[fleetsidelarry]

I have a cadillac tilt/telescoping column of unknown vintage which I just put in my '48. It will not allow the key to turn to start in any position except park, not even in neutral. I had replaced the faulty cad key cylinder with one from the previous GM tilt column that was in the car when I bought it. When I first did this, the switch would turn to start in park and in drive (!). after more careful reassembly it now does not start in drive, which is good. it still does not start (key does not turn to start) in neutral. What I assumed was a neutral safety switch at the base of the column actually is not.

Is it correct for the column to allow start ONLY in park, or should it be letting me start in neutral also?

[LATECH]

does this column have the key in the side for a locking wheel?
There is a rack gear that slides the rod for the ignition switch. It will clear a pair of notches in the shift collar specifically cut to allow the key to be turned to the start posistion in park and nuetral.You need to look at the collar with the wheel off and the turn switch out of the way and you will see the collar is stepped and so is the rack piece. If the collar is not aligned properly it wont allow you to turn the key to start in the nuetral posistion.
The switch at the bottom of the column probably is the nuetral switch and the backup light switch. Depending on the vintage it may have a hi lo beam switch on the column,activated by pulling the turn lever back towards the operator.

[joe_padavano]

A little clarification. First, it is important that we know what year your column is from. From 1969 to the late 1970s, GM columns only used an electric neutral safety switch at the base of the column. The linkage to the trans (either from the column shifter or from the backdrive linkage on floor shifters) would rotate a collar in the column and make contact with the switch. There are two adjustments to be made on this type of column - you can adjust the switch on the column and you can adjust the backdrive link from the column to the trans.

Starting in the late 1970s, GM starter circuits did away with the electric NSS and incorporated a mechanical blocking linkage inside the column. This latter design prevents the key from being turned to the START position unless the shifter is in neutral or park. Again, the linkage to the trans needs to be adjusted for this to work properly. There is a switch at the base of these columns also, but it is used for the backup lights and to signal the ECU that the car is in park or neutral for the purpose of controlling the idle speed. This switch is NOT connected to the starting circuit on these cars.

Since we don't know which column you have or how you've connected the backdrive linkage or the switch, we'll need more info to help.

[fleetsidelarry]

latech, thanks for the quick reply. yes this column has the locking wheel, the headlight flasher is on the left side of the column about half way down, activated by a rod moved by the turn signal switch





sounds like I need to pull it apart again and try to figure out how to index the key switch to the mechanism you're talking about.

[fleetsidelarry]

Joe, thanks, I didn't see your post 'til I posted my reply to latech. Unfortunately, I bought the column from a friend who bought it at a swap meet, neither of us knows its origin, year-model wise.

When I bought the '48 it had a similar tilt column, but with no telescoping feature. It is my belief that the PO took the engine/transmission/rear end out of a late 70's model Camaro. The car also has the wiring harness from a later vehicle and I assume the harness probably came from the same donor.

This harness routes the purple wires from the ignition switch directly to the firewall connector block with no apparent detour through a NS switch

[fleetsidelarry]

as an update. First of all, I guess I put this in the wrong forum since its turning out to be a mechanical issue.

The problem appears to be in the geometry of the linkage between the column and the transmission. if I set the transmission in neutral and the column in neutral and adjust the rod to fit, the column won't go back into park. it turns out the PO fabricated a too-short transmission lever apparently without thinking of maintaining proper shift-rod travel. I can't find a stock lever in my garage even though I have 2 spare trannys, if my friend (who also has a couple of spare transmissions) doesn't have one, it should be pretty easy to make.

Thanks again for the replies guys, they got my thinking going in the right direction.