The H4 mag impulse retards the timing by 35 degrees when starting, which if you have your mag static timed correctly, draws it back to TDC, or 0 advance. If the mag is in good shape, it'll fire no matter how fast the engine is spun by the starter. The impulse only activates below 150 RPM, above this, it is turning fast enough on its own to spark just fine, and the timing is advanced to 35 degrees BTDC. The retard function is only for hand crank purposes, to avoid a kick back and a possible broken arm or worse! Kick back has never been a problem when using a starter however. The engine will crank over and start using a 6 volt starter turned by a 12 volt battery even with the starting timing set to 45 degrees advance, because the starter is strong enough to turn the engine right on through any possible kick back it might try to do. The only symptom you "might" run into would be slow cranking due to too much initial static timing, the old familiar "wroo ... wroo .." situation, when the engine is already hot. The cure for this is to retard the static timing a little until it starts fine when hot too. It usually takes over 50 degrees initial advance to cause this issue when hot, but boy will she ever start easy like this when cold!
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 - Ford N-Series Transmission/Hydraulic Fluid - The Full Story - by Llamas. The transmission fluid in an “N”:-series tractor lubricates the transmission, differential, rear wheel bearings, PTO and hydraulic pump drive, and it also cats as the working fluid for the hydraulic lift. In 9N/2N models, it also lubricates the steering sector and shaft system. The owner’s manual for the 9N and 2N models specified the use of only two fluids. They were STRAIGHT MINERAL OIL SAE 90 (above freezing) and
... [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.
