Ask me about tuning coils with the ECCT.


Model T Coils.com Service Map


31 States and 3 countries served to date ...

- Thank you for the support - 

Bad Windings / Open Secondaries


Winding Replacement

When we encounter a dead coil with bad secondary windings we usually just set it aside and choose a different one to rebuild. There are still plenty of good cores available. However, we sometimes have dead coils that are special in some way. Maybe they came with the car. Maybe they have sentimental value. Maybe they are later coils that were custom made to fit your early coil box. Maybe they're just a nice set of metal tops that you don't want to break up.

Replacing windings can be tricky business, but I will do so upon special request. *Note; I am referring to post-1913 coils only. I will not work on the early boxes. You must provide good donor coils AND the boxes you want saved must be in good condition. The price to "transplant" primary/secondary windings will depend on the time involved. Each transplant will be evaluated individually so we can come up with a fair price we both agree on. Contact me to discuss. erik@modeltcoils.com

Old Coils / History

Do you have any old coils sitting around?

Check your shelves! I will consider buying them from you, depending on their condition. Customers sometimes do this to offset the costs of rebuilding their good sets. 

Here's a general idea of what I will pay for old coils (and a brief coil history lesson). The prices are shown as untested / tested and rebuildable; *if there are no points/hardware on the coils, the price will be slightly less. Overall condition is also a determining factor.

1913 - 1915 6-screw brass top coils - $10/$20

1916 - 1917 4-screw brass top coils - $10/$20

1916 - 1918 black fiber-cased coils (I'm not interested in these but wanted to include them in the timeline for the coil history)

1917 - 1919 wood top coils with NO manufacture markings on the boxes - $5/$10

1919 - 1923 wood top coils with the "Ford" script burned in the side of the box - $5/$10

1920 - 1922 "Tractor Unit" coils were made with larger capacitors, heavy duty points, and tar with a higher flash point, can be used on cars too - $5/$10

1923 - 1927 wood top coils with the "Ford" script stamped on the upper edge of the box - $5/$12

*Aftermarket Genuine-stamped KW coils - $5/$15



Spools / History

Brass Spool Spacer, 1909 - 1914

Brass Spool Spacer, 1909 - 1914

Approximate dates of manufacture ...

Brass Spool Spacer, 1914 - 1917


Steel Spool Spacer, 1917 - 1925


Aluminum Spool Spacer, 1925 - 1927


Some Details


I use new KW points. They are made well, but still require inspection/adjustment/cleaning prior to installation. The upper cushion spring will be set to a standard gap, and the contacts will be set flush.

If you'd like to save money and use your old points, I'm happy to inspect them and let you know if it will be possible. However, sometimes old points cannot be salvaged. (And, I can't offer a warranty with used points.)  With full rebuilds, it doesn't make much sense to use old points in poor condition. They would be a weak link in the chain. 

Point gaps are set at .030" as a baseline. However, this is not a critical measurement and can change slightly during the tuning process. 


Using the correct capacitor is crucial in rebuilding the Model T ignition coil. I only use the ones supplied by certain Model T parts suppliers (Langs, Fun Projects, & others). They have the proper dV/dT rating and I will not use any other.

When installing new capacitors I always make good, solid mechanical wire connections prior to soldering. This, combined with fresh tar, will help keep the internal wire connections tight and operational for years to come.


Most of the time, the existing hardware is perfectly fine to reuse. I will remove any corrosion, lightly clean them, and always clean the top posts for good conductivity and appearance. I also install new fiber washers below the upper point bridge.

If you'd prefer all new BRASS hardware, that's perfectly fine, but it will add to the cost of your service by about $6.50 per coil.


Because the modern capacitors are thin enough to fit between the original glass insulator and the side wall of the coil box, I leave the glass insulators in place whenever possible.  

Oftentimes the wood panels near the capacitors have become loose over time. If this is the case I will re-glue the joints and press fit them for a secure bond.

