Looking at a 2001 22' Twin Vee with twin Johnson 70 EFI 4 stroke motors. Not too familiar with Johnsons. Running a Honda 90 now.
Its from long shaft when not under load drive shaft rattles . put grease on drive shaft splines. Nothing is wrong with motor.Reason rattles goes away
I have had it tested and they confirmed that the compression was ok. They tested all four cylinder and they were within %10 of each other
Agree with Joe. What is the compression on it ?? You can't tune a motor with poor compression.
If out of round yes....