1972 evinrude 50hp 2 stroke. Crank no start.

Howdy,
As the title says.
Story:
Motor hits a wall on revs under load. Did up both carbs with new needles, floats, and gaskets. Cleaned up all jets. Carbs were actually fine after getting into them but replaced and cleaned stuff anyway.

Motor fires right up. Screams to life and happy days. Tune up on the water, making progress and then engine dies at the dock. Ended up being the neutral safety switch for the hydro electric shift was dirty (engine side). Cleaned it up, cranks over as intended. Won't start worth a darn.

Got her to come to life eventually, cleaned the sparkys up and bang she fires right up. Trying to now tune up in the driveway as she's a smidgen rough at idle and will die if I let it.

Now, she's a crank no start.

Fresh fuel, checked black and yellow kill switch wire, even sprayed a little cheater fluid to see. Holds prime, set my carb screw settings back to where they *should* be. Just a crank no start.

I have fuel, air, spark. No bang on the suck squeeze bang blow part though.

Any advice would be appreciated.

Check flywheel key.

racerone said:

Check flywheel key.

Click to expand...

Just had to Google that. I'm only moderately good with wrenches. Learn by the seat of my pants kinda fellah.

I'll give it a go. Can't be that hard right? Thanks.

Remove sparkplug for #1 Turn flywheel.----See if timing pointer is near TDC.----Slow cranking speed means that there is no spark.----So charge battery and load test the battery.----Take starter apart for inspection.

racerone said:

Remove sparkplug for #1 Turn flywheel.----See if timing pointer is near TDC.----Slow cranking speed means that there is no spark.----So charge battery and load test the battery.----Take starter apart for inspection.

Click to expand...

I just finished checking tdc and I'm good. Basically perfect. Some jackoff stole my good sockets from my van and I don't have one big enough for the fly wheel now anyway.

Battery has seen some drain over testing but I wouldn't say enough to be an issue yet. Still seeing those high cranking rpms.

I'll double check spark here, no light just eyes, and if spark is good I'll charge up the battery and take the starter gear off to clean and lube again.

racerone said:

Remove sparkplug for #1 Turn flywheel.----See if timing pointer is near TDC.----Slow cranking speed means that there is no spark.----So charge battery and load test the battery.----Take starter apart for inspection.

Click to expand...

Can now confirm, no spark cylinder 1. Good spark on #2. Swapped the two plugs to confirm and it's definitely a cylinder 1 issue.

Do you know of any other wiring to check before I get into having to source and replace an ignition coil?

Thanks.

Swap the Coils, to see if the Problem moves with the Coil
Good Spark? Can it jump a 3/8" Gap?

jimmbo said:

Swap the Coils, to see if the Problem moves with the Coil
Good Spark? Can it jump a 3/8" Gap?

Click to expand...

Swapped the cylinder 1 and 2 wires in this box here. Spark followed to cylinder 1 accordingly and cut off at cylinder 2. So ignition coil is good. Any idea what is in-between this box and ignition coil thay could be faulty?

Spark jumps plenty according to my eye, but my glasses are a little dirty lol. You can hear the spark snapping good when it jumps.

So I also swapped the 5 and 6 wires from that box to see if that would chase the spark (2 and 3 wires stayed 2 and 3). Spark stayed the same, only cylinder 2.

Does this sound like this box is this issue?

Thanks for all the help.

In preparation for needing a power pack. Could I get some advice on where is the best place to purchase and ship to Canada?

Evinrude 50272C

I currently found an after market one installed part number OEA 9375

I really appreciate any help, I've learned lots on this little journey.

Try----evinrudeparts.ca----Good people.