DarkObsession

Yesterday I replaced the ignition cylinder on my 1985 Corvette and I thought I'd post about a few things I learned along the way. This write up isn't a how-to, but more just to point out spots where I got stuck. Hopefully it will help someone out some day. If I had known the basics of how the telescope feature worked it would have taken me way less than the 3 hours it did!

I've never done this kind of project before so I did what I normally do and searched for a Youtube video. I found this one and watched it. Seemed pretty straightforward so I went to work. It wasn't as easy as the video made it seem because that video didn't have the telescopic feature but it was all I could find. I've included a parts diagram below and will reference numbers as I go along.

The first thing I'll point out is that the way the telescopic feature locks is really important to this project going smoothly. You have to get it (part 41) to lock inside the overall assembly otherwise you'll never get the lock plate (part 2) and retaining clip (part 1) back on. I didn't know how it worked so it added probably an hour or more to me trying to get everything back together.

When you start your project pay attention to how the lock mechanism (not pictured in the diagram) works! Undoing the lever that you use to lock the wheel down in your everyday driving from the big screw that looks kind of like a star is something like the third step in the process. What this screw does is put a slight amount of pressure on a rod (part 40) and wedge (part 43) that is inside the overall assembly. This little bit of pressure is really important!

As I went along in the process I couldn't get the lock plate remover to put any pressure on the plate (part 2) to remove the clip (part 1). The lock plate remover tool you need to borrow screws onto the threaded rod (part 41) but when you go to tighten it down to release the pressure, part 41 telescopes out like it is designed to do. The problem is that with the clip (part 1) removed, the entire part 41 will come all the way out! I was able to slip the retaining clip (part 1) off by hand so I moved along into the process of changing the lock cylinder out.

After I got my cylinder replaced (I'll give a tip on that in a minute) I replaced the turn signal lever and switch assembly (part 6) and then got stuck trying to put the lock plate (part 2) back on. As much as I tried there was no way I could get enough pressure on the plate by hand. I started searching online and read suggestions to put a threaded rod into (part 41) to "lock" the telescopic feature into place. Because I didn't understand how the system worked I was kind of lost.

I figured I'd try what I read but couldn't find a bolt or threaded rod that matched the thread type inside part 41 in anything in my parts bin (remember part 41 is what the star screw you took off back in step 3 screws into). I improvised by cutting off a slightly smaller in diameter screw that ended up sticking out a little longer than the opening in part 41. What this piece I made was doing was putting pressure on part 40, which made the wedge (part 43) engage the rest of the column assembly and lock everything into place. The piece you make has to be long enough for the lock plate tool that you borrow to put pressure on part 40 when you tighten it down.

After I figured that out I was able to get it to telescope lock and put the plate on pretty easily! It just took me an extra hour or more to work through everything!



Parts diagram from the 1985 Corvette telescopic steering wheel

Okay, some other tips. When you get to the turn signal switch I couldn't get it out completely so I just moved it out of the way as much as I could. To get the lock cylinder out you have to remove a Torx bolt. The video I watched didn't really say much about this and I saw two silver Torx bolts so I tried both of them. Neither of those T30 size silver bolts were the right ones. There's a black T20 size screw that's not really easy to see. Just know it's kind of at the 2 o'clock position as you're looking at the steering column and is behind a white piece of plastic with two metal fingers (parts 12 and 13) that stick out. You'll have to put these back in after you replace the lock cylinder and they just kind of slide into a slot.

Another thing, mark the orientation of parts with a Sharpie as you remove them. The lock plate (part 2) can be installed at least two different ways, correctly and upside down. You'll know if it's in the right way if the smallest part of part 3 sticks through it at the top. Also, part one will slide down from the top if it's installed correctly. I figured that out after mine was all back together so now I have to go back and flip it soon.

One other thing that's really important too. The plastic parts in my car are over 30 years old and are not flexible at all. There was a piece called a Horn Contact Retainer (not pictured) I broke on my car that just completely fell apart when I went to remove it. That piece slips over the finished assembly of parts 1 and 2 and insulates the horn contacts from accidental metal contact. I don't know if it would have been possible to get that off without breaking it so you might want to go ahead and buy a new one if you're going to do this project. When I got everything back together my horn was constantly blowing. I'm not sure if it's because I broke this retainer or if it's because the lock plate (part 2) and horn contact (part 3) are upside down. Either way, I've got to open everything back up soon and flip the lock plate so I'll replace that plastic retainer then too.

Okay, I know that's about an encyclopedia's worth of stuff but hopefully it helps someone out some day. I didn't realize how the system works until I was 2 minutes from getting everything back together when I replaced that star shaped screw. Once I got there everything made sense. I really hope this write up is clear enough to let the next guy know how to lock everything up. I'm sure there will be parts that are confusing though so feel free to ask away. Sorry there aren't any pics, I was too busy trying to figure everything out to try any of that. Good luck!

brushmor

Thanks for this write up! My lock won't stay in ACC mode so this is on my TODO list.