1968 9.5hp Evinrude/Runs Very Slow?

[mrm1980]

I test drove my motor today on my 14ft Aluminum Semi-V hull. Well motor idled and ran great in a barrel at home, so i figured it was ready the for the real thing. It barely pushed the boat at all, I think my 50lb trust trolling motor pushed it just a fast or maybe faster. All i have done to it is changed the spark plugs. I know i need to clean the carb. What are the other causes of this?? And what else could i do to pin point the problem??......Thanks

 

[F_R]

Re: 1968 9.5hp Evinrude/Runs Very Slow?

In all probablility it is running on one cylinder. Remove and ground one spark plut wire and see how it runs. Then repeat with the other wire. The one that makes no difference when grounded is the one that is not doing it's job but just going along for the ride.
Next job is to figure out why that one isn't firing.

It isn't the carburetor.

Does it run better with the hood off (on the boat)??

 

[mrm1980]

Re: 1968 9.5hp Evinrude/Runs Very Slow?

I never took the hood off while it was on the boat, so I'm not sure. It did seem to run and idle better out of the water (i ran it for sec. to get fuel out). While it was in the water it never reved up it seemed to run at a low RPM even tho i had the throttle wide open. But when in neutral it would run at a high RPM if the throttle was open. If it is running on one cylinder what causes that?? And what are the things i should check to see why??....Thanks

 

[samo_ott]

Re: 1968 9.5hp Evinrude/Runs Very Slow?

sounds like 1 cylinder. usually a bad coil. could be wiring, points, anything in the ignition system but start with the coils.

 

[mrm1980]

Re: 1968 9.5hp Evinrude/Runs Very Slow?

Thanks, i'll check it out in the morning.

 

[mrm1980]

Re: 1968 9.5hp Evinrude/Runs Very Slow?

Ok I did the spark plug wire test and it is running on one cylinder, the bottom one is not getting any fire to it at all.


Dose the fact that it is ruuning on one cylinder effect the overall integrity of the motor? Once i get fire to that cylinder it will still be a good running motor right?....pending no other problems.