Wood Conditioning / Wood Finishing

I have two options here;

  1. Leave your coils pretty much as-is, no conditioning or finishing whatsoever. Au Naturel!
  2. Clean the wood and treat with boiled linseed oil. This rehydrates the wood, brings out the color of the wood, and leaves a nice, flat appearance. Paint the tops black (w/ non-conductive paint).

*See the pictures below


The tar inside a Model T ignition coil serves more than one purpose. It keeps things in place and lessens the effect of vibration. It also protects the internals from moisture and corrosion. Therefore, I re-pot all of my coils with tar - just like Henry did. It is a bit time consuming (and sometimes messy) but I believe it is a critical step in coil rebuilding.




The Hand Cranked Coil Tester (HCCT) is a wonderful device created during the Model T era. There were many different brands and configurations, but they were all similar in operation. **The HCCT in the picture above is made by the Allen company and is my personal unit that I restored. Click here for pics and info on the restoration.

It uses an actual Ford Model T flywheel and magneto ring. But, instead of an engine spinning it around, you grab the handle and turn it by hand. It was much more precise than the "buzz boxes" of the day, and is in fact still used successfully today. The downside? They are heavy, non-portable, hard to find, and kind of expensive. 

Click here to view pictures of My Allen HCCT Restoration Project

Other "period" Testers


Devices like the one above were a definite step up from the simple buzz box, and can be quite fun to play with! This Servwell is another one of my personal treasures. It tests coil current amperage, spark plug function, demonstrates the actual electric current as it arcs between two prongs (don't touch!), and also tests light bulbs - single and double filament. 

Is it cool? Absolutely! Is it a good way to tune coils? Not really. It's just not very accurate. But, I admit you could certainly get your coils in the proper current range with it. And, that's exactly what they did. Good enough was good enough. Technology was still in its infancy ...



Fast forward about 100 years and we have the Strobo-Spark! This 21st century creation is a fantastic machine and brings more precision to setting the current draw of the Model T coil. It essentially functions like a HCCT but has the advantage of being portable. It is small, lightweight, and conveniently plugs into your a/c outlet.

 It tests for capacitor health and function, displays actual sparks in the window (single, double, triple), and measures current draw amperage. It also operates at a simulated RPM of about 450 to better emulate real driving conditions. Folks have been successfully using these machines for years now. Visit Fun Projects.com for more information on the Strobo-Spark.



"Dwell Time to Fire - The time required for the coil to build up current sufficient to pull open the points causing the spark plug to fire a spark." 

This, rather than current draw, is how the ECCT tunes coils. It is a fundamental change from all previous coil testing devices, and is the brilliant creation of Mr. Mike Kossor.

Visit ModelTECCT.com for more information.

ECCT continued


From ModelTECCT.com; "Engine performance depends on ignition timing not coil current so ECCT coil adjustment is done by accurately  measuring coil dwell time to fire spark, not coil current.  Each coil can be precisely adjusted to fire a single hot spark with equal dwell time to fire.  This guarantees no double sparking and minimizes coil to coil (cylinder to cylinder) timing variation to achieve optimal engine performance. There simply is no reason to settle for approximate current based adjusting techniques today like the HCCT to adjust Model T coils."

* Device Summary *

For those that have a strong preference, I will tune your coils with either the ECCT or the Strobo-Spark/HCCT. However, my default device is the ECCT.

This decision was based strictly on first-hand-witness-coils-in-the-car-engine-performance. My set of Strobo-Spark-tuned coils made my T run well. No question. But, after tuning the same set on the ECCT, my T ran significantly better. It's as simple as that. I experienced more power and better acceleration in both low and high gear. The engine ran smoother and yielded a higher top speed. Friends and customers have reported similar experiences.

Because the methodology is different, traditionally current-tuned coils might not "look" good when diagnosed in the ECCT ... likewise, ECCT-tuned coils might not "look" good when diagnosed in the other devices. It's like comparing apples to watermelons. Don't bother with this. The only real test is to try them in your car. 

*No matter which device I use, I will stand behind my work. If you are unhappy with their performance, I will re-tune them on the other device at my cost.

