won't run wide open, HELP!!!!!

[jrs]

I have a 1985 20 hp Johnson outboard, it runs perfect up to 3/4 throttle but when you turn it wide open it will run about 100 to 150 yards and it acts like it runs out of gas. You can pump the primer bulb and it will run then, I have replaced the fuel pump,replaced fuel lines,cleaned&rebuilt carb,checked timing(base and pick up),<br /> SOMEONE PLEASE HELP I'M LOST!!!!!!<br /> Detonator

 

[12Footer]

Re: won't run wide open, HELP!!!!!

Greetings, Detonator.<br />You have narrowed it down greatly. We know for certain,for instance, that it is fuel starvation, because you can pump fuel to the carb manually, and it runs good. The fuel pump is not working, the vent is plugged (remove or loosen gas cap to test this), or the pickup inside the fuel tank is clogged. There is a screen on this pickup,and they plug up over nothing. Clean the tanks you are using completely.Then,remove the gauge/inlet piece off the top of the tank.The pickup is attached to this.<br />You may also have an air leak in the line somewhere, but if the line and primer bulb are new, not the most likely cause.

 

[12Footer]

Re: won't run wide open, HELP!!!!!

I forgot something important. As a MOF, it desreves it's own reply post.<br />Check the compression. Your engine uses engine compression to operate the fuel pump, and to draw fule into the cylinders on the backstroke. So, low compression = low fuel delivery.

 

[JB]

Re: won't run wide open, HELP!!!!!

Howdy, Detonator. Welcome to the board. Couple of items that wont help with this problem but might help in the future.<br /><br />1. It is not necessary to YELL AT US!!! We can all read, and read properly punctuated text much more easily than all caps.<br /><br />2. If you post a question, we can figure out that you want some help. We also know that it is not a matter of life and death, and even if it was we couldn't help any more or any faster because you SCREAM PLEASE HELP ME!!!!<br /><br />You did the right thing in describing what is wrong in your question. That will get you all of the attention that is available and as quickly as it is available.<br /><br />Good luck, the above advice from 12Footer should get you back in operation.<br /><br />Red sky at night. . .<br />JB

 

[jrs]

Re: won't run wide open, HELP!!!!!

Thanks 12 footer for the info, I have checked the pick-up tube for blockage,but its wide open. I have thought about compression but I have not checked it. What is the psi it is supposed to have? I have been working on this thing for almost a year now, it sure has me baffled, again thanks for all the help. Detonator

 

[russthemuss]

Re: won't run wide open, HELP!!!!!

I had the same thing happen to my evinrude 35 last week.After checking it all out and thinking the worst believe it or not it was a spark plug breaking down .Sure felt like a fuel problem to me.Reved right out in neutral but felt like starving at 3/4<br />worth a try if you havn't already<br />ps replace them dont clean em

 

[alcan]

Re: won't run wide open, HELP!!!!!

Hello detonator<br /> In the past I have had some problems with sucking air in the manual primer pump. Be sure you push it all the way in after priming. Also had to replace some o-rings on the shaft. Is your motor manual or remote?

 

[jrs]

Re: won't run wide open, HELP!!!!!

hey thanks russthemuss somebody told me it could be spark plug, i'm gonna try it, i've tried everything else,I think. thanks again

 

[jrs]

Re: won't run wide open, HELP!!!!!

alcan, my motor is manual, the primer pump did leak by at one time about a year ago, i then bought a brand new one, and it has been working fine since, i know that does not mean a thing, i will check it. thanks alcan for the advise.