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

Garden Tractors Discussion Board

Re: 1970 14 hp kohler no spark

[ Expand ] [ View Replies ] [ Add a Reply ] [ Return to Forum ]

Posted by Bob on December 03, 2013 at 09:26:48 from (

In Reply to: Re: 1970 14 hp kohler no spark posted by wayne huber on December 03, 2013 at 08:04:32:

I do NOT believe there's a way to operate the module by powering it b y battery voltage, and such an attempt will "let the smoke out", if in fact it IS still functioning.

Here's MY interpretation of how this system works, FWIW. Did you check AC voltage out of the stator with the trigger module unhooked from the stator? The way I understand this system, the stator makes AC, the trigger module rectifies it to DC, which is stored in the capacitor built into the coil.

When the tab on the flywheel passes the trigger, an SCR is "fired", which rapidly discharges the capacitor in the coil, causing current in the coil primary that is "stepped up" by the turn ratio to a high enough voltage to fire the spark plug. (A type of "CD" ignition.)

The open-circuit AC voltage out of the stator would be one thing, beyond that (whatever the correct value should be), the diode(s) in the module have to be OK to make the DC voltage, the SCR must not be shorted or leaky, and the coil and capacitor must be functioning so a DC voltage builds up between spark events so the coil is able to be fired.

So, if you are measuring DC voltage at the coil terminal and it's actually low, the fault could be in the stator, the trigger module, or the coil.

Are you aware most likely you CAN install a plunger and a set of points and a coil and convert it to Kettering ignition? (Seems to me certain blocks were not drilled for the plunger or point mounting holes. Normally, the holes are there and the plunger hole is plugged with a little "cup plug".

If you GGOGLE "Kohler 237750S" you will get info on what is involved.


Add a Reply



Optional Link URL:
Link Title:
Optional Image URL:
Optional Video Title:
Optional Video Embed:

Advanced Posting Options

Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks.

Advanced Posting Tools
  Upload Photo  Select Gallery Photo  Attach Serial # List 
Return to Post 

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