(800) 853-2651
SHOP NOW

Farmall M Timing - Bosch Magneto

I

IAtractorKid

Member
Hey guys! Finally got the new head on the M and was able to run it for about a half an hour. Got it up to operating temp and then shut it down so I could retorque the head and re-adjust the valves. Anyway when I went to shut down, it was still dieseling a little which leads me to believe the timing is off. Anyway the tractor has an American Bosch Corp magneto, which I have never seen on another M and have no experience with. I tried timing per my operators manual, it says the impulse coupling should click at TDC on compression stroke of #1 cylinder if correct...I have done this a few times with IH magnetos and had no problems. But this Bosch magneto has no "click"...should it? I was just going to set it based off of the point opening but was not sure if it should spark right at TDC, before or after?

Thanks for any and all help!
 
A large number of IHC tractors that came to New Zealand in the early stages of the Second World War were fitted with American Bosch magnetos. It is also interesting that a large number of IHC tractors with IHC H4 magnetos were fitted with shields or covers over the magnetos. Maybe the H4 was not as waterproof as IHC claimed.
 

It should spark at TDC, or no more than 2* after. I hand crank my H, so I want 1* or so of safety margin.
 
If the impulse has no click, snap, that is your problem. Not familiar with Bosch Magneto but have seen a few battery ignition systems that look, from the outside to be a magneto when in fact they are not. Most people refer to battery ignition as being a distributor. That is one of my pet peaves because any four cyl magneto also has a distributor on it. Rotor, distributor cap.
 
You must log in or register to reply here.

Similar threads

R
John Deere H Timing
2
Replies
28
Views
1K
Mike(NEOhio)
M
P
Farmall H Magneto Question (American Bosch MJB4A-308)
Replies
7
Views
775
560Dennis
560Dennis
B
1927 D Ignition Timing
Replies
2
Views
277
Bikesmith
B
T
1948 John Deere magneto timing
2
Replies
35
Views
1K
rustred
rustred
A
Farmall M electrical
Replies
7
Views
439
BarnyardEngineering
BarnyardEngineering
Tractor Parts Tractor Manuals

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.

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 Headquarters
Website Accessibility Policy

Back
Top