Johnson AB 25 Help

[Tom]

Happy Fourth of July to you too!

OK, taking a long shot here… When you said the motor fired after adding fuel directly to the cylinders, did it just pop once? Or did it fire several times? Also, did you take the crankcase apart?

The reason I ask is this If the motor was disassembled to the point where the top half of the crankcase was removed, and the rod/piston assembly was taken out, it’s possible that the motor was assembled incorrectly. (Or you simply got it that way.) On motors with offset rods and parallel cylinders, it’s possible to assemble the motor such that spark occurs with the pistons at the bottom of the stroke instead of the top of the stroke. You can check this without taking the powerhead apart. With the rope plate removed, facing the front of the motor as if you were going to start it, rotate the flywheel until the keyway is pointing to the cylinder on your right. Then remove either spark plug and confirm that piston is at the top of its stroke. If it’s not, we can guide you through what to do next.

Tom

[stanley]

Another thing to check again at this point is spark.Even though you’ve replaced everything and set timing and points,it’s possible to have knocked something loose or out of adjustment.I’ve chased what I thought was a fuel issue only to discover that spark was insufficient.Take a moment to confirm that you have a strong blue consistsant spark that will jump at least 1/4”.

[muddog2]

When I poured gas in the cylinder it fired several times. A white puff of smoke came from muffler. I have never taken the engine apart and I don’t believe the precious owner die either. He said it ran 7 years ago. It was found at a fishing tackle call laying in the dirt partially covered. I will check to see if the pistons are at the top later today.

I checked that the spark plug wires were tight against the tabs before I put the flywheel back on. I checked the spark by placing the plugs on the cylinder and pulling the rope. Seems to have good spark. The fuel is not getting to the cylinders from the carb. Is there something I can spray into the engine intake that the carb goes over to clean it out inside? If I put my thumb over the intake on the engine and pull the rope should I feel suction?

[muddog2]

Had a few min. I took off flywheel and I turned the key to the right cylinder and took out spark plug and the piston was all the way to the top.

[The Boat House]

• This reply was modified 3 years, 2 months ago by The Boat House.

[Tom]

Remove the muffler and see if that makes any difference. The “white puff of smoke” may indicate something in there that’s not supposed to be there, and would explain why it’s not drawing fuel / air mix.

Tom

[muddog2]

Took flywheel and armature plate off, took spark plugs out, took carb off and I blew into the hole the carb go on while turning propeller. I gave it some suction also. I put it back together and checked compression again and it is at 60. I had to make a gasket for the fuel line at bowel connection. Got cork/rubber gasket material. I opened petcock valve to see if fuel line leaked. That is good now. I noticed grease leaking out of the foot so I had tilted the motor back to look at the foot and noticed gas coming out of intake tube. I shut the needle valve all the way. A few minutes later I decided to pull the rope before calling it quits for the evening and the motor ran till it ran out of gas from what went into the carb. About 8 – 10 seconds.

Putting it in the trash can tomorrow to see if it will run longer with the petcock valve open.

I am so thankful for all the help here.
Robert

[The Boat House]

• This reply was modified 4 years, 10 months ago by The Boat House.
• This reply was modified 3 years, 2 months ago by The Boat House.

[muddog2]

Got it started this morning ! It is running except now I have to clean water pump. Not working. AOMCI Facebook page.
I want to thank everyone for all the help. Never would have brought it back to life without it.
Robert

[muddog2]

Posted video on AOMCI Facebook Page,

[Author]

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