General Pricing


Complete Rebuild (1 set of 4) $175 + $24 for shipping, $199 total

I will diagnose your coils, clean the wood, oil the wood, repair the boxes to the extent possible, paint the tops black with non-conductive paint, clean the contacts, clean the posts, dig out the old capacitors, solder in new capacitors, repot the boxes with hot tar, install new brads in the doors, install new KW points, tune the coils, and test them thoroughly on the bench before mailing. **PLEASE NOTE; I WILL NOT WORK ON THE AFTERMARKET BLACK PLASTIC-CASED COILS**

So ... complete rebuilds are $43.75 per coil ($175 for 1 set of 4). **The cores you send me must be rebuildable. If you don’t have good cores, I can sell you individual rebuilt coils for $80 - if I have them in stock. Also, if your coils don't have any top hardware that I can reuse, the total price will be $10 more.

Return shipping is $24 for 4-6 coils to the Continental US. (for any other destination or number of coils, ask me for a shipping quote.)


Diagnosing, Misc.

Just pay $24 for return shipping and I'll give you a complete diagnosis, FREE of CHARGE. 

*Not all rebuild jobs are the same. I will work with you depending on what you need, and we'll come up with a price that we both agree on.

And, when your finished coils arrive in the mail, take them straight from the box, put them in your car, and enjoy!


Hit and miss Engines

Some hit and miss engines run on magneto and some run on ignition coils. Some even run on Model T Ford ignition coils. I am now offering these coils for sale individually to the hit and miss community. The price is $80 for one completely rebuilt Model T coil plus + $16 for shipping, $99 total. I can install Fahnestock clips for running wires to the coil OR leave them off for the “drop in” coil box set up. Like my other coils, these are guaranteed for one year.

*Note; These sales will depend on my inventory at any given time. Also, I will not work on/rebuild any other style or manufacturers’ ignition coil. ONLY Model T Ford/KW coils. 

**If you have any questions or would like to place an order, use the contact email form at the bottom of this site OR call OR text - Erik @ 661*609*7693.

For Sale



You can order a custom-made complete set at any time and I will build them just for you. Of course this depends on my inventory at the time. Prices usually range from $210 to $275 depending on the style/condition of the boxes (metal tops will be more). Don't forget to add $23 for return shipping.

**Note; you will also need to send me good cores to exchange. If you do NOT have cores but would still like to purchase a set of coils, the price will be approx $20 more per coil.

About Me

I am a retired federal Air Traffic Controller. I worked for almost 29 years at a major facility in Southern California. It was a great job, but its pervasive stress tends to take a toll on the body and mind. I didn't think so when I was younger. : ) Anyway, it's time to ease the stress, cleanse the soul, and lighten the spirit! Now more than ever I am realizing that life is short, and I intend to make the most of it ... time to focus on things that make me happy. So, I will be devoting even more time to rebuilding coils while continuing to enjoy the Model T hobby.


*On a side note; my maternal grandfather actually worked for Henry Ford. He started around 1938-39 at Ford Farms, then quickly transitioned to the Ford Motor Company and found his home. He became a foreman (not sure what department), and ended up spending his entire career at the FMC. The rest of his life he refused to buy any automobile (or tractor) that was NOT a Ford. He was a cool guy with lots of back-porch-embellished, Ford-related stories. :) If only I could go back in time and visit with him again ... 

For those of you who have never attempted to rebuild a Model T ignition coil, let me tell you ... it can be tedious and sometimes frustrating work. The going rates for coil services these days seem pretty darned reasonable to me, given the amount of labor required. My advice is this; if you find somebody who knows what they are doing and is willing to rebuild your coils at a reasonable price, jump on it. Even if it's not me. They've got the equipment and the experience. Pay them. It is well worth it. For example; a $6,000 freshly rebuilt motor with all the goodies won't run worth a darn without a good set of coils. Invest in them. Spend another $150 - $300 to either have your set rebuilt or buy a set outright. They are a necessary piece to the puzzle.

Enjoy those Ts,

Erik Larson


My Fords

1919 Model T roadster pickup


If I had to pick my favorite T ... this might be it (although it's a close call with the 23). She's such a good runner and has a wonderfully aged look and feel. 

