dschild
Seaman Apprentice
- Joined
- Sep 23, 2007
- Messages
- 43
1974 70HP johnson outboard. One day at full throttle she kicked back and lost power. I pulled the throttle back, and tried again, same thing. I took it home, put the ears on and ran the motor. Saw water coming out near the bottom 3/3 cylinder. It was shooting out the right hitting one of the coils. When I revved up the motor, water shot out faster.
So took the head cover off, found blown gasket. Replaced gasket and put it all back together. Used proper torque, etc. Still had water shooting out. Thought that maybe head cover was warped. So I found an online used parts dealer recommended on here and bought a new head cover. Put it all back together (and for a guy who knows NOTHING about motors, I was pretty happy with my accomplishments at this point. I'm a computer geek) Still had water shooting out the same side. Also looked at the center spark plug 2/3 and saw that it was shiny and clean. (I did change all the plugs. Was recommended by a johnson dealer that I use gapless plugs). The 3rd plug was very dirty. I check compression, all hitting about 120 giver or take. But still 3 was very dirty and 2 was very very clean.
I took it out on the water this weekend just to see what was going on. At full throttle I only got about 7mph. Definitely not getting the power it should be. Not kicking back anymore, but not getting power. I'm guessing cylinder 3 isn't running, and is maybe because water is getting in there. Any thoughts on this? How can I stop that water leak? How do I check fire on a cylinder? Help!?! First boat, getting very discouraged (and so is my checking account).
So took the head cover off, found blown gasket. Replaced gasket and put it all back together. Used proper torque, etc. Still had water shooting out. Thought that maybe head cover was warped. So I found an online used parts dealer recommended on here and bought a new head cover. Put it all back together (and for a guy who knows NOTHING about motors, I was pretty happy with my accomplishments at this point. I'm a computer geek) Still had water shooting out the same side. Also looked at the center spark plug 2/3 and saw that it was shiny and clean. (I did change all the plugs. Was recommended by a johnson dealer that I use gapless plugs). The 3rd plug was very dirty. I check compression, all hitting about 120 giver or take. But still 3 was very dirty and 2 was very very clean.
I took it out on the water this weekend just to see what was going on. At full throttle I only got about 7mph. Definitely not getting the power it should be. Not kicking back anymore, but not getting power. I'm guessing cylinder 3 isn't running, and is maybe because water is getting in there. Any thoughts on this? How can I stop that water leak? How do I check fire on a cylinder? Help!?! First boat, getting very discouraged (and so is my checking account).