JD H Spark Plug Wire Question - See Pic

fpappal · Jul 20, 2018

Do I have the spark plug wire attached to the plug correctly? Does it simply snap on the end? They do not fit that tight and if I bump into the wire it often times come loose from the plug. I purchased period correct spark plug wires and I am starting to think that might not have been the best idea. What is really tricky it to get the spark plug covers on without the plug wire falling off the plug. My other tractors have the boot style where you simply push it over the end of the plug.

Thanks.

David G · Jul 20, 2018

I think you should loosen the tip on the plug, then attach electrode, then tighten tip.

Mike M · Jul 20, 2018

Tractors of that era that seemed to still have original wires left on them seemed to have the style with a "forked" end. Grabs on both sides. NAPA likely has replacement ends if you can find an older guy to look them up in the books.
On my H I tried the rubber boot type but as they stick out farther on the plug when using the plug covers I was having spark arch out to the cover. So on a model H I put the forked type on them.

James Howell · Jul 20, 2018

"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">Do I have the spark plug wire attached to the plug correctly?[/i:654c4848f0][/b:654c4848f0]</font>"

Yes.

"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">Does it simply snap on the end?[/i:654c4848f0][/b:654c4848f0]</font>"

Yes.

Agree with [b:654c4848f0]Mike M[/b:654c4848f0]'s statement that "[i:654c4848f0]Tractors of that era that seemed to still have original wires left on them seemed to have the style with a "forked" end. Grabs on both sides.[/i:654c4848f0]"

Take a look at the [b:654c4848f0]WICO MAGNETO (TYPE X)[/b:654c4848f0] diagram below.

Note the "[i:654c4848f0]forked[/i:654c4848f0]" terminals on both the right hand spark plug cable (Key 55) and the left hand spark plug cable (Key 56).

Take a look at the Wico Magneto Type X "forked" left hand spark plug cable on "Uncle Earl" our 39 Model B.

Hope this helps.

sunsettractor · Jul 22, 2018

I recently went through this, ordered a set of "original" style wires with the Rajah style ends, put them on the plugs and thought , this can't be right. It wasn't, those ends were not designed to work with the modern tips on Today's plugs I learned. See the pictures I've posted, the brass thumb nuts are available, they have a nice slot that the Rajah terminal firmly "snaps" onto to make your original style wire terminals work like they should.
I also have a box of some old stock Champion W89D plugs I use on my Styled D, and they have a tip that will work with modern style wire ends, but there is also a groove to accept the old style Rajah ends, I don't know if those tips are available, but the brass ones are.
They are available in different threads, so make sure if you order them you order the correct threads for the plugs you are using, Hope this helps....Tom

fpappal · Jul 22, 2018

Thank you, that makes a lot of sense. I never knew the name of the ends was "rajah". Now I just need to figure out what threads I have on the end of my plugs.

sunsettractor · Jul 22, 2018

Sent you an Email

JD H Spark Plug Wire Question - See Pic

fpappal

Member

David G

Well-known Member

Mike M

Well-known Member

James Howell

Well-known Member

sunsettractor

Member

fpappal

Member

sunsettractor

Member

Similar threads