78 SC Ignition Switch problems

[jhmol]

Did I tell you I was a slow learner? So... I put the switch alone in the circuit and turned the screwdriver. A great sound occurred. Engine fired right up. And I could repeat that with the screwdriver. So I took the switch out and put it back on the mechanical portion. The key worked once. Then not again for 10 tries. Then again. Then not again for 15 times. I took the mechanical part off and (now that I know what I'm looking for) got the electrical to work every time. So doctor, what is the diagnosis? I'm guessing that I could drive around with a screwdriver and a hole in the dash or get a new mechanical part. How does that work with the key? I'm guessing there is a way to pull the key cylinder... but I get ahead of myself... again.

[jhmol]

Okay... so with just the electrical switch and screwdriver I can turn the switch to start and it returns to run with a click... but then if I turn it slightly further counterclockwise I get another click. Don't know if that points again towards the electrical switch. I should be getting the new switch by the end of the week.

[ossiblue]

Originally Posted by jhmol

Did I tell you I was a slow learner? So... I put the switch alone in the circuit and turned the screwdriver. A great sound occurred. Engine fired right up. And I could repeat that with the screwdriver. So I took the switch out and put it back on the mechanical portion. The key worked once. Then not again for 10 tries. Then again. Then not again for 15 times. I took the mechanical part off and (now that I know what I'm looking for) got the electrical to work every time. So doctor, what is the diagnosis? I'm guessing that I could drive around with a screwdriver and a hole in the dash or get a new mechanical part. How does that work with the key? I'm guessing there is a way to pull the key cylinder... but I get ahead of myself... again.

Edit: You posted while I was typing. To be clear, you have resistance when you move to the "start" position and it springs back on its own. Correct?

A couple of possibilities but first, when you use the screwdriver, do you feel the spring resistance in the unit? Does it spring back after starting? If so, then let's take a look at the mechanical part.

First, as mentioned by RDM, make sure you are turning the key all the way to the "off" position after an attempted start to be sure the lock out is overridden. Next, use a pliers to see if the pin that fits into the electrical unit is solidly embedded into the lock. If it rocks or twists in the lock base, that may be the reason why it won't turn the electrical unit past the starting resistance.

If the pin checks out, observe how much of a twist the pin makes when you turn the key from lock to "on" to "start. You can do that by making a dot with a felt marker that lines up the ear of the pin with its location on the base. Then, use the key to turn the lock fully to the "start" position, and make another dot on the base where the ear is now located. Do this several times to confirm the pin is turning as far as it can and the lock out is overridden. Now, place the electrical unit next to the lock and line up the slot with the dot in the lock base when the ignition was "off." Twist the unit with the screwdriver and note where the slot is positioned in the "start" position. Does it match the second dot in the base or is it twisted further?

Try the above checks and report back. At this point, I'm a bit puzzled until I know the pin and electrical unit both turn to the same degree.

Your problem may be with the mechanical lock out which is in the key tumbler assembly. Take a look at this thread as it sounds very similar. Ignition switch springing problem

[jhmol]

With the electrical switch, there is spring resistance when I turn it to start and it returns to run.
With the mechanical switch, I am returning the key all the way to off... most of the time I'm removing the key.
The pin moves just a little with pliers... less than five degrees.
So I followed your instructions for the dot. See first photo.
The single dot is off. The two dots is start. And the three dots is run. It took me 30+ tries turning the key to get it turn to "start" (2 dots). It stops most of the time at "run" (3 dots).
I just tried another 30+ times and got it to "start". See second photo.

[jhmol]

Dru, I don't know if they are called the same thing... but there is a lock out on the electrical and another on the mechanical. LJ sent me a link to a thread that I followed to Ignition switch - inside to fix START lockout. This appears to describe my problem. If I can fix it, I will.

[ossiblue]

If you haven't read the thread I linked in my last post, please do as it sounds like your problem. The issue turned out to be the lock out which is in the mechanical/key/tumbler part of the lock--not the electrical unit. The thread shows how to repair the problem as well. Given that the pin doesn't turn completely to "start" consistently, I believe the lock out is the issue.

Here's the problem and the link. Ignition switch springing problem

[jhmol]

LJ... I was reading all of it and I think you've found the culprit. I don't plan to rekey the car... but I think I need to go into the mechanical part and clean things up a bit.
Late here. Another day. Thanks for all the help. I'll see RDM tomorrow at work. We'll have lots to talk about. Thanks.
John

[jhmol]

LJ, RDM, Progress. I disassembled the mechanical switch. Found everything in order (no broken parts, no excessive grime). Cleaned it all up and lubed with dry lube and reassembled. Got 3-4 times to start out of 20. Disassembled all and removed the pin. Got 20 out of 20 times to start (without lockout protection). Disassembled all and lubed only the bottom of the assembly and wiped all the lube off the ring so there is a little friction to help slide the ring back. Got 11 out of 20 times to start (with lockout protection). So... what do you think? I'm leaning towards removing the pin and spring and training myself to not turn the key to start while the engine is running.

