johnson 115 ois year 2000

[tipperarypaddy]

starts fine and idles well
but misfires occasionally when you throttle up and under load
have changed fuel pump, plug leads and electronic distributor
fuel filter spotless

could it be the power pack?

 

[Chris1956]

It could be the carbs. What is an "electronic distributor"?

 

[tipperarypaddy]

its the sensor on top of engine; optical sensor I think its called.
what do you think could be wrong with the carbs?

 

[jakedaawg]

Check cover of vst for leak. If not then clean throttle body ports. Assuming you have changed plugs, compression and spark checked already

 

[tipperarypaddy]

is vst hard to find?

 

[racerone]

Test this motor with a timing light !----You need to find out if it is spark related or not.-----Hook up to each plug lead and go to full throttle out on the lake.---Observe the timing light behaviour.----This could be a lower unit issue as well.---Have you drained gear oil to inspect ?

 

[w2much]

Back to the original question. Yes . When the powerpack heats up it will cause a miss then eventually fail. Been there done that. Go to the CDI webpage it has a lot of good information.