Can someone post a pic on how the 1916 magneto horn wire routes through the firewall from the channel under the steering column
Here is my horn wire - June 1916 car.
The bell end of the horn nestles in the arch of the firewall.
Tom is correct it goes under the dash.
Bottom line up front: From the discussion below the horn wire on the 1915-1916 cars did NOT run through a hole in the firewall. Instead the dash shield was cut at an angle and had room for the horn wire or the earlier bulb horn tube.
From John Reagan’s web site at: http://www.funprojects.com/pdf/CA3638.PDF he has the following:
Beginning 1/15/15 the part was redesigned with the left end of the part being clipped on an angle to allow the [Bulb] horn tube to pass through but also a slight notch was added along the top edge at the left
side to accommodate a magneto horn mounting bolt. This 1915-1916 model was the beginning of the magneto horn era. On 12/19/16 a radical new design for 1917 was drawn up ….
See: http://www.funprojects.com/products/3638E7.aspx for a better photo of the typical 1915-1916 dash shield that has the corner cut off. The photo below is from his site.
And from John Regan’s posting at: http://www.mtfca.com/discus/messages/80257/89982.html?1240853878 John states: “The horn wires on 15/16 passed through to the engine side of the dash at the triangular shaped hole created by the left end of the dash shield being lopped off. This would be just above the floor board at that point. There was no extra hole in the wood dash to pass the magneto horn wire through to the horn on the 1915/1916 cars.”
At: http://www.mtfca.com/discus/messages/331880/351580.html?1364630800 has the wiring diagram for cars equipped with the electric horn and push pull light switch. It also has photos of the wires on the 1917 Rip Van Winkle Ford. One wire goes from the mag post on the coil box to the horn terminal. The wire from the other horn terminal goes up the horn tube mounted below the steering column and when the horn button is pushed that completes the ground.
http://www.mtfca.com/discus/messages/80257/93504.html excellent discussion of how the electric horn on the 1915s that had them (most would have had bulb horns) through to the late 1917s that still had the horn button on top of the steering column and the push pull light switch to the right of the coil box.
Note there were different style magneto horns that were made by the various suppliers.
Hap l9l5 cut off
My 16 coupelet's horn wire routing is as described by Hap.