[jhmol]

LJ, Thank you. I reassembled everything minus the pin and spring in the mechanical switch. All is good. Fires up EVERY TIME and gives me a bit more confidence that I won't get stuck some place. Time to get some drives in. Again, thank you.
JHM

[RDM]

Congratulations!

But did you say drive? Here's what you missed tonight:



It doesn't get much more drivier than that.

[myamoto1]

I just went through the ignition replacement today and using the same trick I learned from seat installation, it took me less than 10 minutes to reinstall the top screw on the ignition (yes the one up under the dash). Ok, so I started out with grand finale because while I did learn the super cool way to make this a super (relatively) easy job, it took me an hour and a half to figure out the trick on the front end. For those of you that have already removed/replaced your seats, you may have already guessed at the trick. For the rest, I'll pull a Tarantino move and start from the begining even though you already know the ending (or do you....).

I just needed to replace the igniton module, but I prepped to remove the whole unit if I needed to. Tip #1, get a 3/8" bit for your multi tool and cut a groove in the break-off bolts:




Next I drilled out the rivets and replaced the break-off bolts with stainless allen head bolts:


I didn't pull the whole unit, so I didn't remove the knee pad, but I was replacing my blinker and washer stalks, and noticed that with a stubby allen, you should be able to get to the retainer bolt:

[jhmol]

Nice pics Josh and Dru. Josh has the makings of "The other Bentley - The rest of the Story". Dru... you just like to rub it in. Thanks.
JHM

[myamoto1]

Ok - for the moment you've been waiting for, the easy button/tool:




That's from Harbor Freight (if you couldn't tell by the Pittsburg logo). I used a driver bit about 1 1/2" long and it worked like a charm. Even easier was the reinstall - just use some electrical tape to hold the screw. Once it "bites" pull out the bit with the tape and then continue to screw it in the rest of the way:




Also found out that the AA mini-mag fits perfectly in the corner between the vent hoses. You need to have your kick panels out for this trick:

[jhmol]

Josh... THAT is an OUTSTANDING hack. Very elegant and straight forward. Probably a bit more reproducible than mine. My solution for getting the allen bolt reinstalled was to balance it on the end of a bent croquet wicket with the other end stuck in my right ear and my two middle fingers gently trying rotate the bolt applying equal amounts of force to both sides to keep from losing its position. Oh, and I like your flashlight idea better too. I had a small light balanced on my chest under the dash. If I held my breath just right, the light lit up the bolt perfect.

[myamoto1]

The flashlight hack was almost by accident. I was trying to find a way to balance it and it just slid back, right into the perfect position. I still had to pull it out of there and either jam it up in between some wires on the left side (on floor facing up) of the ignition or try to hold it with my left hand. Just be forewarned, if you jam it up on the wires, it'll be great and awesome, until it falls out and wacks you on the forehead.

2 other comfort hacks I found were 1) a middle row seat from a Ford Expedition is the perfect height to lay on. If you had one of those adjustable height tables popular for engine removals, I'd use one of those to lay on. 2) a #4 soccer ball donated by the neighbor's kid works perfect as a head rest. It fits right in the curve of your neck, below your skull. Also, don't quote me on the #4 thing. I don't know soccer or soccer balls, but I do know hacks

[Hi_Fi_Guy]

Decided to tackle this project today and wanted to thank everyone who has contributed to this thread. Made a tough job easier.

My 1971 still had what I imagine is the original switch with slot-head screws. Made the top screw all the more challenging.

To pay this thread forward for anyone else with an older F-Body 911 featuring the slotted screw:

• The angle of the drive-bit must be perfectly square with the screw head and the the mini-ratchet won't work (at least wouldn't work for me with the slotted screw).
• A 1/4 in. open ended wrench will easily turn the driver-bit while you use the index-finger of your other hand to push the bit and maintain engagement with the slot-head screw.
• Unless maintaining a concours car, replace the slotted screw with a Phillips head or hex-head M4-.07 10 mm (mini-ratchet worked perfectly for this). Your future self, or the next owner will thank you!

[REVerend]

On my SC the steering column lock was hanging up slightly and contributing to some issues. Fortunately the metal is relatively soft and it was quite easy to drill through and install a roll pin making it permanently retracted.

Bonus is that it’s easier to push/manuever my car around in the garage if I don’t have the keys handy.