JD B - No fire

Deereman1

Member
Good Day All
Im having a firing issue while restoring my 51 JD B. Its a wico Distrubutor and changed from 6 to 12 volts. I have power to the distributor however no spark in the points. I had brought the coil to an older experience mechanic to see if it working. He could not checking it properly as he had sold most of his equipment, however it does have resistance on both wires from the coil and in his opinion, he doesn;t believe there would be anything wrong with the coil. (no burn smell etc). He thought it most likely the condenser or points or both.
I bought and replaced both points and condenser. I now have spark in the points but still no spark to the plugs. I checked the plug wires and they are working good. Also have new plugs. Where should I go from here? Is there any other way of finding out if the coil is actually working before I buy one. What else should I check?
All help would be appreciated
Thanks
 
My opinion only.......Throw that wico distributor down a volcano some where and replace it with a delco dist, or a wico X magneto.
 
cost of mags were affecting the cost of the tractor so John Deere came out with that piece of sh...…….. Like the other post throw it away....
 
It might not be the best distributor, but should still work.

I have heard other people post "fire at the points", what does this mean?

Pull the coil wire out of the distributor and see if you have "fire" there, should jump a 1/4 nice blue spark.

If fire there, then none at the plugs it is a rotor issue.
 
You should not have fire at the points. This means your points
are dirty or you have a bad condenser. If you are using 12
volts. You need a resister or your points and coil won't last
long.
 
"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">I have heard other people post "fire at the points", what does this mean?[/i:654c4848f0][/b:654c4848f0]</font>"

If there is power from the coil

a270898.jpg" width="650"


and power from the primary terminal stud,

a270901.jpg" width="650"


then there is power at the distributor contact points.

a270903.jpg" width="650"


Hope this helps.
 
Last year i worked on a B for a guy that had the Wico distributor with no spark. He thought it was a mag and i had to take it apart for him to convince him it was a distributor. He wanted it left on the tractor. He did not want a Delco because he wanted it exactly the way it was when he grew up on it. I finally got spark but it was weak so in the end i got a new coil for it too. That gave it good spark but was expensive. The advance linkeage was worn out and i couldnt come up with new parts so i manufactured new linkeage. Thank god that linkeage is hidden from view because it isnt some of my best work. He ended up with quite an investment in that Wico after paying for my labor plus the new coil. So like the other guys mentioned you can put a Delco on it and have fewer and cheaper problems in the future. Dont throw the Wico away though. Someone else might need some parts from it.
 
Are you sure it is a distributor not a mag?????????? If it is a mag and you hooked battery power to it then you have let the smoke out of it big time.

If your 1000% sure it is a distributor then try these things.
With the points closed remove the ignition side wire off the coil and turn it on. Now touch that wire to the coil and then back off. When you do that you should get a spark. No spark means points are dirty/corroded. If you get a spark then get the point to a point there open and try that again. If you then have a spark then you have a short in the distributor and you need to find that short or you will not ever get spark
 
James, Mine don't look like that. I am trying to upload a pic but having problems with it. it is a 6 to 12 volt but I do have a resistor. Like I mentioned, I have replaced the condenser and points and now at least I have spark at the points but noting any further then that it seems. I have tested the plug wires and they are good.
 
Have spark at the point but not to the plugs means either you forgot to put the rotor back in or the rotor is bad or the cap is bad. As for testing the plug wires how did you do that??. You can test them to see if they read zero ohms but hard to test them to see if they leak off spark unless you want to grab them in your hand. Also you may try putting the old condenser back in now days you have a50/50 chance of having a bad condenser right out of the box. I my self have not changed a condenser in over a decade because of that
 
The new XB Wico dist. that was installed on a 12volt system came with instruction to add a second resistor. This info came with the new unit from Wico. A Delco will fail if you don't have some type of resistor. If you get a Delco BUY the coil & resistor package here on YT parts converting to 12volt system. I have used them and they work great.
 
"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">I am trying to upload a pic but having problems with it.[/i:654c4848f0][/b:654c4848f0]</font>"

This is one method/way of posting a picture in Classic View.

