|
Farmall & IHC Tractors Discussion Board |
Re: Re: Re: Re: Re: Re: Farmall H Electrical System
[ View Follow Ups ] [ Post Followup ] [ Return to Forum ]
Posted by Andy Martin on September 26, 2000 at 20:32:05 from (38.31.74.106):
In Reply to: Re: Re: Re: Re: Re: Farmall H Electrical System posted by ltf in nc on September 26, 2000 at 19:31:03:
Yeah but, amperage and wattage of a motor are also based on the horsepower being consumed. I have to believe that the 12v setup will take more horsepower out of the starter than the 6v because the engine is turned faster. So the load does change, the requirements on the starter change. If you put fewer teeth on the bendix for the 12v case to turn the engine at the same speed as the 6v, then the amperage should be roughly half. If the torque required to keep the engine turning at cranking speed is independent of cranking speed, and the 12v supply turns the starter under load at twice the speed of a 6v source, then the wattage or horsepower would double for the 12v case: double the hp and double the voltage so the amperage remains the same. I can't see that the torque required to spin the engine twice as fast would be only half the torque required for the slower speed. As I said before, the bearing drag probably is relatively independent of speed, but the engine compression components (valves, rings) probably work better at higher speed, so the torque may go up. I think it takes no more than 50# pull on a 9.5 inch radius crank to turn over an H fast enough to start, and that is only 40 ft-lbs. If it takes you 1/4 second to pull up 1/4 turn (a good snap), you are cranking at 1 rev/sec. So your manual cranking hp is only 40/550=.073 hp. My recollection is that a strong man can put out 1/6 hp, and .073 is roughly 1/12, so it seems reasonable. 885ft-lbs/sec would equal 1,118 lbs pull on a 9.5 inch crank at 60 rpm (1/sec), or 280 lbs if you could spin it at 4 rev/sec. A strong man indeed. But both the man and the starter can start the engine. The man, however, is not in danger of moving the tractor if it is left in gear: the starter is much more powerful. For sure we agree that 12v is not bad for a 6v starter! And please don't take offense by my discussion, I guess it's my 4 cents worth
Follow Ups:
Home
| Forums
Today's Featured Article -
Talk of the Town: Winterizing Engines - To Drain or Not to Drain? - by Russ Berry. What is this strange attraction I have to equipment and machinery? How did I get this way? I came from the suburbs and own a small horse farm in rural Loudoun County, Virginia. You can call me a "weekend farmer." The local farmers do. Does it bother me? No. I am just happy to have their friendship. At least the word "farmer" is in my title. But what is the attraction? How can I explain the sensation and exhilaration I feel when I turn the key and hear the engine come to life (most
... [Read Article]
Latest Ad:
2022 John Deere 5045E, 4wd, front end loader and 3rd function with grapple. 120 hrs, 55k new, must sell
[More Ads]
Copyright © 1997-2024 Yesterday's Tractor Co.
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. Yesterday's Tractors - Antique Tractor HeadquartersWebsite Accessibility Policy |
|
