Intermittent spark

[markseven 88]

Not sure but im getting frustrated trying 

To figure it out.

Cleaned points and .020 set at.

Have a good 12 volt to coil

All new wires .

New coil  .

Kohler k301  12 hp

Will not start 

Everything is basically new other 

Than the sparkplug  and sparkplug wire. 

Edited 6 hours ago by markseven
Yyy

[Achto 30,548]

1 minute ago, markseven said:

Not sure but im getting frustrated trying 

 

Intermittent spark ??? Are you losing spark at high RPMs, when it gets warm, or all the time?

 

Cutting out at high RPMs could be the condenser.

Cutting out after a short period of time could be wrong coil - "with out an internal resistor". Battery voltage builds up above 13vdc and collapses the coil.

Cutting out all the time could be dirty points or a bad plug. After you file or run sand paper through the points, you should follow up with paper or a dollar bill.

[markseven 88]

I found the problem. 

Had this bolt to tight. 

It should actually be a 

Pin and cotter key.

It was putting to much pressure on the crankshaft towards the flywheel side

And actually turning engine over hard.

Causing a voltage drop enough to 

Cause the intermittent spark.

 

[Ed Kennell 44,164]

Is this engine not equipped with an axial thrust bearing to handle the thrust from a manual PTO.    Seems the Manual would exert more thrust than tightening that bolt on the lectric PTO ?      

 

 

But, I guess we never start up with the manual PTO engaged.    Might be interesting to bypass the PTO safety switch to see if one would start with it engaged.

 

Still thinking about this.    The engaged manual PTO exerts  a true axial force at the center of the shaft which the thrust bearing can handle.

 

Tightening the bolt shown exerts a bending force on the electric PTO bearings that may be causing enough friction in the PTO to make the engine difficult to start.     

Edited 4 hours ago by Ed Kennell