(800) 853-2651
SHOP NOW

Case electrical system

A

Anonymous-0

Well-known Member
I have a case 770 that has had the points replaced with an electrical ignition. The tractor is running poorly and I took the coil off to inspect it and noticed when the tractor is running with the coil detached from its bracket there is an eletrical arc from the body of the coil to the body of the tractor. I assume this is not good and would like help understanding what causes it and what I should do to fix it. The second question I have is, how can I verify that the resistor, coil, and electrical ignition are compatibal with each other?
 
(quoted from post at 14:31:50 08/28/11) I have a case 770 that has had the points replaced with an electrical ignition. The tractor is running poorly and I took the coil off to inspect it and noticed when the tractor is running with the coil detached from its bracket there is an eletrical arc from the body of the coil to the body of the tractor. I assume this is not good and would like help understanding what causes it and what I should do to fix it. The second question I have is, how can I verify that the resistor, coil, and electrical ignition are compatibal with each other?
Click to expand...

The coil should not be passing electricty through the body of the coil. The Arc you describe is because your coil is bad and passing the voltage that should be going to you distributer cap and on to the plugs is shorting somewhere (often a defictive boot on the big wire or dirt and or fluid on the top of the coil). If you have an external resistor then you need a non resistor coil. If you have no resistor then you need a coil that has an internal or built in resistor. The coil grounds through the the small wire that goes to the points or IE in the distributer.

http://auto.howstuffworks.com/ignition-system3.htm

Rick
 
Then explain why the one on my Cub cadet 782 has a plastic housing ? I always have tried a coil without completely mounting it.

Either worked or didn't throwed the ones away that didn't
 
(quoted from post at 16:21:28 08/28/11) Read his post. He has the coil hanging loose & the spark is jumping to ground to complete the circuit. Normal.
Click to expand...

I did read his post and while working as a mechanic when confronted with a coil would always hook the new coil up without installing to be sure it was good before mounting. Some coils do have a body ground to suppress raido noise but nothing that passes electricty should be in contact to the body of the coil. Electricty goes through the coil to a switched ground called points or the trigger on IE. Now if the enternal coils were gounding to the body the tractor wouldn't even start because the coils would be shorted out all the time. Now a bad coild on the 2nd winding could jump enough to casue the sparking and not allowing the full discharge to go to the plugs....hence the rough running. Look at a front mount distributer on a Ford N series tractor. The body of the coil is plastic. One wire in that supplies power to the coil, one contact that goes to the points and one to the cap. No ground except the one to the points. points closed completing the circut builds power and when they open the coil discharges that power to the plugs. I may not have explained it well but thats how they work.

Rick
Rick
 
NO! NOT normal.

The coil is an autotransformer with 3 terminals, and NO internal connection between the "guts" and the case should exist!



<img src = "http://www.instructables.com/files/deriv/FC6/CXUK/F6B7Q84T/FC6CXUKF6B7Q84T.MEDIUM.jpg">
CORRECT coil schematic

<img src = "http://i54.tinypic.com/30kukpt.jpg">
Coil schematic drawn by an IDIOT/does NOT exist on an old Case tractor
 
You must log in or register to reply here.

Similar threads

B
Farmall 656 Gas no spark, has power to coil
Replies
7
Views
424
wore out
wore out
C
12 volt conversion question
Replies
13
Views
625
used red MN
U
N
1939 Case RC magneto
Replies
5
Views
255
J Hamilton
J Hamilton
R
Electrical issues
Replies
16
Views
770
Jim L WA
J
T
12 volt conversion
Replies
19
Views
603
JMOR
J
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