Propeller spins in dirt, getting a spare

[molsenice]

Soo I have the boat running now thanks to all you folks and managed to land a 24" 7.75lb largemouth bass this week. Shortly there after, I spun the prop on the bottom in the sand and noticed some slight gouging and a small dent, not to mantion my heart rate going imediatly to about 400 beats per minute. No noticable performange change in the boat, guess I got reall lucky. The motor is a 1967 Mercury 95hp and the prop is two bladed. Many many years ago my pop looked into putting a three blade prop on the motor and was told by a very trusted marine mechanic that would be a mistake. My quastion is why? I have also been told by a friend that I can send this prop out to be refurbished.

 

[Laddies]

Re: Propeller spins in dirt, getting a spare

Todays three blade props are more efficient than the two blades of yester year there was a time when two blades were faster, but todays three blades are faster and develope more torque--Bob

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

any chance the reason my pop was warned to not put anything other than a two blade prop on the motor being a chance of the increased torque damaging a motor that old? I can not ask the mechanic as he pased away years ago, but I even remember as a kid how he reacted to the suggestion of a new three blade prop. Thanks for the reply by the way Bob

 

[Coolmaker]

Re: Propeller spins in dirt, getting a spare

"Todays three blade props are more efficient than the two blades of yester year there was a time when two blades were faster, but todays three blades are faster and develope more torque--Bob" <br /><br />Amen, I went to Mercury school in 1963 (Fond du Lac ), and it was common knowledge that a 2 bladed prop was thought to be the best, because of less drag through the water(factory techs). Then they realized that the extra blade did not add much drag and it did indeed add allot more thrust!! Imagine that!!! The two blades were never faster, just looked like it...and we thought because "they" said it, it must be true....

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

so is a tree blade going to hurt the motor? - I'm thinging torquing to hard on the gear box or twisting off a spline. If it won't hurt the engine then a three is the way to go isn't it?

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

One other thought, is there any chance of damage to the motor due to the slight gouging and small dent on the prop, as mentioned above, everything seems to be fine but i have heard it mentioned that props out of balance can do harm.

 

[Motor Boater Bill]

Re: Propeller spins in dirt, getting a spare

As far as strain on the motor, I would think pitch will be more critical than the number of blades.

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

Motor Boater Bill, thanks for the response, you helped me get this motor running back in June when I connected the batery backwards. Any suggestions for seleting a new prop, I think I notice some slight vibration at low speed last time I had the boat out. There is some obvious damage to the edge of the prop, but it looks minimal. Almost as if I took a rasp and scratched up the outer edge of the prop on one blade.

 

[Laddies]

Re: Propeller spins in dirt, getting a spare

A 3 blade with the same pitch as the 2 blade you have should work fine, you will have to get the right prop hareware to run the new style props--Bob

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

Prop hardware?? as in adapters? suggestions for best props and suppliers? or who to stay away from - thanks!

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

well had the boat out again and felt like I was being and "old wife" - I thought there was a slight shimmy in the motor as the main consoule and the boat never had a shake and now it did - so I thought and felt - luck me oh LUCKY ME!!! - turned around, docked and looked at prop. the lock tabs had come undone and the prop had at least 3/4" play in and out (it had worked it's way loose). Removed the prop, buffed out the rough edges withe emery and replaced, making sure all was good and tight. - Acts like new - lucky me. oh yeah - I wrote down the prop numbers so I could track down a spare - with my behavior - who knows.

 

[Triton II]

Re: Propeller spins in dirt, getting a spare

molsenice... your question regarding the wear and tear of a three-blader over a two-blader is a good one. It is my understanding that due to the individual prop blade surface area being smaller on a three-blader and the fact that the upgoing blades don't provide as much thrust as the down-going means the two-blader is harsher on the engine than a three-blader.

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

Triton II - thankyou - you have answered my question - Australia - wow - had a friend get me a Harly Davidson shirt shipped over here from there as a gift - someday my wife and I will make it there as a dream vacation.

 

[Triton II]

Re: Propeller spins in dirt, getting a spare

molsenice, Australia's a great place for living, loving and boating. That's why Aussies are generally a happy-go-lucky bunch - we live in the "lucky country". Hope your prop is still working OK, and if/when you need a replacement I would definitely go for three blades over two.

 

[molsenice]

Re: Propeller spins in dirt, getting a spare

Prop working awsome - time to go back to work through, won't get as much fishing in now that schools back in session - mabe quiting work all together is an option worth looking at - fishin is more fun.