Spun hub?

[stocky]

I was out in the money bucket fitted with a mid 80's 150 hp V6 Mariner the other day. Anyway on one or two occasions when I applied some throttle there was a loss of power but no drop in revs and maybe a shuddering noise from the motor. The money bucket is a 20 ft fibreglass half cab which weighs approximately 850 kg (bare) and had a load of 4 adults and two children. Would the scenario represent the problem of a spun hub and how can I check if this is the case. Thank you.

 

[twwmm]

Re: Spun hub?

The rubber in hub if damaged will tend to let go under load like a slipping clutch. the motor will still rev but the prop wil slow down, sound like the problem. Have a good look in the ub you may be able to see if it is torn. See how the prop feels to turn by hand (make sure ign off)seee if it has a spongy feel. Take the prop to a dealer or mech they can check it for you. <br />Cheers

 

[Franki]

Re: Spun hub?

Hi Stocky....<br /><br />When I spun my hub, mine actually increased revs when the prop started slipping. which makes sense if you think about it, If you push the clutch in on your car while hooning down the street, your engine will rev its rings out.. this is a similiar sort of thing..<br /><br />are you sure it wasn't cavitation or similiar???<br /><br />did you have your motor tilted up more then usual that day??? or lots more weight up front then usual?<br /><br />just another 2 cents worth..<br /><br />rgds<br /><br />frank

 

[twwmm]

Re: Spun hub?

forgot about cavitation, this is where bubbles of air form around the blades, like lift it out of the water, can actually be steam. Usually ive seen this in high power tight turns

 

[stocky]

Re: Spun hub?

Thanks for the reply Franki-10072 and TWWMM. I am only new to this boating game and when anything occurs I tend to back off. In hindsight the revs did probably increase when momentum was lost. At the times this has occurred I had two adults in the rear seats and the motor well and truly trimmed in. In addition I dont tend to accelerate out of the hole like a bullet as I have two young kids on board and I try and make the whole process of accelerating and slowing down as smooth as possible. This is why I dodnt think it was cavitation. In addition on one occasion I was cruising along at approximately 35 kts when the problem occured and on that occasion there was a definite noise from the outboard. Again thanks to you both.

 

[twwmm]

Re: Spun hub?

ps the idea of the rubber is to let go if you hit something with the blade. The rubber will tear and stay torn, it is designed however to provide eneough grip to still run the prop and will usully let ago agin at high power. It should be repaired or replaced. Some people can actually repair the prop so don't be fooled that u must buy a new one. If you ddo get another prop keep the old one on board as a spare, along with a split pin, just incase you throw a blade. Uncommon but can happen, it will get u home