converting an old Evinrude 2HP outboard magneto from points and condenser to ignition module

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peterhull

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I recently bought a small 1981 Evinrude Outboard 2hp and decided to restore it.
I have had a bit of a job with it becuase although the cylinder and piston were free moving, some bolts were seized where dissimilar metals and been used on the alloy head. Nevertheless I am continuing the restoration, spending more than I anticpated, but I quite like the satisfaction of restoring something to a working condition.
My question is has anyone used a modern ignition module to replace the points and condenser on an older outboard . I have seen several U tube videos on this . I have bought a module only £10 intended for an Orgeon Chain saw. I think Nova maybe the original manufacturers. I would be interested in your experience if so. I have fitted mine but not finished the restoration to a working condition yet.
 
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Yes i have when i couldnt get an ignition coil. Its just a matter of getting the coil in the right place.
Personally I would put an original one back in , they are cheap and plentiful
 
Steve65 said:
Yes i have when i couldnt get an ignition coil. Its just a matter of getting the coil in the right place.
Personally I would put an original one back in , they are cheap and plentiful
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But this isn't about replacing the coil. It's about replacing the points and condenser. A coil is still needed to create the high voltage needed for the spark plug
 
peterhull said:
But this isn't about replacing the coil. It's about replacing the points and condenser. A coil is still needed to create the high voltage needed for the spark plug
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If you replace the coil for a cdi unit you throw away the condensor and points.
The complete original ignition for these are not expensive and readily available. From previous experience with these check compression...If you aint got compression dont worry about ignition. Absolute pigs to rebuild
 
Steve65 said:
If you replace the coil for a cdi unit you throw away the condensor and points.
The complete original ignition for these are not expensive and readily available. From previous experience with these check compression...If you aint got compression dont worry about ignition. Absolute pigs to rebuild
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OK Steve I didn't think a cdi unit was for this model. The BRP spares catalogue does not show one on the exploded diagram or any part number. The original was a coil plus points and condenser as far as I am aware.
who supplies a CDi unit compatible for this model, I would be interested to know
mmm I have a compression tester, so I will check it yes.
 
The CDI ignition on a Johnson (6) has a coil under the flywheel which is energised by the magnets in the rim of the flywheel. I imagine the same magnets on your points 2HP would do the job. This pick up coil both energises the capacitor and provides a point where spark is required. (timing). The coil feeds the CDI unit a sealed block mounted on the block. This unit feeds a pulse of power from the capacitor via SCR (silicon controlled rectifier) to the coil(s) which then have a high voltage wire going to the spark plug.
I presume OP wants to emulate this in a single cylinder engine. Presumably doable with components from another single cylinder engine. The critical part is the coil under the flywheel which in the 6 sits on a base which can rotate with throttle operation to give spark advance.
Perhaps this will help OP however I think he should stick with original points ignition. ol'will
 
William_H said:
The CDI ignition on a Johnson (6) has a coil under the flywheel which is energised by the magnets in the rim of the flywheel. I imagine the same magnets on your points 2HP would do the job. This pick up coil both energises the capacitor and provides a point where spark is required. (timing). The coil feeds the CDI unit a sealed block mounted on the block. This unit feeds a pulse of power from the capacitor via SCR (silicon controlled rectifier) to the coil(s) which then have a high voltage wire going to the spark plug.
I presume OP wants to emulate this in a single cylinder engine. Presumably doable with components from another single cylinder engine. The critical part is the coil under the flywheel which in the 6 sits on a base which can rotate with throttle operation to give spark advance.
Perhaps this will help OP however I think he should stick with original points ignition. ol'will
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Thanks ol'will, Interesting. I have done a little research on this and I think these tiny ignition modules contain a Hall Effect transistor and from what I can gather timing is not over critical. I think the Hall Effect transistor picks up the voltage peaks on the coil and and triggers the spark at the plug when required. Some with better knowledge of electronics may be able to confirm this or otherwise, but that is my understanding.
 
Regarding timing with the Johnson CDI no Hall effect device in the wiring diagram but it seems to decide to discharge on some repeatable point on the induced current from the pick up coil. Just not surer. A hall effect device is a transistor which conducts more or less in the presence of a magnetic field so could be used in some systems to detect passage of the magnet to fire the discharge hence spark. ol'will
 
William_H said:
Regarding timing with the Johnson CDI no Hall effect device in the wiring diagram but it seems to decide to discharge on some repeatable point on the induced current from the pick up coil. Just not surer. A hall effect device is a transistor which conducts more or less in the presence of a magnetic field so could be used in some systems to detect passage of the magnet to fire the discharge hence spark. ol'will
[/QUOTEYes Will that is my understanding re Hall Effect transistor.
I thought all cdi's had a Hall Effect transistor built into the circuit though. I would be interested to know how the CDI system works without a the HE transistor.
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I didnt fit it on an evinrude i fitted it to a 2b Yamaha.The timing needs to be correct and will be different to original.
 
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