starter won't disengage

[steve]

!990 Legend runs great but lately starter won't disengage. Have to use battery cutout to stop it. Any ideas? Have changed ignition switch.

[Mike Harry]

But it does retract when you use a cut off switch? Don't know about wiring on a legend exactly, but basically there should be a hot wire to the starter itself (large wire) and a wire to the solenoid. (Small wire from ignition key)

I'd pull starter and bench test. While on bench test power to terminals while someone is working the key.

This should tell you at what end your problem lies.

I'd venture to say the plunger is getting weak or stuck. Doesn't explain however why it does retract if you kill power in the fashion you explained. That's a new one on me.

[Mike Harry]

Of course if a 90 has a "brain" (computer) its already smarter than me and probly controls the ignition in some fashion.  If. That's the case you can still do bench test to see what side problem is on, but a brain could change everything.

[RonT]

Follow the above instructions, pull the starter & have tested, rust & crust will be the culprit. When I read the initial post I understood it as when the master battery switch is turned off it shuts everything down, engine included if I misunderstood then there could but unlikely be an ignition switch sticking.

[Midskier]

I have seen which really makes no sense but when the starter relay (ford) has low voltage it may stay engaged
the fix was replacement battery connections , the relay and starter were fine

Dan T