Power loss

[jimbomitch]

Hi everyone, this is my first post, so I hope I am doing it right. I have a 1984 65hp Johnson that will start first time every time,will empty a test drum in seconds when forward gear is engaged, but as soon as the boat goes on to water I only get about 4 knots. Any advice would be much appreciated.

[boats.net]

Run a compression test, check that all cylinders are firing, may need to remove and clean carbs.

[jimbomitch]

power loss

Thank you kindly for the information. I will try that before a strip down and rebuild.