C3 Ignition Key lock

[Yves Thaens]

Hi,

As an intermezzo in the body prepping of my car I took a good look at my steering column (79) and took of the steering wheel and such. I was planning on changing the lock, since a previous owner had changed to different locks on the doors so now there are two different keys. It seems impossible to get at the lock cylinder. Can anyone discribe me the procedure please. I already checked my workshop manual but the photo's (copied types) and text are not really clear to me.

Thanks

Yves

[Robert S.]

Re: C3 Ignition Key lock

Yves, I am not certain about your 79 but I think it should be the same as my 78 (one owner) with two keys. The square one for the ignition and the round one for the door, glove box and spare tire lock.

Bob

[Peter L.]

Re: C3 Ignition Key lock

Yves/Bob - The 79 Corvette and all other 1979 GM automobiles and trucks made in the US and Canada have two types of lock cylinders with the "A" and "B" type keyway. All ignition lock cylinders have the "A" type keyway and all door, glove compartment, and rear compartment lock cylinders have the "B" type keyway. They don't call out the spare tire lock cylinder but from experience the 1979 Corvette spare tire lock also has the "B" type keyway.

The ignition lock key has the rectangular head and the head markings (GM logo and MARK OF EXCELLENCE on both sides of the key head). The key identification "A" is located on the shank just below the coining on the head; a code number is stamped on the knock-out portion of the key head and has indicia from any one of the seried 0A00 to 9A99 and 0B00 to 9B99. The numbers (also called the KEY NUMBER) identify the lock's combination and are used when ordering or making new keys by code.

The door, glove compartment, and rear compartment lock key has the oval head and the head markings (GM logo and MARK OF EXCELLENCE on both sides of the key head). The key identification "B" is located on the shank just below the coining on the head; a code number is stamped on the knock-out portion of the key head and has indicia from any one of the seried 0C00 to 9C99 and 0D00 to 9D99. The numbers identify the lock's combination and are used when ordering or making new keys by code.

Checking back through some information, the use of the separate key for the ignition switch lock (ignition lock cylinder different from the other locks) and another (separate) key for all door, glove compartment, and rear compartment locks (lock cylinders different from the ignition switch lock) began on GM passenger cars and trucks in 1974. Prior to 1974 (starting in 1967) there were two separate keys with different keyway lock cylinders but one key was for the ignition switch and door locks and the other key was for the glove compartment and rear compartment locks (and spare tirer lock on the Corvette).

Pete