!939 B magnetto

greenguy1934

New User
I have a 1939 Styled JD B it was origaly my grandfathers but he saddly pased 4 years ago. I took the task of restoring his tractors the B had leaks but they have been fixed. I rebuilt the carborator and repaced the plugs. Tryed to pull it to start it it ran for 30 seconds and died. The oil is new so is the gassoleen and the plugs so i think it could be the magnetto but it is properly timed any tips they would be glady apressated
 
If you have a hot blue spark, it is not the mag. Check for a good gas flow to the carb, (open drain on carb bowl and turn gas on) make sure it is constant. Also check for restricted air flow to carb. (mud dauber nests in air stack etc.) If all is OK on fuel and air flow, check your tappets. If a little tight, they swell with heat, and may not be closing fully. Hope this helps you.
 
Take the flywheel side plug out and ground it against the frame or something. Roll the flywheel past L H Impulse and you should have a good blue spark. To check the other one, simply reverse the wires on the mag and roll it so that the impulse trips for that side. Make sure you switch the wires back.

It's also possible that you have the idle screw set too rich which can have the effect of not opening the choke after it is running. Or even did you open the choke?
 
"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]it ran for 30 seconds and died.[/i:654c4848f0][/b:654c4848f0]</font>"

Take a look at the diagram below.

a239491.jpg" width="650"




Note the fuel control rod (Key 22) and the shut-off valve (Key 39).

Check to make sure that the shut-off valve is open.

Take a look at the photos below of "Uncle Earl" our 39B.

a239492.jpg" width="650"




Check to make sure that the fuel control rod is turned to the [b:654c4848f0]F[/b:654c4848f0] (fuel) position.

a239493.jpg" width="650"


Follow the suggestions of [b:654c4848f0]Old Popper[/b:654c4848f0] after the fuel is turned on in both locations.

"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]i think it could be the magnetto but it is properly timed[/i:654c4848f0][/b:654c4848f0]</font>"

Take a look at the diagram below.

a239496.jpg" width="650"


Note the condenser (Key 44).

You might consider checking/replacing the condenser.

Hope this helps.
 
(quoted from post at 09:12:25 01/05/17) Thank you all so much the tractor has ran for the first time in seven years if you would like to see i will send a link
Untitled URL Link
Glad you got it going. What did you find wrong? I have one I'm having a spark problem.
 

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