Light Switch Cam Frabrication?

Probably not a common problem (didn't see it in the search) but figured I'd ask around here in case someone has gone down this road before.

I'm looking at getting a replacement for the light switch cam (white plastic thing at the end of the light switch stalk, see pic) for my '90 TR fabricated. I just don't think that I'm going to have much luck in my gluing, and it does seem to take a bit of stress when it hits its stops, and for that thing that is supposed to kick the brights off when you turn the lights off.

Anyone done this, or any other repairs to this piece?

Saw a thread that talked a little about getting Boxer switches rebuilt (as a complete unit apparently), but not TR.
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No, that seems to be part of the actuator for the headlight itself, but thanks for looking! What I was looking for was at is part of "MAIN SWITCHING UNIT Part No. 121561" on the steering column, but probably didn't describe it that well.

I did try a bit of Fiat searching with no luck. BUT I think I accidentally might have stumbled on a lead that's probably already well known but just not well documented here. As soon as I can confirm that it's the right stuff I'll post it up for future reference.

 

Thanks to one of your previous posts I knew what I was in for with the rivets (and why is that the only one of the three that doesn't have easy access?).

Likely there's no way to get that part itself, but there might be a more economical unit to steal it from. I'm hoping to verify this in the the next couple weeks.

My gluing worked surprisingly well, but I glued to the stalk itself for strength. Previously the stalk wasn't rigidly attached and could slip a little to prevent over-torque, and I'm not sure if that's really how it was supposed to be. The most stress that part seems to get is from the section of the cam that's designed to prevent you from having the stalk in the brights position with the headlight off. Not sure why that's necessary, but if someone were trying to turn off the lights with the brights on, and really cranked on my glued part fighting to get it to turn, I'm not sure if it would just push the stalk up or would just break the cam again. Didn't push it that hard but seems like it would take a lot of toque to get it to lift up on its own. Not even sure if it was ever meant to work that way, because mine always self-limited way below that torque anyway.

I'll try to finish a CAD drawing of the part at some point that could be used to get it CNC'ed, but I think in the end if all my options fail I'd just machine it by hand on a mill/lathe. After all the time I've wasted, I kind of hoping it doesn't go that far; I broke the darned thing while I was trying to fix something else (which isn't even completely finished yet).
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Yeah, it did seem a little odd that it would slip, and that I should have to reset its position. But then again it's a Ferrari, so who knows? My stalk has two groups of two ridges at 180 deg, that look like they're supposed to grab onto the cam, but it was hard to imaging them doing a whole lot. There were light grooves in the cam to match them, but it looked like they weren't built into the cam but rather there from just pressing against the stalk for a while. Not so much that mine looked "worn" but more like it wasn't going to do much to begin with. Though there was likely an incipient crack forming that just made it not grip as well.

Shamile, if you were to have your headlights on with the high-beams on, then try to turn the stalk to turn the lights off what would happen? Would it just be too hard to turn the stalk, or would turning the stalk actually lift the stalk up to cancel the brights and allow the lights to be turned off? Previously mine would just spin in this situation, due to the "torque-limiter."

And I hate to think what Brian would say if he heard you saying there's no rev limiter...

 

So my glued light switch stalk seems to be working fine, but I went looking for alternative sources.

Below are pictures of a multi stalk unit which I am told goes to the 1979 and newer Lancia Coupe, Spider and HPE. Since I didn't source this directly through Lancia I don't have a P/N, sorry. The box on the new unit says it's from Ricambi Fiat, and that it's for a Lancia. I wasn't able to find something similar looking at the Fiat branded cars, which was the first place I started.

As seen in the picture the connectors are obviously not right. But from initial inspection all the functions and the unit itself are the same as on my 1990 TR. I didn't yet do a pin-by-pin check to see if TR connectors could just be grafted on, I didn't check that the mounting holes are in the precise same position, and I didn't check the diameter of the hole for the steering wheel. But visually this part looks like it is a dead-on match other than the connectors. (The round shape of the brush for the horn is actually just the temporary cover on the new part)

The key for me was stealing component parts, and in this case it does look like all switches, stalks, boards, etc. match up perfectly with the guts of the Ferrari unit. EXCEPT for the labeling. As can be seen in the closeup of the head of the stalk, it's labeled in English instead of just obscure hieroglyphics. Not sure if that it'd really care when compared to the cost of buying a much more expensive F-Part.

If anyone knows more about Lancias or knows a helpful parts shop, I'd love to find out more about part numbers, or better yet if there's a multi-language version that has the same symbology used on the Ferrari part.

I ended up with one "new" unit (looks like it's been tried out, but whatever) and two used ones for parts. Going to dissect one (pull the rivets) and pull out the light switch stalk as a back up. Just hoping I don't really need it. But maybe I'll learn a little more inspecting the interior.
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