I have this goofy "Defender" key mechanism on my coilbox, I suspect this is an aftermarket theft prevention device? Has anyone had experience with them?

Not sure if I should keep or remove it?

Thanks,Jim

Yes, it's an aftermarket switch. I have an earlier version on my '15 T. Works great.

Does the gray colored area just outside the key turn as well? Mine rotates.

Thanks,
Jim

If it is in good working order? Use it! A few era correct accessories add additional interest to most model Ts. Just, don't lose that key (make a couple duplicates at least). I have two of those type key-locks (one earlier type, one very similar to yours. One has a key, but has a broken connecting tab that is not easy to make or repair. The other is intact, and should function okay. But it is missing the key, and so far, I haven't found a locksmith willing and able to supply a key for it (apparently, that one has a really obsolete tumbler and key blank). Frankly, I haven't tried all that hard to fix either of them as I have way too many other things I can't get to, and they just aren't a high priority at this time.
A working one in good condition? Enjoy!

If you stop to think about it for a minute, a T IS an anti-theft device in today's world.

1. Obvious to even the most casual observer that it's not a run of the mill bar-of-soap type car. "Be on the lookout for a black old car".

2. Pretty slow. Hard to make a fast escape.

3. Average thief couldn't start it.

4. Even if he got it started, he probably couldn't drive it.

great points Dick! especially #s 2,3, and 4!!

Before I decide to keep or remove, can anyone say if the original '15 switch is normal underneath or did this accessory change the stock parts when added on top?

Dunno about this particular brand James, but others I've seen of the type use the original "guts". The stock cover would be removed in the ones I've seen.

It's very interesting to learn how quickly horse thieves became car thieves. A book I've seen which is a collection of turn of the century wanted posters and law enforcement bulletins catalogs a number of offenders whose rap sheets included rustling and horse thieving within months of becoming . . . car thieves !

The factory switch on the coil box, operated by a universal "key" sure didn't offer much security. I guess for the most part, in those early days car theft was a rare occurrence.
.

James, I think it's a really cool anti-theft device and I think you're lucky to have it. :-)

(Message edited by Duey_C on November 20, 2017)

The problem is, there were several manufacturers, and numerous production runs. And all were not necessarily the same.
One of the nicest early ones I have seen looks a lot like the standard T ignition switch for 1913/'17. A nice Bakelite base with innerds similar to the earlier Ford standard switch. But all just different enough that only the most minor pieces (like screws for connecting the wires) will interchange. The base, the sliding switch, cover and key are all different. The one I have worked with is a KW, just like the coils, and probably was made and sold for use on Ford cars soon after Ford switched to the standard coil design in mid '13. This particular unit cannot have a simple cover change and work. The entire switch has to be changed.
Most of the later units, look more like what you have. Many of them, do mount over the standard Ford switch (which I think began about late 1917?), replacing the entire pressed steel cover (sometimes referred to as a "blister" cover). These switches can actually be used with no cover over them. A trick one would use if some scalawag swiped the key out of your parked model T (remove cover, twist switch with fingers, and drive on your merry way).
However, removing these anti-theft covers is not quite as simple as three small screws. Most of them (they do vary slightly), require turning the key one or both (one at a time) ways in order to remove the screws hidden by a shield inside the cover. The early one I am familiar with has the three screws out in the open. However, with it, the cover cannot be removed even with the screws removed unless the key is turned to one side (I forget which way?). For both the older and newer ones. No key? No remove cover.

I have seen a cover similar to yours that mounted over the earlier Bakelite base. But I did not have the opportunity to play with it and figure out its secrets. But it does tell me that yours could possibly be over either the older or newer type switch. It may or may not be a simple swap the covers. You will need to take it apart and look to see.

Another little secret to put away in some corner of your mind (it could come in really handy at some point if you happen to lose a key or something?). The later and electric equipped model Ts with dash mounted switches are much easier to hot wire than the early ones with the coil box mounted switch. The later ones can be hot wired with a simple move of a wire on the terminal block. Or a short jumper from a hot source directly onto the coil box power post. The later ones power directly from the post to the coils. The earlier style however have two power posts. Neither one goes directly to the coils. If you have the standard Ford key, and lose it? You can remove the cover, and work the switch with your fingers. With these anti-theft covers? Lose the key? Again, you cannot remove the cover. However, don't panic. It takes a slightly longer (couple feet) jumper wire. Make sure the insulation is in very good condition so as to not cause a short to the coil box metal. Remove the coils, all of them is easiest because you will need some room to work down there. Trim back the end of your jumper wire, and wrap it around one of the contacts at the bottom of the coil box. The contact buss will connect to the rest of the coils. Put all four coils back in, carefully placing the jumper wire back and up the back of the coil box (front could also work?) between the two nearest coils (a bit of corner gap helps the fit). Fairly small wire is easier, larger wire (like I usually carry a piece like is used for headlamps) can be difficult to force fit.
To run, the other end of the jumper needs to connect to power, battery or magneto, your choice, BUT DO NOT CROSS CONNECT TO BOTH as doing so will be bad for your magneto. This trick bypasses the switch entirely.
I actually did this for a club member on a tour once, many years ago, after his switch broke internally where it connected to the power buss. I also gave him a simple "twist connect" in easy reach so he could shut the engine off by simply disconnecting the two jumper wires. Then twist back together to go again. He completed the tour, and got home just fine.

A coil box key seems kind of useless for theft protection when you can hotwire a T with what, about fourteen inches of wire?

Wayne,

This is the K-W Auto Lock switch I have on the '14. It might be what you are talking about. It doesn't appear to be the same as the one posted but similar idea.



The innards aren't a regular switch (left picture). The lock cylinder has to be twisted to the right to line up the release internally (right picture).



It is the same switch K-W used on their Master Vibrator and has a Yale lock in it.



They work great and the key blanks are available at any lock shop.

Ken in Texas

I've got the base of that KW switch but not the cover. It had the KW switch knife also. I put a Ford cover on it and turned it on and off with a screwdriver for years then I got a Ford switch knife and stuck it in and put the cover on. I took the pin out of a repop key and it works ok. It's a 1914 coil box.

Ken P, That looks just like the early one I worked on! I did find a key blank I could modify, but nobody around here could figure out the cut for the key. I just had too much #### around here to deal with to pursue further. Maybe one of these days?
Thanks for the good pictures!

These have the same switch innards but the cover is stamped "Master Vibrator" instead of Autolock.



The Yale on the Autolock I have takes a Ilco TN3 blank.



The Yale on my Master Vibrator takes a Y220 but I don't have any idea why they are different.

There is a later all steel version of these coil box switches by K-W that fits over the switch. It looks more like the one James posted but I don't have a picture of one.

Ken in Texas

These were popular with the early Fords. Many different types offered.

James

Here is that Defender model, a later Model G, with strap over the box lid to keep thieves from stealing the coils!

I have a NOS Defender (complete) as Dan posted the ad above for - $75.00 mailed in the U.S.

Here are the internals of the switch I have. The base is different than the regular switch. It doesn't have the little barrel that the key pivots in. I just used a Ford switch knife. It doesn't turn smooth since the center pivot point isn't there but it works good enough. I thought I had modified the repop key but I didn't.

That's the "remains" of an original Ford composite switch - just missing a couple pieces !