Piece of WOOD WEDGED IN PROP - Did I break my motor???

[dajohnson53]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

I just can't figure out why people think an aluminum prop would be safer for the lower unit than a SS one. My understanding is that the rubber hub is designed to give way at a certain level of shock before the lower unit is damaged. It will give way under the same stress whether the prop is made of SS or aluminum. The metal of the prop is not a factor in damaging the lower unit, unless you're saying that all these props have a rubber hub that is not properly designed to protect the L/U, and therefore the metal of the prop itself is? Just mho of course, but that's what the rubber hub is for and I can't see why it would give way any harder (and thus cause damage) for a SS prop than an aluminum one.<br /><br />I'm hoping someone who knows about this subject will correct me if I'm wrong.

 

[CATransplant]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

I know what would have happened with my geriatric 35hp RDS-20. It would have sheared the shear pin when it grabbed that stick. I've had it happen already a couple of times with a rock. No real damage to the prop, either, and it's a standard aluminum prop.<br /><br />Sometimes I wonder if the old shear pin drive wasn't pretty good. Less than 5 minutes to change it out, even on the water, although I prefer to do it on land.

 

[rdgallo]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

Butteco, I hope your boss doesn't read this forum!! He might be even a little tighter than you think. LOL

 

[tommays]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

i can say from doing it you can fold a blade on an alum prop at a crazy angle hitting something and the HUB shows no sign of failing<br /><br />the hubs seem to fail more from high torque then hitting things<br /><br />you have the same prop hub on motors from 135 to 300 hp so i think it really just helps dampen vibration<br /><br />how could one that takes 300 hp ever fail on a motor 1/3 the size <br /><br /><br />tommays

 

[Scali]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

No way anything happened, that aluminum prop wouldve bent into a pretzel before any damage would take place even then I bet no damage would occur to the motor...<br />I cant tell you how many times I'v had bags wrap around my prop stalling the motor.<br />Also, it's a good argument for aluminim props over stainless, I learned my lesson with a SS prop taking out a LU on my 3 week old Johnson 90 a few years ago when I hit a slab of cement ..

 

[BillP]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

Originally posted by Scali:<br /> No way anything happened, that aluminum prop wouldve bent into a pretzel before any damage would take place even then I bet no damage would occur to the motor...<br />I cant tell you how many times I'v had bags wrap around my prop stalling the motor.<br />Also, it's a good argument for aluminim props over stainless, I learned my lesson with a SS prop taking out a LU on my 3 week old Johnson 90 a few years ago when I hit a slab of cement ..

Ditto on the aluminum prop. It takes hardly anything to curl an aluminum prop and that prop still looks A1. If the hub didn't spin I doubt there is damage anywhere.

 

[butteco]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

well that settles my nerves a lot!<br /><br />I don't know if any of you have been following my previous posts, but I had been searching and searching for a good runabout/ski boat and finally found this little speed/ski boat! I paid $1900 for it with an 85hp 1976 Evinrude out back. I am a college student so that $1900 maxed my out funds wise! I was really worried that that log could of damaged my motor or lower unit and rendered my boat USELESS!!! <br /><br />I think I will stay away from that lake and hang out at the afterbay where they release water from the main lake, but it is screend (no wood floats through) the water is MUCH colder in the afterbay, but I won't have to worry about logs!!!<br /><br />thanks!

 

[Scali]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

stay away from lakes in general, hit the salt & corrode your motor like the rest of us !

 

[butteco]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

ha

 

[Jilly - 5]

Re: Piece of WOOD WEDGED IN PROP - Did I break my motor???

On ss-induced LU damage vs alum damage:<br /><br />Somebody above was on point when he said hub rubber is designed for "slow-release" breakaway (like under heavy load) rather than sharp impact break-away. Under prop impact severe enough to chip LU gear teeth edges, the ss delivers unmitigated impact directly to the LU gears and splines of the vertical shaft. An Al prop will bend/fracture under an impact severe enough that it would chip gear teeth. Stay Al, ss is for big offshore efficiency.