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IH CUB LoBoy Series - 154, 184, 185 Forum -- Questions and answers to all of your LoBoy related issues.

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J4 magneto problem

Sun Jul 17, 2011 5:50 pm

I have a Loboy 184. I have installed, points, condensor, rotor, winding, top cover, cap. I have constant spark out of top cover, sometimes no spark or intermittent spark out of cap. Tractor won't run. Help!

Re: J4 magneto problem

Sun Jul 17, 2011 6:31 pm

You mention new rotor (I presume new), what condition was the pinion in? If you have consistent spark from the coil, then rotor and cap are about all that's between the tower and each spark plug. What condition are wires in, and are they copper core. Mags don't like graphite wires.....

Re: J4 magneto problem

Sun Jul 17, 2011 9:07 pm

Bob:

Are you sure that you have a J-4 Magneto on that 184 Lo-Boy :?: The 184 comes equipped as a 12 volt system hence would have a distributor and coil. 184 Cub Lo-Boy Owner's Manual

Image

Image

Suggest you read the above manual and familiarize yourself with the electrical/ignition system. Then... we will be able to help.

Unless of course your Cub is not a 184 :?:

Oh, and G'day and

Image to the Farmallcub.com :big smile: Forum Family. And you have come to the right place for all things Cub related. If you click on the Site Rules, Regulations, & Important Information, it will point you to :arrow: the Welcome Wagon wherein you will find links to many useful sites and topics. One of which is the Cub Manual Server. You may also wish to check out the CubFests and Gatherings Calendar 2011 to find a gathering of fellow members where Cubs, Friends and a good time is shared by all. Enjoy!.

Re: J4 magneto problem

Mon Jul 18, 2011 6:38 pm

Rudi wrote:Bob:Thanks for replying. Yes it is a 184 LO-Boy and it does have a magneto. but thanks for trying to help


Are you sure that you have a J-4 Magneto on that 184 Lo-Boy :?: The 184 comes equipped as a 12 volt system hence would have a distributor and coil. 184 Cub Lo-Boy Owner's Manual

Image

Image

Suggest you read the above manual and familiarize yourself with the electrical/ignition system. Then... we will be able to help.

Unless of course your Cub is not a 184 :?:

Oh, and G'day and

Image to the Farmallcub.com :big smile: Forum Family. And you have come to the right place for all things Cub related. If you click on the Site Rules, Regulations, & Important Information, it will point you to :arrow: the Welcome Wagon wherein you will find links to many useful sites and topics. One of which is the Cub Manual Server. You may also wish to check out the CubFests and Gatherings Calendar 2011 to find a gathering of fellow members where Cubs, Friends and a good time is shared by all. Enjoy!.

Re: J4 magneto problem

Mon Jul 18, 2011 8:45 pm

Bob:

So I take it this 184 has been modified to 6 volt with a magneto. Well now.. that is interesting.

Spray the cap with WD-40, that might get rid of any carbon trails in the cap which might be messing with the spark. Make sure that the points are gapped correctly for a magneto - 0.013". Also make sure that there is no glazing on the points. Clean the points by pulling a piece of brown paper or even a dollar bill through the points. Then try it again. If it works problem solved, if not then I would also suspect a bad condenser, even though it was replaced, it could very well have been bad right out of the box. Try replacing it with the older condenser. I know.. off beat but it sometimes pays off. Spark plugs should be gapped at 0.023" and running Champion D-16 through D-21 (D-21's seem to be better - hotter plug) or equivalent. Make sure that you are using solid core copper spark plug wires as Rick mentioned - mags do not like composite core wires. Make sure it is timed correctly. Here is Mike's video how to on static timing a mag. Never thought it would be used for a 184 :shock: How to time a Magneto-Equipped Cub...film at 11:00

Also, did you get the timing marks aligned for the rotor?

I can't think of anything else at the moment. Try searching the archives for Magneto problems (you will probably find most of it applies to the standard FCub).

Re: J4 magneto problem

Mon Jul 18, 2011 9:36 pm

Rudi - having a mag doesn't mean it has been converted to 6 volts. Mag doesn't use the tractor electrical system This could be an older replacement engine or someone wanted a mag ignition. I suspect a worn pinion gear or the rotor was not installed with the timing marks lined up.

Re: J4 magneto problem

Mon Jul 18, 2011 9:47 pm

Duhhhh :oops: :lol: Yup certainly could be 12v. Mag is independant.. why do I keep fergettin that :big give up: Mag to me almost automatically means 6 v... not sure why aside from my two are 6v and mag equipped.. so maybe that is it. CRS and KFE .. that's me story and I will stick to that...

Re: J4 magneto problem

Tue Jul 19, 2011 4:09 pm

Bigdog wrote:Rudi - having a mag doesn't mean it has been converted to 6 volts. Mag doesn't use the tractor electrical system This could be an older replacement engine or someone wanted a mag ignition. I suspect a worn pinion gear or the rotor was not installed with the timing marks lined up.

Thank you for answering. I'm not exactly sure of the model . This is not the problem in question. The machine has a J4 magneto 6 volt system. Points, condenser, rotor, winding, topcover, wires (copper) and plugs are all new. I get constant spark out of top cover, intermittant and sometimes none at all out of wires. Pinion gear looks good. Is the line on the gear and the line on the rotor together the right alignment? Thank you for all of your help.

Re: J4 magneto problem

Tue Jul 19, 2011 4:20 pm

Bob W wrote:Pinion gear looks good. Is the line on the gear and the line on the rotor together the right alignment?
Yes....
mag rotor pinion marks.jpg

Re: J4 magneto problem

Tue Jul 19, 2011 6:06 pm

Dave:

Thanks for posting that, I was looking for it last night and couldn't for the life of me remember where it was.

Bob:

Image Any chance we can get pics of this 184?

I am getting very curious as to the history of this particular Cub. Was the original C-60 replaced or was the mag just swapped out for the distributor? If the engine was replaced, probably from an early FCub maybe? Just guessing.

However.. I would be looking at the rotor. The pic Dave posted should help. Now I am going to postulate something .. based on personal experience.... yes I am :oops: to say so, but yup done did it and it perplexed me for a long time - most of the winter because I made assumptions instead of double/triple checking my work. This might be kinda useful to double check after you have ensured that the rotor's timing marks are correct. How To Understand Firing Order. This last time I was sure that I had replaced all of my plug wires in the correct order.. but somehow I mixed up 1 and 3 .... which caused me a lot of problems. Simple boo-bbo worsened by an assumption that I should not have made.

Re: J4 magneto problem

Tue Jul 19, 2011 7:12 pm

Bob W wrote:Thank you for answering. I'm not exactly sure of the model . This is not the problem in question. The machine has a J4 magneto 6 volt system. Points, condenser, rotor, winding, topcover, wires (copper) and plugs are all new. I get constant spark out of top cover, intermittant and sometimes none at all out of wires. Pinion gear looks good. Is the line on the gear and the line on the rotor together the right alignment? Thank you for all of your help.


Rudi - from this comment I suspect we are not dealing with a 184 but rather a standard cub. Regardless - as stated, it is not the issue. If the mag is producing a decent spark the issue is delivery of the spark so I believe we are dealing with timing.
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