70HP Johnson 1979 Power Loss..

[sirius3k]

Now that i've spent many hours on the motor lower end problems.<br /><br />I find that I have a loss of power, and the idle is jerky...<br /><br />Compression check shows <br />120,122,118<br />all sparks good<br />new plugs.<br />good gas with 50-1 mix.<br /><br />Motor did sit for 3 years pistons look black.<br /><br />Used de-carb... made a differance, but not for long.<br /><br />Going to take her out in the morning and just run around the bay, and see if the power loss will clear up..<br /><br />And ideas about this please post Thank you...

 

[Joe Reeves]

Re: 70HP Johnson 1979 Power Loss..

Sirius3k.... Any engine that sits for that length of time is going to have faulty/fouled/gummed carburetors. Running the engine with carburetors in that condition will result in having the engine run lean (not a good idea). Remove, clean, and rebuilt the carburetors. If you don't have a manual, you can obtain one at the bottom of this page.