2001 Johnson 90 stutters at high speed

[Sixmark]

Re: 2001 Johnson 90 stutters at high speed

Update -
Bad power pack. New one installed and ran boat for 20 minutes. No problems!

I don't particularly understand why it would stutter at high speeds and idle and cruise below 4000rpms fine but at least its fixed now.

Thanks to all for advice and suggestions!

Think of it this way, it's suppose to say when and how much spark your motor needs, at higher RPM's a motor requires more than it does at idle, kind of like the electric company having to provide more power on hot days. Anyhow over time and after being subjected to several heat/cool down cycles the power pack can lose it's ability to keep pace and stmbles.


A rule of thumb that I have used is the majority of high RPM issues tend to be spark/ignition related and the majority of low RPM issues tend to be carb/fuel related.