Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo Auction Link (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Farmall & IHC Tractors Discussion Forum
:

No spark at plugs

Welcome Guest, Log in or Register
Author 
ffolkes

08-23-2004 21:54:38




Report to Moderator

Hello-

I've gotten to the point in my B restoration where I'd like to make sure the engine is working. When I started this project, it ran fine.

I get a nice, big spark off the magneto, but after that it never makes it to the plugs. I verified all the wires are good, the distributor cap is good, the rotor is good, so what's wrong?

It may help to know that both the governor gear and the magneto were taken off. I know the governor gear had a punch mark to time it with the other gear…does the magneto need to be timed with the governor gear?

Something else that I wonder…on the side of the magneto is an insulated terminal which gets grounded to stop the tractor. According to my ohm meter, there’s a short between that and chassis ground. Is this normal when everything is standing still?

Thanks for any ideas.

ffolkes

[Log in to Reply]   [No Email]
Gene

08-24-2004 06:12:10




Report to Moderator
 Re: No spark at plugs in reply to ffolkes, 08-23-2004 21:54:38  
Insulated terminal. I'm not sure how your are taking the ohm meter reading. If one probe is on the terminal and the other on a ground you will get a reading. That's normal. If you are getting spark then the terminal is not shorted to ground.



[Log in to Reply]  [No Email]
magman

08-24-2004 05:08:54




Report to Moderator
 Re: No spark at plugs in reply to ffolkes, 08-23-2004 21:54:38  
I dont know exactly what you mean by a short.But Yes the mag needs to be timed to top dead center #1 firing on #1 In cap. If you take your coil wire and hold it next to the screw on the side coming from the coil cover and turn it over you should have spark if you do and it does not go any further when you put the coil cover in the cap its the cap rotor or wires, and or timing but you will still have spark if the timing is off. If you think theres a short unhook that wire to the side it just grounds to shut off the spark you dont need it to start but you will have to shut it down by some other means or ground the screw to the frame with a wire or screwdriver. Try all this and let me know. JON

[Log in to Reply]  [No Email]
ffolkes

08-24-2004 10:53:23




Report to Moderator
 Re: No spark at plugs in reply to magman, 08-24-2004 05:08:54  
Well, what I meant was there is continuity between that terminal and ground when the engine is standing still. When I crank it I get a spark, and when I specifically ground out the terminal with a jumper wire, I don't get a spark anymore. Exactly how it’s supposed to work.

In other words, the magneto part is working normally. Disregard that portion of my post from last night.

My problem is with the distributor (or so I think). There's continuity between the wire that goes to the magneto and the inside of the center post. But for some reason, the spark never makes it to the other posts. I even tried another rotor.

I just don't understand why I get a good spark off the magneto, but it won't go up the post, through the wire, and to the plug. I tried different wires, and still no change.

I don't see how this could be related to timing, since the distributor cap is keyed, the rotor is keyed, and the magneto is keyed. The magneto/distributor was never taken apart by me or altered in any way.

Thanks for any help.

ffolkes

[Log in to Reply]  [No Email]
ffolkes

08-24-2004 09:36:29




Report to Moderator
 Re: No spark at plugs in reply to magman, 08-24-2004 05:08:54  
I followed the manual's instructions for timing, but I don't understand the point.

The governor gear is linked to a specific point on the other gear, so therefore so are the magneto "lugs". The lugs interlock with the magneto shaft which goes through the magneto and ends with a keyed shaft for the rotor...what is there to "time" if everything is gear driven, and keyed?

Thanks.

ffolkes



[Log in to Reply]  [No Email]
MagMan

08-24-2004 13:30:17




Report to Moderator
 Re: No spark at plugs in reply to ffolkes, 08-24-2004 09:36:29  
Yo you need to slow down. If you have spark at the coil wire coming from the coil cap Quit testing stough. It sounds like a bad rotor or cap does the rotor gear turn. Thats the post that the rotor slides over? If yes does the rotor lock in to it? If yes is the little black grey thing I cant think for the life of me what its called but its in the center of the cap on the inside and is spring loaded It supposed to touch the rotor when you put the cap on Is that still there? other wise it has to work. You dont have a distributor rotor on your mag do you?they are alot smaller. Try these things and get back to me if it does not work give me your # and I will call you. JON

[Log in to Reply]  [No Email]
ffolkes

08-24-2004 16:40:05




Report to Moderator
 Re: No spark at plugs in reply to MagMan, 08-24-2004 13:30:17  
The distributor is on the magneto. If I take the magneto off, and hold the rotor while moving the magneto "lug" interlock, there's no play. This suggests to me that the magneto/distributor itself is working properly.

On the inside of the center post is what looks to be a little piece of spring loaded carbon.

I replaced the rotor, and that made no difference.

What could happen to the cap to make it fail so suddenly?

This is what I've done:

1. Tractor ran fine.
2. Removed magneto to clean the outside of it.
3. Primed/painted the whole thing.
4. Realized the distributor cap should have been left black, so I removed all the paint from the cap.

In that line of events, how could the cap suddenly fail? :/

Thanks for any insights you may provide.

ffolkes

[Log in to Reply]  [No Email]
MagMan

08-24-2004 17:05:03




Report to Moderator
 Re: No spark at plugs in reply to ffolkes, 08-24-2004 16:40:05  
The only thing I can think of is maybe the spark is jumping aroun inside the cap and not where it belongs.Is the carbon touching the rotor when you put the cap on you can dab a little grease on it ti see when you open it up you will see where it hit. Or When I was a kid we used to take a lead pencil and draw inside somebodys distributor cap and the spark would jump all around and would not start or run corectly becuase of the tracts. Do you think something like that may have happened ? Not thaT SOMBODY SABOTOGED IT BUT ONE OF THE PAINTS OR SOLVENTS YOU USED MAY HAVE DONE IT. dO YOU HAVE A EXTRA CAP TO TRY? Sorry I hit the caps by mistake. Let me know. JON

[Log in to Reply]  [No Email]
Bill in Orono,MN

08-24-2004 17:59:41




Report to Moderator
 Re: No spark at plugs in reply to MagMan, 08-24-2004 17:05:03  
Have you any spark at the dist. cap??

Your plugs are new yes?? If not they need to be. I had a similar problem, my 6 month old plugs seemed to be the problem.



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

Hop to:


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. [ About Us ]

Home  |  Forums


Copyright © 1997-2023 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