Weak Spark=No Power?

[mstritt]

After posting and receiving good advice I have another question. I have a 1983 70HP Johnson and was wondering if a weak spark would keep the engine from developing full RPM under load. I have done just about everyting else I can think of-rebuilt carbs(rechecked again), new fuel lines, new fuel pump, good compression. The engine rev's up fine with the warmup lever just doesn't when you are trying to go somewhere. Thanks in advance for any responses.<br />Martin<br /><br />Didn't know anything about outboard motors but I'm learning now!!

 

[fireman 757]

Re: Weak Spark=No Power?

sounds like a weak coil/powerpack. Can you get someone to pull the spark plug wires one at a time while you are under a load (totally smooth water would be ideal)? If the rpms do not change then the coil/powerpack is breaking down. If they do not change after pulling each of them one at a time then we will look for another cause.

 

[mstritt]

Re: Weak Spark=No Power?

I've tried this, but not under load, and when you pull each lead to the spark plug the RPM's decrease. <br />Thanks<br />Martin