Older Evinrude issue

I have a older 115 Evinrude carb'd engine that looses power when you give it full throttle.
It seems to idle Ok, but when you power it on, it falls on its face.
It sometimes tries to take off but then poops out.
I have drained the fuel and replaced a power pack.
wtf. I'm at wits end.

Can a coil cause this or ya think its carb issues.

Thanks for any help.

FI

Sounds like a carb overhaul is needed

Compression check ?

Sounds like its fuel related to me. Maybe starving for fuel. Check carbs,and gas lines,and primer bulb.

With the cowling off move the control to full throttle while watching the timing advance. I have seen the timer base sticking and not letting the advance work. If motor is lean you should be able to push the choke while throttling up and help it. Most likely stick is right. You can pull the plugs that cover the high speed jets and clean and flush them sometimes. Look here: http://www.boats.net/parts/search/BRP/EVINRUDE/1980/E115TXCSA/CARBURETOR/parts.html

Gary got ya pretty well covered other simple tests to run-

Compression test is always a good idea no use chasing ghosts if your problem is internal


It very well could be a coil dropping out leaving you with three cylinders too. Simple spark tester from autozone should show that, make sure it will jump a 1/2 to 7/16 gap in the tester. You'd be surprised how well some of these old engines will idle on three cylinders I had a coil go bad and it just ran at slightly lower rpm at idle, would still go on plane but then start stumbling.

Squeeze the primer bulb if it doesn't get rock hard somethings leaking somewhere

Pull the cover off the carbs and squeeze the primer bulb if any fuel starts seeping or dripping that carb needs attention.

Try to run whatever tests you can without the engine running first because if it is a lean issue that's a quick death for a power head. That being said having someone squeeze the primer bulb while you run will bypass the fuel pump and pretty much tell you if it's fuel delivery.

On older engines you could be experiencing fuel line internal breakdown. That is where the interior of the fuel line is collapsing. Orrrr! You have a hardened diaphragm in the fuel pump. Both sympthoms are a result of ethonal fuel........

Timing, carbs, or compression. I have had the same problem for all the on a 94 120 Evinrude. Just pray its not compression problems.

My old Johnson acted just like that last time on the water,and turned out to be the fuel filter restricted with trash...Hope yours is that easy!

has the fuel pump been rebuilt? if not it is probably time, screen cleaning too.

If compression is down on a cylinder it could be a stuck rings,you can remove the head and inspect for damage,if you see none ,replace the head and then remove the plug ,put it on earmuffs ,pump a lot of 2 stroke oil in the cylinder and let it sit for a while then right before you start put a little more oil in it,'leave the spark plug out and run the motor at a fast idle for a few minutes,then check compression ,if it comes up some ,repeat the process again,

When trying to give it power under a load, not on muffs, have you tried to choke it when it tries to die. If it picks up speed after choking it is a fuel issue somewhere.

Take it to a good mechanic ,speculating can cost you a lot in the end ,if its carbs and its running lean ,even a short distance can burn a hole in a piston and then the real fun begins.