Briggs and Stratton 23D Plunger

Learning as we go and seeking some foresight, our B/S 23D did not have a spark. Took a look at the points, looked fairly good, cleaned them, and still no spark.

Turning the front PTO and hearing the cylinder move, the plunger does not move. Can pull the plunger out freely until it stops and turns freely.

Based on the board's experience, what is the best route from here? Is replacing the plunger a logical next step? We can not discern what type of plunger it is, a style I or II? Looks like style I. Do we break this off and remove remaining plunger and bushing with washer/threaded nuts?

Is it as likely that the plunger flat or keyway on the crankshaft is worn/damaged?

Is there something else we should look into before headed off in this direction?

Thanks in advance.

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Hi I would remove the spark plug, then hold the plunger in with your finger and turn the crank over slowly to see if you can detect any movement of the plunger, they do not move a lot, if theres no movement you'll have to check it out further, do you have the large B&S manual on the engine, the B&S Repairmans handbook covers engines from 1919-1981 CE8069 it covers that engine and many more.
If you have movement of the plunger and get the points set to about 0.020" and still no spark its probably the coil, in that case its very easy to convert to battery ignition.
GB in MN
 
There may be a lobe on the cam for opening and closing the points. I have the 23AB engine on a Toro mower. Do a search for that engine to see if there's a parts breakdown. You may need to pull the cam. Hal
PS: Magnets get weak from age, you can check them for magnetism using a flat blade screwdriver.
 
Not familiar with 23D engine but have several 300000
series engines that look much the same. There is no
lobe on cam but a short flat that the plunger drops
into to close the points and then opens them almost
immediately. They will be held open for most of the
cam rotation. Plunger travel is less than .020.
 
You can ditch the points and go with a Mega Fire or Nova 2 ignition module. Can easily be put under the points cover for a stock look. Cost under $15 shipped from several vendors on eBay.
AaronSEIA
 
I would use the Mega Fire as Aaron suggested.
Jack's Small engines has them for $21.00. Hal
1-877-737-2787
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[i:340254cae1]@ Bob[/i:340254cae1],

We have be turning the front PTO, can hear the valves open/close, sounds/feels like the cylinder going thru it's cycle.

We are not sure of the way we should be checking the cam shaft?

We are considering the Mega Fire option as well.

Thanks.
 
"We are not sure of the way we should be checking the cam shaft?"

jack6 explained that very well in his post, there is a depressed area in the cam that the plunger drops into for a portion of the cycle, then, at the end of that area on the cam, the plunger is forced outward, and pops the points open at the instant spark is needed.
 

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