Hi I ex neighbor, good question "How to tell if coil needs a ballast?' here's the answer
If its a 6 volt tractor the coils LV primary resistance as measured between the two small terminals should be somewhere around 1+ to 2 ohms, many around 1.5 ohms, and IF SO NO BALLAST IS REQUIRED thats a coil for a 6 volt tractor AND YOU DONT NEED ANY EXTRA BALLAST on a 6 volt tractor.
If its on a 12 volt tractor, the TOTAL primary resistance (thats coil + any ballast) needs to be around 2.5 to 4 ohms THEREFORE
a) If the coil has ONLY 1 to 2 ohms resistance (like a 6 volt coil does) THEN IT NEEDS A BALLAST otherwise it will overheat
b) If the coil has 2.5 to 4 ohms resistance THEN NO BALLAST IS REQUIRED
Typical 6 volt coils are around 1+ to 2 ohms (many 1.5) while typical 12 volt coils are more like 2.5 to 4 ohms (many 3). If you use a 6 volt coil on a 12 volt tractor THEN YOU NEED TO ADD BALLAST or else it will overheat.
To measure resistance place an ohm meter on the low ohms scale across the two small coil terminals thats NOT the big high voltage terminal tower
Upload one or more videos to your post. Photo and video filesizes should be less than 5MB. 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 - Timing Your Magneto Ignition Tractor - by Chris Pratt. If you have done major engine work or restored your tractor, chances are you removed the magneto and spark plug wires and eventually reached the point where you had to put it all back together and make it run. On our first cosmetic restoration, not having a manual, we carefully marked the wires, taped the magneto in the position it came off, and were careful not to turn the engine over while we had these components off. We thought we could get by with this since the engine ran perfectly and would not need any internal work. After the cleanup and painting was done, we began reassembly and finally came to t
... [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.
