Farmall a dies when warm no spark?

Anonymous-0 · Oct 3, 2014

Tractor when cold starts up after 30 minutes it sputters,I put a spark light tester on that you plug into the wire then it goes onto the spark plug it self. When it first starts It lights up every time it fires after awile it starts to sputter and no flash from tester. What is the problem? I check the points/gap rotor cap change wire from points to condenser.. I'm stumped h4 magneto

Jeff McBride · Oct 3, 2014

condenser

Nebraska Cowman · Oct 3, 2014

Or coil. Fails when warm.... classic symptom.

gene bender · Oct 3, 2014

probably the coil

Geo-TH,In · Oct 3, 2014

Many years ago my dad's old cub did the same thing. So I used an external coil, the points and condensor inside mag and external ballast resistor. It worked.

souNdguy · Oct 3, 2014

got a spare coil and condensor to check with.

as has peen posted. you can run them external like battery ignition, just using the points.

teddy52food · Oct 3, 2014

It was the condenser on the last H4 I worked on. It checked out ok but after putting it next to the bench light for a while , it tested weak & leaky. A new condenser and I haven't heard from him since.

Tom Fleming · Oct 4, 2014

99 times out of 100, when a mag or battery ignition starts and runs fine cold, but fails when warmed up, it is the coil. If you cleaned the points, and you know the condenser is good, you have a bad coil.

replacing a coil on an H4 is not a terribly hard job. They are a little pricey though. $50-$60 for a new one.

Farmall a dies when warm no spark?

Anonymous-0

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Jeff McBride

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Nebraska Cowman

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gene bender

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Geo-TH,In

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souNdguy

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teddy52food

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Tom Fleming

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