6 hp johnson won't start

frizzell

Cadet
Joined
Feb 27, 2002
Messages
9
I have an early 70's 6 hp Johnson that won't start. I replaced the gaskets, plug wires, plugs, <br />condensors, and rebuilt the carb. I get good spark on both plugs and fuel to the carb, but no <br />fuel gets to the combustion chamber. The compression is 40 psi on both cylinders. When I squirted<br />30 weight oil into the spark plug hole the compression jumped to 60 psi. Could I have set the <br />point gap wrong? Is the compression too low? Should I replace the rings? I cleaned the leaf valves<br />and they look ok but possibly they need replacing. Any ideas?
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: 6 hp johnson won't start

Hi Frizzell.<br /><br />This post looks awfully familiar, have you posted this question before?<br /><br />As I said to a similar post, your rings are probably nearly worn out and your cylinders may be scored as well.<br /><br />Nevertheless, if you have spark and the carb is getting fuel and it is clean it should start with correct starting procedure. Try spraying a bit of fuel mix in the carb before you try to start it.<br /><br />The only other possible I see is a broken flywheel key, throwing the timing off too far.<br /><br />Points should be set at .020, plugs to .030.<br /><br />Let us know what you find. :)
 

frizzell

Cadet
Joined
Feb 27, 2002
Messages
9
Re: 6 hp johnson won't start

Thanks. I gave it a try and the motor eventually started, after I almost pulled my arm out of joint and got a blister on my finger! Thanks for the tip, I really worked hard to fix the motor and then when it wouldn't start I was heartbroken.
 
Top