coil ohm specs

Jan1985

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I have a B&S 125cc engine model 08P50247F1 I am getting no spark, can anyone give me the ohm values I should expect when testing primary and secondary side of coil? Or can someone tell me where I can find these specs?
 

Luffydog

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Don't know the specs but the cable on the handle you have to hold not be pulling the coil shut down far enough off the kill switch. Allowing a no spark issue.
 

cpurvis

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Don't know the specs but the cable on the handle you have to hold not be pulling the coil shut down far enough off the kill switch. Allowing a no spark issue.

I have had that happen. It was on a Craftsman mower with Briggs engine. The way that thing works is somewhat counter intuitive since it is the cable housing, not the cable itself, that moves the switch.

Coils are an inductive component and are usually rated in units called Henrys, not ohms. https://en.wikipedia.org/wiki/Henry_(unit) The average person has no way of measuring Henrys.

I'm guessing here, but checking the coil windings for continuity is probably good enough.

Hopefully somebody with better electrical knowledge will weigh in.
 

Rivets

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Today’s coils don’t have ohms specs, because inductive pickups have replaced the points and condenser. Your best test to see if the coil is good is to disconnect the kill wire and see if your have spark. If no spark, replace the coil. If you have spark, you need to find where the kill wire is shorting to ground.
 

cpurvis

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I'm guessing here, but checking the coil windings for continuity is probably good enough.

Correcting myself, a continuity test is probably worthless because if the coil wire is shorted to ground in the middle, a continuity test can't detect this.
 

Luffydog

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That's why I wanted you to check the cable first to make sure it was working before taking cover off and unplugging the kill wire and checking for spark. Because if cables not working right won't fire. What I was getting at before taking it apart.
 

cpurvis

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That's why I wanted you to check the cable first to make sure it was working before taking cover off and unplugging the kill wire and checking for spark. Because if cables not working right won't fire. What I was getting at before taking it apart.

Agreed. That should be the very first thing to check. It's a common problem and an easy fix.
 

Rivets

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I have never seen that Briggs engine with an external throttle control. It is most commonly used on the $1.98 BB mowers.
 

cpurvis

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I have never seen that Briggs engine with an external throttle control. It is most commonly used on the $1.98 BB mowers.

The cable is on the dead-man lever, or whatever it's called.
 

Rivets

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The cable you are talking about is the blade brake cable. If the OP can pull the engine over, the cable is doing its job.on most engine the kill wire is attached to the brake mechanism.
 
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