1923 Model T Touring


This was my first T, and my "learning" car. Unfortunately, the motor failed shortly after I bought it. Since then, the motor and trans have been completely rebuilt ... I installed a Scat counterweighted crank, along with other internal goodies. I've also had to repair just about every other part of this car. As a result, I owe much of my T knowledge to this car.

1924 Fordson Tractor Model F


This is a recent purchase. It found it locally and just couldn't pass it up. When I bought it the engine was stuck and nothing worked. But, with some hard work, I was able to get it back to driving condition. If you've never seen these old Fordsons, do yourself a favor and check them out. In my opinion, they are sort of the missing link between the Model T and the later Ford tractors. Pretty cool machines! **Note; it also runs on Model T ignition coils.

1927 Model TT One ton truck


This is a no-frills TT. She runs and drives like my other cars ... she just goes much, much slower with its worm-gear rear end. It has taller gears installed for driving and has a TT Ruckstell axle for low-gear use. 

I use this truck for actual work whenever I can. After all, that's what it was meant to do!

1947 Ford 2N Tractor


This is a great old tractor. She runs very well. I actually use it on my property to brush hog, scrape, pull, etc. I also found this one locally. I especially like it because it has never been modified. It still wears its natural grey and is still 6 volt. If you need to do any serious work with them, they lack a little in horsepower. However, she works very well for "normal" use. It starts up every time and is a pleasure to drive! Its name is "Lulabelle 2" in memory of my Grandfather.

Grandpa on his Ford 8N



Model T Related Links

MTFCA, The Model T Ford Club of America - "The world's largest Model T Ford Club"

    If you're an owner or enthusiast you need to frequent this site.

KMW Ford Antique Engine Service - Engine Rebuilding specialist, Ed Katzorke. "Serving the needs of the Model T or Model A owner."

    You will be happy you chose Katzorke!

Chaffin's Garage - Model T Ford Parts

     Quality parts, fast shipping, and knowledgable customer service.

Lang's Old Car Parts - Model T Ford Parts

    Quality parts, fast shipping, an easy-to-navigate online shopping experience, and knowledgable customer service.

Snyder's Antique Auto Parts - Vintage Ford Parts. Model A Ford parts and Model T parts. Welcome Antique Automobile Enthusiasts!

I-Timer - The ideal timer for the Model T.

ECCT - "The new standard for Model T coil testing"

     Don't be turned off by new technology. Mike takes coil tuning to the next level.

Mitch Taylor's web site - "For Model T owners & enthusiasts"

     Mitch continues to contribute to the hobby, and his web site is full of good information. Thanks Mitch!


Fun Projects - "Antique car parts for Ford Model T, Model A, V8 and Tractors"

     Quality parts, some of which you can't get anywhere else.

Orange County Model T Club - is a chapter of the Model T Ford Club of America. Founded in December 1958, Incorporated in California on April 29, 1960. The Club is dedicated to the restoration and preservation of the Model T Ford.

Long Beach Model T Club - Founded in Long Beach, California in October 1954, the Long Beach Model T Club is dedicated to preserving and maintaining Model T Ford vehicles of ancient age and historical value. The Club also serves as an accurate and technical source of information concerning such vehicles for the benefit of its members and the general public

Western Idaho Model T Club - "Our mission is to preserve and maintain the Model T Ford of ancient age and historical value for current and future generations to enjoy."

SmokeStak.com - Antique engine forums related to old iron collecting, restoring and showing hit and miss engines, vintage Diesel, steam engines, antique tractors, antique cars, antique motorcycles, old generators, pumps, industrial antiques and collectibles. 


Your ultimate on-line source for Fordson, International, Farmall, McCormick-Deering and IHC antique tractor parts.

*Use the contact form below if you'd like to add your site to this page.


Contact Me

Question or Service quote? I will respond in a timely manner.



Model T Coils.com


Erik, 661*609*7693 Please leave me a message if I don't pick up. I will return your call.