Is there still a key source for 1926 closed car door locks?
Are repro keys available, if you know the repro number?
Was more than one type of lock used that need more than one type of key?
If you pull the lock out you may find a key number on it. The 26 coupe and 27 Fordors used the same lock. Just inside the door by the latch will be a screw. Back the screw all the way out and pull the lock. It might be easier to replace the lock and key though.
Everything that Don said is correct, but I'll add: 1. naturally the ignition key is different from the door key 2. the outside door lock key cylinders were made and supplied by both Briggs and Stratton, Yale, and Crown. The B and S will only have B and S information on them. The Crown cylinder (which was also used in Model A production) had Ford in script on the key. If you have a B and S cylinder, even if the key goes into the cylinder, it may not turn as B and S cylinders were made from pot metal and very few have survived deterioration over the years.
I have a B & S cylinder out of the car.
It has the key code printed on the square extension.
The lock turns freely, when I pick it.
I have an early Ford style key cutter.
What I need is a B & S key or a cross reference to a newer repro.
Several companies made the Ford ignition lock and key.
Those keys were evidently all made to Ford specifications and they all interchanged.
I do not know if the door locks and keys interchange though.
As best I can remember, and I have a B&S, Yale, and Crown cylinder and keys), the keys will not interchange between cylinders.
Hurd keys also fit those locks, but not my lock.
Hurd went in business in 1919 and may have supplied some of those locks, as well as the keys.
A note from their website suggests they are still in business.
Hurd Lock and Manufacturing Company manufactures security products for the automotive and industrial applications. Its products include cam locks and cams, plate locks, bolt locks, display case locks, self adjusting latch locks, non-locking twist locks, tubular keyed locks, switch locks, garage door locks, push locks, latches, and mechanical fuel pumps. The company was founded in 1919 and is based in Greeneville, Tennessee. Hurd Lock and Manufacturing Company operates as a subsidiary of Avis Industrial Corporation.