1951 Starter

[Davidcamper]

Today my starter went kaput. I removed it and bench tested it and nothing. It appeared to be locked up so I took it apart and the armature is shot. I've never seen an armature fail in this manner. Normally they overheat and sling solder. See picture.

[The Tassie Devil(le)]

Could be from the Starter spinning too fast by not being released from the Ring Gear after the engine started?

Centrifugal Force will cause this sort of destruction.

Bruce.

[Davidcamper]

You may be on to something. I did in fact notice the ring gear was not in its proper return place and the lever looks worn out. Thanks for suggesting this.

[Davidcamper]

Is it possible the starter can still spin while the engines running because I heard something like a pop so I immediately killed the engine and after that it wouldn't turn over.

[The Tassie Devil(le)]

If all the stars are aligned, and the Solenoid is holding the Bendix to the Ring Gear, and the engine revs up, just imagine how fast the armature is going to spin being such a small gear, on a large flywheel.   Self-destruction would be imminent.

There is a lift motor in the Twin Towers museum that was spun way too fast as the lifts fell, that the windings are far worse than yours.   I could post a picture, but it is not Cadillac-related.

Bruce.

[Alan Harris CLC#1513]

Twice in my life I have had the experience of the starter remaining engaged after the engine fired up. Once was on a 1959 Buick and once on an almost new MGB. Both times the starter burned up internally. On the MG, the wiring feeding the starter melted. I suspect that that is what happened to you. Both times I had the starter rebuilt. On the MG I replaced the wires and all was well.

[Davidcamper]

Thanks for all the info. I'm replacing everything on this starter including all wiring and the 4 fields but also have a second one as a backup.

Thanks again

[Davidcamper]

So far I have discovered the shift lever has wear and the spring lever shaft is badly rusted causing the lever to be somewhat froze.

[Davidcamper]

Well I removed the 2 bushings. Both worn. Also found a new solenoid lever.

[Davidcamper]

Removed the field coils. Note that this starter has 4. I have NOS coming.
I will post pics putting this starter back together in hopes it helps someone else.

[Davidcamper]

Parts for 1951 starter:
Starter 1107969
Armature 1917855
Starter Drive SMP 83423 MT
Solenoid 1118148 D939
Field Coils 826281, 826282 (2 each)
Leather armature shaft washer 818265 (1 only)
Field screw 3/8-24 1970469 (4 total)
Starter lever 1915662

[Chopper1942]

Be sure to put a small amount of grease on the Bendix bushing and both armature bushings.  We used to use lithium white grease.

[Davidcamper]

Will do. Thank you.

[Davidcamper]

Slowly but surely

[fishnjim]

I also suspect the insulation was bad/brittle and either shorted or lost attachment and spun and contacted the stator.  There seems like some other places insulation is lost.  They dipped them in some sort of thick varnish back then.
An electric shop would totally rewind and remachine these, so I hope you're doing that/replacing parts.  I see part numbers, but not sure you can find some of them.

[Davidcamper]

Yes, I was able to secure NOS parts. The new armature will be re-varnished.

[Davidcamper]

New coils, screws and painted case.

[Davidcamper]

New old stock armature re-coated

[Davidcamper]

Added name plate

[35-709]

Nice work, oughta spin your engine like a top.