About a year back I replaced my turn signal switch and it didn’t last long. First I noticed that it cancelled fine on the left turn but stopped cancelling for the right requiring me to manually cancel it which wasn’t good to do because I eventually broke the tiniest piece of its catch so that it wouldn’t hold.
One other thing I may have done wrong was to add a little silicon grease to the friction surfaces. Did that cause an issue ?
With it apart now I see that the left signal tang is closer to the steering shaft than the right. I’m referring to the small tang that the cancelling cam engages .
The cancelling cam connects fine with the left signal tang but when I swing it to connect to the right signal tang it sweeps under it.
I’m not sure if it’s a switch defect not lining up or if the cancelling cam is worn out. Eyeballing it, well it looks fine to me.
These things aren’t that cheap to keep breaking.



Tough to see but the tang for the left signal sits closer to the steering shaft when engaged that the right…

and this is the right signal engaged


The canceling cam is turned around for the pic… The two pawls on the top of the canceling cam look fine to my eye but are they worn out ??? I don’t know . These are about $40 which I don’t want to throw at the problem if I’m not sure.

 

Hello Lt. Mike,

On my 1968 C3 I had a horn button issue and that is when I learned that the 1968 was a two year only part for the turn-signal and Horn plate. My Horn button had a plastic rivet fail and I had to improvise a repair since the parts were not available at the time.
On your C3, I would consider replacing the entire turn signal switch you have if you can. It is so sad that the replacement parts are such junk anymore. It looks like the switch is worn too much to allow it to work properly. Be careful with the horn button actuator as it is fairly fragile and bends easily. While inside the turn signal switch I would also clean any contact surfaces you can see and touch to help the parts work their best. A #2 pencil's eraser works great on the copper or brass surfaces used in the 1968 C3. DeOxIt works great as well but costs more than a #2 pencil...

A lot of the Silicone greases are not electrically conductive so applying it to the "friction" area might be a good idea just be sure that you are not blocking the ground path. I would also make sure that the grease doesn't get on any important electrical circuits. I found a lot of dried up old (Grey-white color) grease inside my wiper switch area which I removed with tiny dental style tools and a Hot air gun to soften the grease up. Conductive grease like battery grease will give you the lubrication without the inhibiting the ground system. I keep both kinds of grease in my shop because they are both used on our C3's.

If you need me to I can remove my steering wheel and take a look at another 1968 Turn signal system and Horn button. I am pretty sure my switch is the original as it sure looks old like the rest of my 57 year old parts. Plastic tangs inside turn signal switches would seem to be a very bad idea. Plastic wears differently in different weather conditions, I would assume that COLD is the worst for plastic to bend repeatedly.

I just looked up the parts available for the 1968 Turn Signal switch and the parts for the 1968 C3 seem pretty sparse. This just means we have to be even more creative to keep these beautiful and unique 1968 Corvettes on the road where they belong!

Best regards,
Chris

 

Thanks Chris, I ended up ordering a new switch and cancelling cam. The cam might be unnecessary but I want to be sure. I’m going to make sure the cancelling feature works properly before I button it all up. On another forum I’ve been told that others had the issue with the tang not connecting with the cam and so it wasn’t cancelling. They heated the tang gently while bending it down and that fixed the issue. Hopefully that wont be necessary with the new parts .
In the meantime I’ve pulled the dash out to replace the speedometer and tach. The tach I have has a bad paint repair to its face and the one going in is perfect.
The speedometers odometer never worked so a new one with the speed-minder option is going in.
The center dash is ready to go back in having a new clock and volt meter installed.
I’ll also be repairing a crack in the steering wheel while it’s out.
It’s near the end of a long to-do list.

 

It sounds like you are on the way to a successful repair of the "Turn Signal Nightmare". That is always a great feeling after solving a tough issue that has been plaguing you for a while!

You are replacing the clock in your console as well? I have the "upgraded" quartz Clock without the spring and points and it works well. Why are you replacing the clock? After I replaced mine I felt I should have used a different gauge like Oil Temperature, the oil temperature is important with my engine so that would have been a much more useful gauge than a clock. After the issues with Fuel pressure it might be useful to monitor the fuel pressure to keep your engine working well with the three carburetors.

Having been a Motorcycle nut I have accumulated a bunch of small battery voltage displays. My motorcycle is an older 2 stroke and is a kick start only street motorcycle but has a small alternator which makes the battery voltage even more important to monitor. Some that are tiny 3(/4" in diameter with three digits) and allow me to see the voltage of the battery while the engine is running. It would not be hard to install a one of the tiny aftermarket gauges out of the way so the driver can see it but not the rest of the crowd. The Holley EFI system has alarms for high or low voltage on the main display, Home screen. If the voltage goes one way or the other, the gauge has a Green box that displays the normal battery voltage, a Yellow background for something that is out of wack, the box will turn Red if the voltage drops below the settings and you are risking problems. The main screen shows the battery voltage which makes adding another gauge redundant.

If I had my ultimate wish for a gadget, it would be to use an Engine Analyzer from a piston powered aircraft monitoring the 427 engine to keep it from destroying itself. The modern engine analyzers are nothing short of amazing. You can monitor the health of each cylinder in ways that GM never thought of. I wish they made them for automotive use and sold them for 1/2 the price of the aviation products.

For the first few miles after working on my engine I like to have a vacuum gauge attached to the engine which ensures that it is running smoothly and everything is working like it should.

 

I serviced the clock once giving it a light oiling but I did nothing with its points. I did get it working with much satisfaction but it quit again after a week. This one that goin in is a quartz unit. I already installed a Autometer Extreme fuel pressure gauge off the column with a remote sensor . I had it connected between the pump and carbs off a brass T. The FPG verified a fuel pump issue with it dropping lower and lower finally dropping to 3lbs at cruise. No doubt the pump was failing so I ordered a replacement for my engine from Zip. They sent a Carter pump that when installed immediately flooded my carb sending a cloud of fuel smoke across my front yard. The gauge showed its value once again as the pressure was over 9lbs ! I had this issue with a Carter pump on my Dodge years back and had read a lot of posts about replacement pumps putting out excessive pressure. Explains why everything built today have regulators in line.
Damn though, I took care with the fuel line and brass T I had installed, now it gets tossed to bend and flare new lines, fabricate a bracket to install a fuel pressure regulator. The pressure is now 6-1/2 lbs and the engine is happy again. Been cleaning up a lot of wiring issues as well. Still have more of those to do.
You can see I’ve been knocking out a lot of issues lately.

2 stroke motor cycle ? Wouldn’t be a Kawasaki triple by any chance ?
I’ve got a couple bikes but my street bike has a classic tag on it, ‘98 Honda Valkyrie. 6 carbs (6 pack ) 6 cylinders and 6 pipes. I’ll add a pic of that at the end…

Here’s a shot from behind the gauges showing a professionally done wire connection. Seemingly no end to this



Here’s a video showing the fuel pressure gauge I installed..
You’ll notice the pressure wavering up and down about a pound. My pump was failing when this video was taken but thats kinda normal unless you have a regulator installed. With the new pump and regulator set at 6-1/2 lbs the needle sits in that reading like a rock.


Here are shots of the pressure regulator installed…