Going with Champion Spark Plug numbers, the original standard plug was a D16. That was then changed to D15Y. The plug has about the same effective heat range because it is one heat range colder but with an extended tip plug. The plug for light duty was D18Y. After leaded gasoline was phased out Champion changed the recommendation to D15Y for heavy use, D18Y for standard duty, and D21 for light duty.
Because the D21 is a pretty hot plug it can causes problems if used for heavy duty use. It can cause preignition if it runs too hot.
I use D21s in my I2444 with good results but that engine (C-153) is rarely used at more that about 2/3 throttle and light load. On my Super C with a 6 foot Wood mower I run D18Ys because that engine runs under much more load.
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 - The Rescue of a Fordson F - by Anthony West. Introduction I live in the UK and have for many years restored Fordson tractors (in the main model N's). I have also restored and shown model F's, E 27N's, Field Marshall Series 2, David Brown Cropmasters and the old rey Fergeson T 20. At one time I had seven restored examples which were shown and used in ploughing matches. As most restorers, I have a number of war stories I can relate on a range of topics that may help other like minded and interested people. Perhaps my first p
... [Read Article]
Latest Ad:
Sell 1958 Hi-Altitude Massey Fergerson tractor, original condition. three point hitch pto engine, Runs well, photos available upon request
[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.