I have fixed/tested many things on this 1982 Johnson 50 HP outboard that I purchased in July 2017. New coils, powerpack (the old one was okay), rebuilt fuel pump, new plugs. Compression is good, 140 psi each cylinder.
It would not idle so I rebuilt the carburetors and it idles smoothly now. However, last fall it stopped running at full throttle, it would cut out after 10-20 seconds. This spring I squeezed the fuel bulb while at full throttle and that solved the problem. It seems like I have a fuel delivery issue.
Today, I put a fuel gauge on the output to the fuel pump with a tee-fitting while running the engine on the hose. The fuel pump output was only about 1.5 to 2 psi at a slow or fast idle. I read somewhere it was supposed to be 5 to 7 psi.
Should I purchase a new fuel pump? They are about $20 on eBay. Could it be something else? If I squeeze the primer bulb the pressure jumps up to 5 - 9 psi--then i stop squeezing. No leaks anywhere. I loosed the fuel tank cap to ensure no vacuum.
Could the pressure pulse be an issue? Anything I have overlooked? Is there a good fuel pump brand (other than OEM, as they are pretty pricey)?
Thanks for the help.
Dave.
It would not idle so I rebuilt the carburetors and it idles smoothly now. However, last fall it stopped running at full throttle, it would cut out after 10-20 seconds. This spring I squeezed the fuel bulb while at full throttle and that solved the problem. It seems like I have a fuel delivery issue.
Today, I put a fuel gauge on the output to the fuel pump with a tee-fitting while running the engine on the hose. The fuel pump output was only about 1.5 to 2 psi at a slow or fast idle. I read somewhere it was supposed to be 5 to 7 psi.
Should I purchase a new fuel pump? They are about $20 on eBay. Could it be something else? If I squeeze the primer bulb the pressure jumps up to 5 - 9 psi--then i stop squeezing. No leaks anywhere. I loosed the fuel tank cap to ensure no vacuum.
Could the pressure pulse be an issue? Anything I have overlooked? Is there a good fuel pump brand (other than OEM, as they are pretty pricey)?
Thanks for the help.
Dave.