70 T&T ignition lock problems
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Heel & Toe
Joined: Oct 2008
Posts: 22
Likes: 0
From: Perry Michigan
70 T&T ignition lock problems
Help! I think I am an idiot!
I had been having some problems with my ignition switch on my 70 T&T car. It was real hard to turn the key to the lock position to get the key out and finally broke the cylinder. I finally got the lock cylinder out and installed a new one, but I can't get the key to turn to the lock postion to get the key out. Any help would be more than greatful as I am pulling my hair out. Please someone help me!!
Thanks Bob
I had been having some problems with my ignition switch on my 70 T&T car. It was real hard to turn the key to the lock position to get the key out and finally broke the cylinder. I finally got the lock cylinder out and installed a new one, but I can't get the key to turn to the lock postion to get the key out. Any help would be more than greatful as I am pulling my hair out. Please someone help me!!
Thanks Bob
Le Mans Master
Joined: Jul 2000
Posts: 6,001
Likes: 112
From: Saginaw Michigan
STRG COLUMN/TRANSMISSION INTERLOCK
There is a fairly common error concerning the ignition lock cylinder and the ignition switch on the 1969 through 1982 GM locking steering columns. When you rotate your ignition key you will find that there are actually 5 positions not 4. The positions (from full CW) are:
START, RUN, OFF, OFF-LOCK, and ACCESSORY.
On 1969 through 1976 Corvettes, you can always turn your engine OFF. However, you cannot get to the OFF-LOCK position (which locks the steering wheel and shifter and allows you to remove your ignition key) only if your automatic transmission is in PARK or your manual transmission is in REVERSE.
There is a lever on the end of your steering column (out under the hood directly below the brake booster). If you have a shifter on the steering column, that lever transmits your shift lever motion down to the transmission. If you have a floor shifter, there is a cable or a linkage system coming from your transmission that is connected to that lever. When you shift into PARK or REVERSE you will note that the lever moves to a full UP position (about the 2 o’clock position as viewed looking down the steering column from the driver seat.) With the lever UP there is a gate that is opened inside the column that now allows your ignition key to rotate further from the OFF to the OFF-LOCK position. This was called the Steering Column/Transmission Shift Interlock System.
In 1977 GM moved away from the expensive interlock system and the system was simplified on the Corvette. They went to a small lever on the steering column that was located right behind the ignition lock cylinder. You had to trip the lever with your finger at the same time as you rotated your ignition key in order to go from OFF to OFF-LOCK. So from 1977 onward, you still could lock your steering wheel but you could no longer lock your shifter.
Jim
There is a fairly common error concerning the ignition lock cylinder and the ignition switch on the 1969 through 1982 GM locking steering columns. When you rotate your ignition key you will find that there are actually 5 positions not 4. The positions (from full CW) are:
START, RUN, OFF, OFF-LOCK, and ACCESSORY.
On 1969 through 1976 Corvettes, you can always turn your engine OFF. However, you cannot get to the OFF-LOCK position (which locks the steering wheel and shifter and allows you to remove your ignition key) only if your automatic transmission is in PARK or your manual transmission is in REVERSE.
There is a lever on the end of your steering column (out under the hood directly below the brake booster). If you have a shifter on the steering column, that lever transmits your shift lever motion down to the transmission. If you have a floor shifter, there is a cable or a linkage system coming from your transmission that is connected to that lever. When you shift into PARK or REVERSE you will note that the lever moves to a full UP position (about the 2 o’clock position as viewed looking down the steering column from the driver seat.) With the lever UP there is a gate that is opened inside the column that now allows your ignition key to rotate further from the OFF to the OFF-LOCK position. This was called the Steering Column/Transmission Shift Interlock System.
In 1977 GM moved away from the expensive interlock system and the system was simplified on the Corvette. They went to a small lever on the steering column that was located right behind the ignition lock cylinder. You had to trip the lever with your finger at the same time as you rotated your ignition key in order to go from OFF to OFF-LOCK. So from 1977 onward, you still could lock your steering wheel but you could no longer lock your shifter.
Jim
