1990 15 hp Johnson won’t start, sort of sounds like it’s sucking air/leaking air

[David wright]

I’m a nurse by trade and completely self taught. My dads mechanical knowledge is pretty much 0. Most everything I do is trial and error or stuff I find on here. I’m trying to become more competent with every motor. I’m 34, so 99% of these motors are 20+ years older than me. None of my buddies know anything about these old 2 smokers. I’m stuck figuring it out for myself

Thats why these threads are here to help everyone gain experience through success and faliure,

 

[racerone]

If you put fuel directly into the sparkplug holes the motor should---BARK---If there is no response you have no spark or spark at the wrong time.

 

[David wright]

If you put fuel directly into the sparkplug holes the motor should---BARK---If there is no response you have no spark or spark at the wrong time.

Yes this means a timing issue and he has already said he has a spark this is why I said about the woodruff key, the only other think I can think of on timing is the magnets under the flywheel being worn giving an of piste spark but even then every now an then the exhaust would give out a puff

 

[jitterbug127]

If you put fuel directly into the sparkplug holes the motor should---BARK---If there is no response you have no spark or spark at the wrong time.

I’ve got Spark so it’s gotta be timing then. Great!

 

[jitterbug127]

Let me shoot a video of my spark show the flywheel. It might give some insight

 

[jitterbug127]

My spark looks more white than blue but might be the lighting…I’m not sure if they means anything to you guys or not.

 

[racerone]

Checked the flywheel key today or 2 weeks ago ?

 

[jitterbug127]

Checked the flywheel key today or 2 weeks ago ?

Today.

 

[jitterbug127]

Did this picture go through?

 

[David wright]

Checked the flywheel key today or 2 weeks ago ?

This is a good point as if the flywheel isn't seated properly after removal it can shear easily ive done it myself

 

[jitterbug127]

This is a good point as if the flywheel isn't seated properly after removal it can shear easily ive done it myself

Me too on my 6 hp

 

[David wright]

Me too on my 6 hp View attachment 388347

Haha mine was only last week

 

[David wright]

Yes all looks ok and if the magnets were in bad condition you wouldn't get a spark to both cylinders so as the post before said are you sure you seated the flywheel correctly its sited with no movement (rocking) and tightly fitted to the correct torque i believe on your engine its 40 - 45 lbs

 

[jitterbug127]

Yes all looks ok and if the magnets were in bad condition you wouldn't get a spark to both cylinders so as the post before said are you sure you seated the flywheel correctly its sited with no movement (rocking) and tightly fitted to the correct torque i believe on your engine its 40 - 45 lbs

Fly wheel is on their good. No rocking and properly seated. Torqued with my wrench

 

[David wright]

Fly wheel is on their good. No rocking and properly seated. Torqued with my wrench

Ok can you show an attempt at a start

 

[David wright]

And maybe just check the woodruff/flywheel key just one more time before you do

 

[jitterbug127]

Ok can you show an attempt at a start

Will do!

 

[David wright]

 

[David wright]

Are you sure this key isn't sheared it looks broken and sheared at the top

 

[David wright]

With the flywheel in place without the locking nut you should see the woodruff/flywheel key engadged tightly into the slot on the flywheel yours looks flat at the top and broken and protruding at the bottom of the crankshaft