Did you change out the coil? If it still has the 6v coil, yes it needs the resistor.
This comes from the "Articles" section of this site under "12 Volt Conversion". Good article, good info!
"The total resistance of the coil plus any external resistor (if used) should be 2.7 to 3.3 ohms for a 12 volt system. This level of resistance will maintain the correct voltage and amperage in the ignition circuit. Coil resistance is measured between the plus (+) and minus (-) terminals.
Most original equipment 6 volt coils are about 1.2 ohms, while most original equipment 12 volt coils are about 1.5 ohms. In order to get to the 2.7 to 3.3 ohm requirement, a ballast resistor such as a Napa ICR13 (Approx. 1.8 ohm) can be added to these type coils. Another approach is to eliminate the ballast resistor altogether by using a replacement coil with 3.0 ohms of resistance. Two commonly available 3 ohm coils are the Napa IC14 and the Pertronix High Voltage 40511. "
So, several factors to consider.
Also, some voltage regulators are polarity sensitive. If your regulator is designed for negative ground, it will still work but may experience shorter life. If I were converting to 12 volt, I would also go to negative ground. With negative ground, you can one day convert to electronic ignition, and all modern electronics are designed around negative ground. The starter does not care.
Upload one or more videos to your post. Photo filesizes should be less than 300K and Videos, less than 2MB. Formats allowed are gif, jpg, png, ogg, mp4, mov, and avi. Be sure to use filenames without spaces or special characters, and filetypes of 3 digits lower case.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Old Time Threshing - by Anthony West. A lovely harvest evening late September 1947, I was a school boy, like all school boys I loved harvest time. The golden corn ripens well and early, the stoking, stacking,.... the drawing in with the tractors and trailers and a few buck rakes thrown in, and possibly a heavy horse. It would be a great day for the collies and the terrier dogs, rats and mice would be at the bottom of the stacks so the dogs, would have a busy time hunting and killing, all the corn was gathered and ricked in what we c
... [Read Article]
Latest Ad:
1964 I-H 140 tractor with cultivators and sidedresser. Starts and runs good. Asking 2650. CALL RON AT 502-319-1952
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
