Honda Outboard 15HP 4strokes Problem

[pepe67diver]

Hi folks,

I have a small problem with my outboard. It starts fine, when I put it in forward it engages fine, but as soon as I accelerate, it simply revs up without much happening at the propeller level. At its slowest speed it will push my inflatable forward, but as soon as I rev up…the engine sounds like it is revving up but the propeller seems to not respond…
Any suggestion at what may be wrong? and possible course to fix it?
Many Thanks.

Pépé

[a64pilot]

Assuming it has a rubber hub in the prop that acts like a shock absorber, it sounds as though this hub has spun, I think most modern outboards use the rubber hub, replaced the shear pin on older outboards.
If I'm right you need a new prop, hubs can be replaced on bigger, more expensive props, but on a little one I doubt it makes sense to do so,

[pepe67diver]

A64pilot, thanks so much for the insight. I will take the prop out tomorrow and check for this rubber hub you mentioned. Hopefully I can fix this myself.

[colemj]

Yes, this engine has a rubber hub prop and not a shear pin. The hub is certainly replaceable - we have had it done with ours. They cost ~$15 and can be pressed in in a couple of minutes. Any good prop shop will probably have hubs and can do it.

You will not be able to fix it yourself unless you have a hydraulic press and the correct hub insert. Don't be tempted to drill holes and put in screws - everyone thinks this will work and it always fails.

If you don't have a prop shop nearby, then you might be able to purchase the hub somewhere and any machine shop with a press can take the old one out and put the new one in.

Mark

[Cadence]

Originally Posted by pepe67diver

Hi folks,

I have a small problem with my outboard. It starts fine, when I put it in forward it engages fine, but as soon as I accelerate, it simply revs up without much happening at the propeller level. At its slowest speed it will push my inflatable forward, but as soon as I rev up…the engine sounds like it is revving up but the propeller seems to not respond…
Any suggestion at what may be wrong? and possible course to fix it?
Many Thanks.

Pépé

Sounds like a case of prop hub slippage. Is there a rubber bushing in that hub?

[a64pilot]

Whats a new prop cost? How bad is your old prop as in wear to the blades, chunks missing etc?

[colemj]

A second prop is a good idea regardless (they cost ~$65). My advice would be to buy another prop, rehub the current one and keep it as a spare.

Mark

[pepe67diver]

Thanks all for your replies. I am going to purchase a new prop as they are not too costly and rehab the old one and keep it as a spare. Will keep you posted on the results. Cheers

[pepe67diver]

Purchase a new prop for $200 and replaced it. Tested the engine and I am glad to report my problem is solved! Thanks all.

[colemj]

$200! Is that US$? Where are you located? I'm glad it worked out for you.

Mark

[a64pilot]

Wow, you did at least get dinner out of the deal didn't you?
Last time I bought a little prop it was for a 25 HP Mariner, I think I paid $50 or so for a Solas prop, I'm guessing you got a genuine Honda prop at least, maybe even SS?

[pepe67diver]

Yes, I was a little taken aback when I was asked to part with $200, but living in a small seaside town Dunsborough in Australia, I took it in my stride. Next time, I'll place an online order...

[colemj]

Well, look on the bright side, you only paid $177 USD and only 110 British pounds, and you have a working outboard again!

Mark