Yesterday's Tractor Co. Shop Now
   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
Classified Ads
Photo Ads
Tractor Parts

Discussion Forums
Project Journals
Tractor Town
Your Stories
Show & Pull Guide
Events Calendar
Hauling Schedule

Tractor Photos
Implement Photos
Vintage Photos
Help Identify
Parts & Pieces
Stuck & Troubled
Vintage Ads
Community Album
Photo Ad Archives

Research & Info
Tractor Registry
Tip of the Day
Safety Cartoons
Tractor Values
Serial Numbers
Tune-Up Guide
Paint Codes
List Prices
Production Nbrs
Tune-Up Specs
Torque Values
3-Point Specs

Tractor Games
Just For Kids
Virtual Show
Museum Guide
Memorial Page
Feedback Form

Yesterday's Tractors Facebook Page

Related Sites
Tractor Shed
Ford 8N/9N Club
Today's Tractors
Garden Tractors
Classic Trucks
Kountry Life
Stationary Engines Discussion Forum

Re: Understanding how the coil works on an onan 2 cylinder

[Show Entire Topic]  

Welcome Guest, Log in or Register
Author  [Modern View]

10-27-2011 06:57:00

Report to Moderator

It is a "waste spark" system. Both spark plugs fire at the same time... one on it's cylinder's compression stroke and the other on it's cylinder's exhaust stroke (where the spark is "wasted").

The secondary winding is NOT grounded at one end or connected to the primary (as it is in typical ignition coil).

A lead from each end of the primary winding goes to to a spark plug. One fires with a positive-going pulse and the other with a negative-going pulse.

MANY automotive engine from the 80's up use the same type of system, having half as many coils as there are cylinders.

[Log in to Reply]   [No Email]

11-11-2011 04:30:32

Report to Moderator
 Re: Understanding how the coil works on an onan 2 cylinder in reply to Bob, 10-27-2011 06:57:00  
About your comment "A lead from each end of the primary winding goes to to a spark plug"

Is that a typo? I assume you mean the plugs are hooked to each end of the secondary windings?

[Log in to Reply]  [No Email]

10-27-2011 09:55:51

Report to Moderator
 Re: Understanding how the coil works on an onan 2 cylinder in reply to Bob, 10-27-2011 06:57:00  

Thank yor for the information. A regular coil with one wire and primary wire to the points would not work, provided I understand your explanation. Another question: Removal of the flywheel:I've used two pry bars and a brass drift to strike a blow with a hammer on the crankshaft nut. What is the proper type of puller?

[Log in to Reply]  [No Email]
[Show Entire Topic]     [Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:

Fast Shipping!  Most of our stocked parts ship within 24 hours (M-Th). Expedited shipping available, just call! Most prices for parts and manuals are below our competitors. Compare our super low shipping rates! We have the parts you need to repair your tractor. We are a company you can trust and have generous return policies. Shop Online Today or call our friendly sales staff toll free (800) 853-2651. [ About Us ]

Home  |  Forums

Copyright © 1997-2018 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 Headquarters