Clutch slipping? - Volvo B20 mid-mounted engine

While cruising I have noticed that every 5 minutes or so I lose power to the prop. The immediate effect is a sudden slowing of the boat accompanied by a change in noise to a higher pitched whirring.

The boat is new to me but the previous owner had looked into it and tells me it's a problem with the clutch. He said he thought it was loose.

I have a 7m cabin boat with a Volvo Penta B20. The engine is mounted in the middle of the boat, drive train about 2m, running under the boards to the prop.

Has anyone experienced a similar fault? Is the clutch the likely cause?

.... or a sheared or missing key on the prop. Which transmission? Have you checked the fluid level and color?? ( and smell)

You most likely have a MS3 or MS4 transmission.
The cone clutch's sliding sleeve and corresponding gear cups are the same as the early AQ series stern drives.
These seldom slip once engaged!


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