Scroll down to [b:654c4848f0]Advanced Posting Tools[/b:654c4848f0] area.

a224674.jpg" width="650"


Select the <font color="#6699ff">[u:654c4848f0][b:654c4848f0]Upload Photo[/b:654c4848f0][/u:654c4848f0]</font> link and the [b:654c4848f0]Photo Gallery Upload[/b:654c4848f0] dialog box appears.

a224675.jpg" width="650"


Click the Browse button, then locate and select the picture you want to post.

a224676.jpg" width="650"


Click the Open button and return to the [b:654c4848f0]Photo Gallery Upload[/b:654c4848f0] dialog box.

a224677.jpg" width="650"


Click the Upload button and a thumbnail of your photo will appear.

a224678.jpg" width="650"


Click the Continue button to complete the upload.

Click the Preview Message button and your photo will appear at the top of your message.

a189551.jpg" width="650"


Hope this helps.
 
"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">Is there any other way of finding out if the coil is actually working before I buy one.[/i:654c4848f0][/b:654c4848f0]</font>"

You might consider using a test light to determine if power is flowing through the coil.

Turn the ignition key [b:654c4848f0]ON[/b:654c4848f0].

Touch the lead wire to the coil.

If the light shines, then there is power to the coil.

Touch the lead wire from the coil.

If the light shines, then there is power from the coil.

You might also consider using a multimeter to measure the amount of current flowing/passing through the coil.

I was unable to find any specification for an Ohm range reading.

Hope this helps.
 
Ah but if things are working as they should be a test light does very little good unless the points are open. If the points are doing as they should there closed most of the time and then the coil should not have enough voltage to light the test light unless the points are bad or open.
 
"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">if things are working as they should be a test light does very little good unless the points are open.[/i:654c4848f0][/b:654c4848f0]</font>"

Revisited my reply above.

"[i:654c4848f0]You might consider using a test light to determine if power is flowing through the coil.

Turn the ignition key ON.

Touch the lead wire to the coil."

a270964.jpg" width="650"


"If the light shines, then there is power to the coil.

Touch the lead wire from the coil."

a270965.jpg" width="650"


If the light shines, then there is power from the coil.[/i:654c4848f0]"

Note that the lead wire from the coil is not connected to the distributor.

How does the coil determine if the points are open if it is not connected to the distributor?
 
This is a difficult post to make a response. Wico on these distributors used the same design if not the same housing as the impulse mags. The only problem was the weakness of the coil. I'm confident these items were left switched on and a lot of them damaged. The coil itself is under rated if not defective in design. Mags were better as they get hotter with acceleration. I don't understand why this defective part is giving so much attention. But good luck trying to get it to operate efficiently.
 
If thing are as they should be the points ground the coil and when the point open the coil makes the spark simple as that. Hooking a test light up to a correctly wired system the test light only comes on when the points are open or if the points are bad
 
James Howell, thanks for the post on uploading pictures!

As to the distributor problem, I had the same issue with a Wico distributor on my late model B last year. A lot of people gave me great advice because I was trying to keep the tractor like it was. But eventually I just swapped out the distributor for a mag and it then ran great. By going to the mag I kept closer to the appearance of the way the tractor was than if I updated to a Delco distributor. I'm sure it would have worked either way, but I had the mag on hand.
 
Uploading pictures is a common "[i:654c4848f0]how to[/i:654c4848f0]" question on the various YT forums.

Thanks for the update on your tractor.
 
Thanks for all the help here. To clarify something that someone said earlier, I did leave the key on and the distributor did get hot. It ran fine until that point. I then noticed there was no fire on the plugs. I changed the condenser and points and now at least I have spark at the points, (which I didn't have before). With spark at the points, does this actually mean my coil is good? Also is it normal for the resister to get hot? I also did what James mentioned earlier with the test light. I was getting power on the red wire from the coil but not the black, however I just read that the points have to be opened. I will try this again.

Thanks again
 
Update: Ok so I light tested the black and red wire from the coil with the points open and the ignition on and I DO have power???
 
Take a look at the [b:654c4848f0]DISTRIBUTOR (WICO) AND IGNITION LOCK[/b:654c4848f0] diagram below.

a271033.jpg" width="650"


Note the ignition switch to distributor lead (Key 47).

Take a look at the photo below of the distributor on your tractor.

a271035.jpg" width="650"


My first question is this red wire connected to the ignition switch? (Yes or No)
 
With the facts...key left on...points were closed so current load has burned out the coil....replace the coil..points..condenser and then see what you have....
 
Am I right in thinking that the top wire on the distributor goes to the left side of the tractor(flywheel side)??
 

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