Is it known when the early Heinze coil changes occurred?
They started with the 6 screw top plates in 1911.
Next they went to the 4 screw with the straight ratchet spring.
Next was the 4 screw with the angled ratchet spring.
Lastly the 4 screw with the angled ratchet spring but now the later points without the disc on them (used into 1913).
Anybody know about what months these changes took place?
You are correct with the progression of the coil design. My understanding is 6 screws and narrow-wide side for the groove for early 1911, then the 6 screw, then the four screw for 1912, then the different angle and points for 1913.
I don't know if it can be determined when the changes happened. Parts were used as they were available and nothing was wasted. Functionally, they are all the same.
What s/n or date are you trying to target?
My 1912 touring is S#112908 so it is about(??) a April of 1912 car. The body is the later slab side without door handles on the outside.
I have a set of the last style (used into 1913) coils but I believe the car is probably too early for those to be correct for it. If they are not correct, what style is the most likely to be correct for this car? 4 screw with angled ratchet spring or straight?
I have a set of modified later coils in it for touring but I would like to have a correct set for show.
Just curious, what do the two different 6 screw coils look like? Do you have a photo of the two side by side?
These coils were purchased from a outside vendor and not manufactured by Ford.
That being the case the only thing you will find in the Ford Archives are top level part number/assembly drawings with which the receiving inspection department could use to ensure they received what they ordered.
Contrast this with the KW "Williams" designed coil made by both Ford and KW. Hence you will find complete manufacturing drawings with documented record of changes which, somewhat cryptically, in many cases explain changes to the product.
I think you both mean 8 screws, not 6 screws. An April '12 car would most likely have used the 4 screw vibrator base, plain adjusting nut (no lettering, and a finer ratchet than earlier), and straight ratchet spring along with the 3 piece armature. (See first photo.)
In addition, the back side of the coil was stenciled in green-ish blue ink with a rather elongated upper case letter "I". (second photo--a little tough to see.)
It was right about April that Heinze came out with the later style vibrator bases that used the angled ratchet spring and re-positioned ratchet nut post, so it was about a month before these started appearing exclusively on the cars. For about another month, these continued to use the earlier assembled armature, then switched to the one piece style which was then used through the rest of Heinze production used on the Model T.
I'm working on a series of articles for the magazine that details and dates the many small changes in the early wood-box coils. I'm fortunate to have a professional photog who has been working with me, but she's getting married in about 6 weeks so her availability is limited. Hopefully over the summer things will settle down for her and I can get things finished up and off to the editor.
Thanks for the detailed information guys. Very helpful.
You are right R.V. We did mean 8 screw. My error.
Any photos or information on the two different 8 screw coils that Keith talked about. Didn't know there was two different types in 1911.
The "grooved-side" coils Keith mentioned are a patented feature that was actually a mortise and tenon joint designed to help keep the coil units together and reduce loss of primary contact due to the elimination of the contact spikes on the coil unit bottoms. This feature required that the coils have one side that is considerably thicker to accommodate the joint, and the result was that the 1911 Heinze coils came in pairs requiring adjacent coils to be installed with their thick sides together. These coils were stenciled "M" and "F" for "male" and "female". After awhile this joint was eliminated but the one thick side continued for some time, during which the stenciling changed to "L" and "R", presumably for Left and Right, then finally to "Y" and "Z", the meaning of which is unclear. Two pairs of 1911 coils are shown in the photo. Notice the mortise and tenon in the first pair, and how the coil side thickness was the same but without the joint in the second.
Actually, Tod, there were FIVE different style Heinze coils, exclusive of the stenciled letters, in 1911/very early '12. Keep an eye out for the whole story to show up in the magazine!
R.V. Thank you for taking the time to document and share your knowledge of Heinze coils.
Thanks R.V. for sharing. I did not know about the grooved side coils. Very interesting and I will be looking forward to your article.
Thank you for the talk about the Heinze coils.
I have a few other Heinze coils, I can't find much information about.
The coil with the Ford 1914 on fits in the standard Ford coil box. The other coil have two connections on the underside and one on the side. I was told it was for the Ford N 1906 but I am not sure about it.
Maybe you can clear this out.
The Model N used a coil with two spikes & one button connection, all on the bottom side. The button being the high tension lead to the spark plug.
Andre, the 1914 Heinze coil was made to fit the standard 1913-14 Ford coil box. The other coil was used on the 1908 Model S. The 1906 Ford Model N used a Splitdorf coil. Ford dropped Splitdorf at the end of calendar '06 and went exclusively with Heinze from then on until the end of the pre-T cars. Two different, or 3 different if you're picky about small details, Heinze units were used in '07 and '08.
Jerry, the coil you described was used on the '08 S and SR, with white glazed porcelain spark plug wire sleeves.
Now I know where all the coils went that I need.
Going from my 1907 N, using a Heinze box, (insulators as you describe), with that style coil. Not swearing it's correct however.