the second or third try, it would operate. Battery checks out fine (Optima red top) and I have cleaned the terminals, battery ground, connections at starter, and transmission ground strap.

Occasionally, whacking it with a hammer has resulted in success, but I've tired of that so I pulled it out on Wednesday.

Bench test from a battery gave what appeared to be fairly good operation, until I realized the pinion gear apparatus was not resetting all the way back into the body when I cut the power. It hangs up about 3/4" from fully retracting. But I can easily push it all the way in and get a magnetic feeling click.

Suggestions? Does this sound like purely a solenoid problem? Replace entire starter problem? Yellow wire (terminal 50) problem?

[911pcars]

Assuming the starting circuit is getting what it needs from the battery and associated wiring, the click you hear is the solenoid completing the battery to the starter motor circuit via the mating of two copper disks (or equivalent) - that's normal. However, something in this circuit is creating enough electrical resistance to prevent the motor from rotating. On occassion, there might even be physical interference between the rotating armature and the field coils, but this usually happens during a hot start when the parts have grown dimensionally due to rising temperatures.

More typically, it could be worn brushes, bad contact with the commutator or grounded armature windings. Since you have it out already, you could DIY an inspection and/or cleanup/rebuild yourself or take it to an automotive electric shop for a test/rebuild or merely exchange it for a rebuilt unit. Depends on your preferred level of involvement.

Some folks prefer the lightweight starter motor as a replacement. Costs vary according to the source.

Hope this helps,
Sherwood
http://members.rennlist.org/911pcars

[Goth]

If funds are tight & since you already have it out. Try taking the solenoid apart and cleaning up the slide. Then put a little light grease on the slide. Once you take it apart, you'll know what I mean.

Good Luck!

[tswaney]

Thanks Sherwood and Doug. Does the fact that the pinion shaft assembly does not return fully into the starter housing (on my bench tests) indicate anything in particular?

I will try your advice Doug, and see if that "loosens" things up a bit.

[Zeke]

Good info from Sherwood, as always. However, I think your problem is only the solenoid mechanism in that you were successful in dislodging it with a hammer. Yes, it should retract as far as it is physically possible on its own. Can't hurt to try and clean it up before throwing in the towel and biting down on a new one

[tswaney]

Thanks to you too, Milt.

I may just dig in and see what's going on inside.

[T77911S]

u can also take the solenoid apart, rotate the contacts 180* and get new life out of it ( clean them also). the contacts burn and prevent current flow to the starter motor. also, check all cable connections and clean, especially grounds! i use to do electrical work on cars for a living and that was a very common problem.

[Gasman59]

Sticking Solenoid.

I had the same problem years ago in a BMW 2002. Since the starter was right there in the engine compartment, I amused many gas station attendants by popping the hood and giving the solenoid a rap with a hammer.

I finally replaced the unit.

Ron
70 911 E Targa