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
Farmall & IHC Tractors Discussion Forum
Show Parts for Model:

Re: farmall m electric problem

[Show Entire Topic]  

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

11-06-2012 04:51:03

Report to Moderator

A cheap low quality ohm meter may not be very accurate at low ohms reading like say 1.5 to 2 ohms which a typical ballast resistor is.

If you unhook the wires to it and measure the ballast resistor resistance, Id expect maybe 1.25 to under 2 ohms, if its open (infinite resistance no continuity) its obviously baddddddddd.

With all hooked up like normal with the ignition ON if you place a DC volt meter ACROSS the ballast and if the poitns are good and closed and all is working, Id expect around a 6 volt drop.

If (all ON and working and points good and closed) you place the meter with Neg to frame case ground and the positive to the coils input (NOT to distributor) Id expect 6 volts (cuz the ballast if good and conducting current drops 12 battery volts down to 6).

If you put the meters Pos on the coils output (TO distributor) Id expect 12 volts when points open but 0 volts when closed.

SHES NEVER GONNA PRODUCE A SPARK UNTIL YOU HAVE VOLTAGE ON THE COILS INPUT (NOT to distributor) with the ignition ON and that means a good and conductive ballast resistor after the ignition and bepore and ahead of the coils input.

I suspect an open or burned circuit somewhere in the Ignition primary (switch, ballast, coil, points) GET YOUR METER OUT N GO TO WORK

Run my Troubleshooting procedure

John T

[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