'77 Johnson 140hp - Flywheel sticks periodically when trying to start

[texasatm2011]

Ok y'all, let me see if I can explain this so that it makes sense.

When starting my '77 Johson 140hp outboard, I typically lift the choke, turn the key, and start the motor... simple.

Sometimes the motor starts, I depress the choke lever, and the motor dies so I have to go through the process again until the motor stays running. It usually always starts on the second try.

This weekend I got to the lake and started the motor. As usual, I depressed the choke and it died so I went to start it again. This time however, the starter would not engage the flywheel. I had to turn the flywheel by hand to free it up (i actually used the emergency pull chord). Once I turned it past the sticking point, i was able to use the electric starter again. I tested it out a few more times and each time I killed the motor, I have to manually turn the flywheel past the sticking point, once I do that I can use the electric start.

This is a new starter, starter solenoid, and new battery.

Could this be carbon build-up in the pistons? Or maybe a stuck valve or piston rings?

Any help would be great!

Thanks!

- Aaron
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[gm280]

texasatm2011, I not sure what you mean by sticky area. Are you talking about the compression stroke? Or is there something else causing the flywheel to now move? If it isn't the compression causing the flywheel to not move easily, then you may have something under the flywheel dragging on it... JMHO!

 

[Bosunsmate]

no valves on 2 strokes.
grab the flywheel, try and move it, any play?

 

[texasatm2011]

I don't think anything is dragging on the underside of the flywheel but I can certainly check.

When it gets stuck there is no play at all, I have to pull pretty hard to get the flywheel to move. Once I get it un-stuck it turns like normal; that is, until the engine starts, runs for a few seconds and then dies.

 

[racerone]

Remove lower unit and test again.

 

[emdsapmgr]

From your description, sounds like the engine is binding during it's rotation. Other than normal compression, there should be no reason for any binding. You may want to pull both heads and visually inspect the pistons in the cyls. Also agree with racerone, pull the lower unit-it could be the reason for the binding.

 

[tblshur]

have u tried jumper cables straight to starter, may have power loss in solenoid or cables.good luck:joyous:

 

[Drummerhowie]

Hey there. I had the same exact problem on a 1986 Evinrude. Every once in awhile I couldn't pull start it. I pulled the flywheel and discovered that the coil in front had come loose and was moving forward into the flywheel. I JBwelded the iron core and slid it back into place, and haven't had any problems since.