lambertfam
Seaman Apprentice
- Joined
- Jul 24, 2008
- Messages
- 38
I have an old 1967 20HP Johnson and I would like to verify the RPM at the impeller but I have no idea how to do that. I am new to boating so I was wondering if there is a tool or gauge that can be connected to the motor that can measure this while it's in the water. It is a simple tiller arm control.