slipping honda 20hp outboard

[njamesphoto]

we have a 20hp outboard on our tender and today whilst well loaded the engine overrevd and now it will not go above 50% revs before it feels like a clutch is slipping. Looking online causes could be the rubber in the prop slipping after an impact or a clutch within the engine slipping. Its not cavitation as nothing else has changed. Any help please?

 

[Kawasaki]

Deffo sounds like the rubber bushing in the prop needs sorting
There is no clutch within the engine.If there was a prob or damage in the gearbox you would hear it and feel it!

 

[njamesphoto]

i have took the prop off and the bush looks intact, i have tries to twist the bush but it seems solid. I suppose it needs a lot of torque to make it slip. can the bush be replaced or is it just a new prop (4 bladed alloy at the moment)

 

[VicS]

i have took the prop off and the bush looks intact, i have tries to twist the bush but it seems solid. I suppose it needs a lot of torque to make it slip. can the bush be replaced or is it just a new prop (4 bladed alloy at the moment)

yes it needs a lot of torque
You can check the prop hub by scribing a line or marking a line with a water proof marker pen across the end of the prop shaft Put marks on the prop to line up with it.

Go for short thrash.

If the marks on the prop no longer line up with the line on the shaft you do indeed have a spun prop hub.
Of to the prop repairers with it.

The symptoms you describe are typical .

 

[Jamesuk]

I have the same symptoms. A guest took the tender then told me they got seaweed round the prop.

With similar symptoms: slow throttle and speed increases until pitch of engine is higher than usual, any more throttle and it's revving hard but no thrust.

Is this likely a result of the prob hitting a rock?

 

[landlockedpirate]

I have the same symptoms. A guest took the tender then told me they got seaweed round the prop.

With similar symptoms: slow throttle and speed increases until pitch of engine is higher than usual, any more throttle and it's revving hard but no thrust.

Is this likely a result of the prob hitting a rock?

Hitting a rock, seaweed wrapped round the prop, fishing line in the seals, running through sand or just simple fatigue. Lots of reasons why the it could have spun, easy fix, just send to Steel Developments for a next day repair.