Another Horn Rod Problem

P

PaintShaker

Junior Member
So I went to install my new horn rod. I can't even come close to getting it started down the bore in the steering column. There's quite a buildup of rust in the bore. I'm not sure yet how far down the rust goes. I need to increase the ID by about .030 in. to get a few thousandths clearance for the rod. Is the bore the same diameter all the way down, or might there be a step? It's very hard to see. I may be able to clean up the bore for 2 or 3 inches by running a drill bit down there. A cruder approach would be a dowel wrapped in emery paper, but beyond that I'm out of ideas. I'm hoping the only solution isn't throwing out the part and starting over. I would appreciate any suggestions. Thanks.
 
Go to a sporting goods store and get a steel bore brush or three, as well as some bore solvent and a rifle length cleaning rod. Chuck it up in a drill if you have to. That should knock most of the crud loose.
 
Any restrictions I have encountered when attempting to install a new light switch rod occurred in the first few inches of the steering shaft. Running a long drill bit down the steering shaft as far as I could usually cleared the way.
If your light switch rod is an older repo from the 1970's, its diameter may be too thick. Lots of improperly made light switch rods came into this country in the 1970's and were sold by Rick's and J.C. Whitney type of folks, who were only after the buck and knowingly sold inferior crap parts. If this car came to you with this light switch rod uninstalled, maybe it's a Rick's Special. The rods being made in the USA today are excellent quality, so if you have a new USA-made rod, that's most likely not the reason it won't go into the steering shaft.
If your steering column is out of the car, try pushing the light switch rod up from the bottom of the steering column. If the problem lies in the first couple inches up top, you should be able to push the rod up that commensurately far before you run into the tight spot. That would be a relief because then you'd know 90% of the inner steering shaft is clear. It's just the top couple of inches that need to be opened up.
Marshall
 
as said above there are reproduction horn rod that don't even go down the hole.
if it is any wider than the original it will most likely bind in the shft.

i have taken new reproduction rods apart and installed original shafts on them but it is not for the faint of heart procedure.

i am sorry i don not have an original shaft here to measure for you.

if you are going to run a drill through it you can weld a smaller shaft onto the drill bit so it will go all the way through but go with caution as not to break the weld.
 
Another item I have used to clean up rust in a bored shaft was a "beehive type" sanding disk, I think harbour calls them "spiral cartridges". Never used one on a steering rod, but the idea is the same. I like the long gun cleaning rod idea, maybe a shotgun bore.
 
Good news. Problem solved. I used three drill bits, each 1/64 in. larger than the next. I was concerned about the drill bit binding, when under power, and causing more problems, so I opted to go manual. I lathered everything up with rust dissolver and, by hand, worked each bit through the obstructed area. The rust only went down about 3 1/2 in. I was surprised to find an old bushing stuck part way down. Getting that out made things go a lot faster. Everything went well and it didn't really take that long. The horn rod is a new reproduction and it fit very well.
I thank each of you who took the time to comment. You made what I thought was disaster turn out to be quite manageable and I appreciate that.
 
The steering shafts are choked down in size to get the taper for the steering wheel hub and then they are machined for the special woodruff key so they have exposed surfaces for corrosion to build in there. If made properly, the horn/light switch rod will fit close since it has to provide a ground for the horn function.

They originally had a thin copper hat shaped split bushing to aid in a secure fit and good electrical ground contact between the rod and the steering shaft ID right at the top of the shaft so that the ground contact would be reliable for the horn actuation. The bushing also allows the rod to stay solid with the switch action while the steering wheel is turned. You don't want the lights to come on when turning the wheel. The little thin split bushings are available from Model A parts suppliers. I use Dow Corning #4 silicone grease on that bushing so prevent corrosion allow smooth action. The link shows the bushing.

https://www.snydersantiqueauto.com/product.htm?pid=977938&cat=41748
 
The bushing would be ground only for the horn - otherwise a preventative against turning the light switch rod when steering the wheel.

The light switch assembly at the bottom is its own in-out for current. Ground for the headlights/tail light is the attachment to the frame.

Glad you reminded me about the bushing. I have two 7 tooth columns on my workbench right now.

Joe K
 
You must log in or register to reply here.
Back
Top