6 Hp evinrude power loss

[katofishingguy]

I have a Evinrude 6Hp fisherman model early 70's that has been acting up and the last time out it got worse. When I start out it starts on the first pull and will run ok at full throttle for a little then i begin to loose power as if it is running on one cylinder. This last time out it ran poorly from the start and I had to call it a night right away. Any ideas in what could be causing this? Dirty carb fouled plug bad gasket not sure where to start any help would be appreciated.

[fish2live]

i am no mechanic but, sounds like it could be the coil

[fish2live]

i am no mechanic but, sounds like it could be the coil. usually when a coil goes it runs fine till it heats up then it quits working.

[Surface Tension]

Will it do this every time, run good when cold then act up?

Next time it acts up check for spark with new plugs.

[VMS]

What I would consider doing is start with new plugs...clean and fresh. Then, take the motor out and run it a while. If it does not act up, you probably have found your issue and are done with it. But...if it does act up, pull the plugs once the engine has cooled a little. If one of them is wet and/or full of carbon and the other is not, you have a spark issue...which, as mentioned would most likely be a coil. Start by switching the two coils and repeat the process. If the other plug fouls up then, you found your problem.

Not sure if the plug wire is directly connected to the coil on that model, but if it is not, it might be just needing new plug wires. Over time wires get brittle and cannot transfer electrons as well. If you can pull the plug wires off both ends (coil and plug itself) switch those out first before swapping coils around. It may be just the wires are bad too...

If the plugs are both dry and have good, consistent, bright spark, then chances are it is a fuel issue.

If so, I would check your fuel filter screen(inside the fuel pump housing)...it might be clogged just a bit, casuing a loss of fuel flow at high throttle. At slow speeds, it may have enough to get fuel through but that is it.

Also you might have gunk in your fuel lines, which as it tries to run through your carb, clogs the jets a little. If you have not done so already, I would, as a preventive measure at a minimum, change out the fuel lines within the motor itself. The older lines do not seem to handle the newer fuels and thus break down and start to break off into the gas stream...clogging jets, floats, etc.

Sounds like a nice little project, but not too tough to deal with. Worst case would be a carb rebuild, but a rebuild on a motor of that size is pretty minimal in time and effort.

Good luck and let us know what you find.

Steve

[Surface Tension]

VMS, thanks for the post.

katofishingguy, in the past I've gone into great detail what the problems could be but found that giving the first logical step in trouble shooting the problem works for me now, although I may be quite sure what the final diagnosis will be, I want to take it one step at a time. So its not that I'm holding back, I just don't want to jump to any conclusions that might lead to unneeded repairs. Its also so much easier when your eyes and ears can see and hear the problem.

[katofishingguy]

Thanks for all your responses I knew I colud get some help here FM has a great bunch of people here. I have had this problem since I bought it this spring. I did change the spark plugs once and although it did seem to do better the problem did persist and it does seem to do that when it warms up or is in operation for awhile. The hoses all seem soft and in good condition as do the plug wires they seem to be newer I also thought of the screen filter and checked it seemed to be clean of dirt and debris. I will try all the easy and obvious first like plugs fuel lines etc but the coil is something I didnt think about I'm no mechanic but I'm not afraid to work on things I feel I am capable of.I'll let everyone know what I turn up. Thanks