67 5hp evinrude fuel truoble?

[mlryan]

Having fuel problems? Replaced all of the fuel lines and gas line to tank including the bulb. I have to put the throttle in to the WO position to get the motor to start. I put the throttle in the WO position and in one pull of the string it starts right up and revs high. I adjust the throttle to idle and the motor stays at idle for one or two seconds and then slowly dies. When i start the engine at WO throttle and hold the engine at WO throttle it starts revs really high and then slowy looses power until the motor dies. Just rebuilt the entire cooling system and lower unit with all new seals gaskets springs impeller and housing, the whole 9 yards. I do not know if there is a thermostat on this engine. I do not know what is causing the motor to die out. It does not look like its leaking fuel anywhere. I do not know where to go from here to fix the problem. I have the seloc manuel for the motor and it does not mention this problem or how to remedy it. PLease help i've been woking on this damn thing for the entire summer and havent got it running smoothly. Its has new points, coils, and what looks like a rebuilt carb

 

[Joe Reeves]

Re: 67 5hp evinrude fuel truoble?

Try pumping the fuel primer bulb, acting as a manual fuel pump. If that cures the problem, I'd suspect a failing fuel pump or a air/fuel leak somewhere between the pump and the fuel supply.<br /><br />Remove, dismantle, clean, and rebuild the carburetor if for no other reason to know that it is not faulty.<br /><br />Note that those extremely high revs will result in having that engine throw a connecting rod through the block.<br /><br />Adjust the carb as follows:<br /><br />(Carburetor Adjustment - Single S/S Adjustable Needle Valve)<br />(J. Reeves)<br /><br />Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.<br /> <br />Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.<br /> <br />Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting. <br /> <br />Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.<br /><br />When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

 

[mlryan]

Re: 67 5hp evinrude fuel truoble?

I tried pumping the primer bulb when the engine starts to die and it didnt pick up speed at all. Just put in a new fule pump diaphramand replaced all hoses on the entire motor frm tank to exhaust and used hose clamps to make sure there was a good connection. any suggestions?<br /><br />As soon as i get it to stay running i will adjust as you said joe.

 

[mlryan]

Re: 67 5hp evinrude fuel truoble?

another thing i neglected to mention is whhen i start it in WOT in full choke it starts. When i try to take off the choke it winds really high then dies down really fast. Dont know if that will help