Chief31

I'm a new member on this forum and have been reading past threads regarding troubleshooting the horns on my '67 coupe. i know that the horns work and that the relay is working as it should. I believe I have isolated the problem to something in the steering column. I have removed the "upper horn contact", cleaned the contact areas and checkout for continuity and it seems fine. I believe the problem may have something to do with the plunger in the canceling cam that contacts the "leg" on the "upper horn contact". Any help would be appreciated.

Vetteman Jack

Moved to C1/C2 Corvettes for some assistance.

65GGvert

post some pictures

Nowhere Man

with the horn button and contact off the wheel if you take a screw driver from the plunger to the wheel does the horn blow?

Chief31

I'll get some pictures today and post them. A couple of other things - I grounded the relay on the steering column above the rag joint and the horn works. Also, I have the telescopic steering wheel. According to info I've found, there is supposed to be a "shim" under the "horn contact" but there isn't one on my car. I also have factory A/C which makes seeing/working under the dash a bit of a challenge.

Chief31

I'll try "connecting" the plunger to the wheel when I get to the shop and report back. I checked for continuity between the black wire connector at the relay and the plunger yesterday with negative results - not sure if I had the plunger depressed. Not sure how all this works. Thanks for your help.

watson

I have a similar issue issue with my 67, except that mine is intermittent. I get everything working fine and a few weeks later it fails again. In my case, the issue is in the turn signal switch.

65GGvert

Not trying to cause any issues here, but the horn wire doesn't pass through the turn signal switch. It only uses a tab on the side as a connection point. The switch itself does nothing electrically for the horn wire.

Chief31

Nowhere Man - grounding the plunger to the steering wheel hub does not blow the horns. I also checked to be sure the hub is a good ground and it is. So, can I assume the problem is somewhere between the plunger and the black wire that connects to the relay? Where do you recommend I look next?

Nowhere Man

If you ground out the black wire at the turn single switch connector and the horn blows Then the problem is from the canceling cam with the copper ring or plunger with the spring If you want to remove the steering wheel hub you can try and ground out the copper ring

Chief31

Nowhere Man - Thanks for the advice. Assuming you mean the "arched" connector at the bottom on the column under the dash, I am going to work from the other end because it is so difficult for me to see and work in that area because of the factory A/C ductwork - unless you know an easy way! I suspect the problem has to do with the plunger or it's contact via the canceling cam rather than a connection or broken wire problem - does that seem reasonable? the plunger is very "wobbly" - you have to carefully push straight to keep it from binding in its sleeve - is that normal? Also, the spring is not very strong - again, does that seem normal? I'll have to get a steering wheel puller somewhere today so I'll be back when I've taken those steps. Thanks for your help.

Nowhere Man

The springs are about as strong as what’s inside of a pen. Taking the lower ac duct is simple And yes I mean testing the black wire at the turn single switch connector half moon part. You need to isolate where the problem is.

Chief31

Thanks Nowhere Man. I'l work on those things this afternoon and will report back later today or tomorrow. I appreciate your help. I feel like I'm getting closer!

Nowhere Man

If you where close I could figure it out in minuets

Chief31

I wish you were here! I'd buy the beer to celebrate your success when you were finished! I move very slow and carefully when I'm in unchartered waters. I know it must be painful for guys like you to have to "watch" guys like me work. I'll get there and I appreciate your guidance.

belgiumbarry

David Gilmour - Wish You Were Here / Live at Pompeii 2016 - Bing video

sorry, couldn't resist....

Chief31

Music to work by - I like it!

Nowhere Man

not really we where not born knowing. I know all this after having to troubleshoot the same problems on my dads 67 columns and one of his being a ac car I know what a pain it can be

Chief31

Nowhere Man - I didn't disappear, just had to dig out from yet another winter storm and do a few other chores. I was back working on the Corvette today. In order to use the hub puller, I had to first carefully nurse the 5/16-24 threads in the hub back to health with a thread chaser. I'm never surprised to find the effects of "bad wrenching" on these 50 year old cars! Once I got the hub off, I found that the canceling cam had poor/no continuity between the brass ring and the plunger. Cleaning the brass ring helped a little, but simply rotating the plunger back and forth in an attempt to clean corrosion on the points of contact between the plunger, spring and brass ring dd the trick. I probably could have corrected the problem by simply doing the same thing right after I removed the upper horn contact! But, I now know that everything is in good shape. I have everything ready to go back together tomorrow and will report back after I hear those horns blow!