The Most Costly Lobster Dinner of the Summer.....

secondcurve · 08-08-2012, 09:11 PM

Quote:

Originally Posted by Jonas Pilot

They're your boats. Do what you want. I am only trying to help.

Dave R is arguably the most knowledgable boater on this site. If he says you can run a slightly dinged prop as long as there is no vibration I'd go with his advice. I have listened to him many times in the past with excellent outcomes.

Jonas Pilot · 08-08-2012, 09:40 PM

What has he helped you with? If it has anything to do with props it will be beneficial to us all.

What if he is wrong. My advise will cost you nothing. Other's advise might cost you a lower unit.

secondcurve · 08-09-2012, 08:12 AM

Quote:

Originally Posted by Jonas Pilot

What has he helped you with? If it has anything to do with props it will be beneficial to us all.

What if he is wrong. My advise will cost you nothing. Other's advise might cost you a lower unit.

Take a few minutes and go through Dave R's historical advise and ask your boat mechanic about the prop question (I did) and you will see. You and I and many of the others on the board would likely switch a dinged prop as soon as possible. However, it's is inaccurate to tell someone that they are doing damage to the lower unit with a slightly dinged prop if no dedectable vibration is being dedected.

Belmont Resident · 08-10-2012, 05:53 AM

Quote:

Originally Posted by secondcurve

Dave R is arguably the most knowledgable boater on this site. If he says you can run a slightly dinged prop as long as there is no vibration I'd go with his advice. I have listened to him many times in the past with excellent outcomes.

Sometimes you site back and wish you said nothing and let Capt. ????? learn for themselves the hard way.

But if you honestly think that someone looking at a picture that shows only part of the damage can make an educated GUESS then I guess Dave R is a god. Granted Dave has had some excellent advice with respect to engine problems and boating matters but the cost to replace an outdrive is in excess of $2000.00 for a rebuilt unit. Do you really suggest someone who can afford a boat to begin with take a chance when they can have a part fixed for under $200.

I don't know for me it is a no brainer, fix the prop, but who am I, I have only been working on my own boats, cars, snowmobiles and ATV's for oh, 40 some years. I just don't offer advise on those subjects because if your wrong you get beat up bad on this forum.

My advise, run it as is, if it breaks then you'll know you should have fixed the prop. Let us know though because if the prop does damage to lower unit it should make for an I told you so and a good laugh for some of us!!!!

Dave R · 08-10-2012, 06:50 AM

If you have been boating a long time, chances are you know people that have hit rocks hard enough to shear huge chunks of a blades (or entire blades) off aluminum props without internally damaging the lower gear case or prop shaft on an Alpha drive. They just installed a new prop and kept boating. A gear case that can shrug off the violence of a hit like that is not going to be damaged by a fraction of an ounce (or even several ounces) of prop imbalance.

The big, tapered roller bearings that support the prop shaft can easily cope with unbalanced loads. Think about how unbalanced the loads are on a car wheel (that uses the same kind of bearings). There's probably 800 lbs or more of load pushing up on the bottom of the bearing on a typical car wheel, and -800 lbs at the top, when just rolling along straight and flat. Throw in some cornering, bumps, and braking and the loads can become huge. Those bearings usually last the lifetime of the car, even if they are neglected.

Put a brand-new new aluminum prop on a balance stand some time (I made one when I repaired and modified Alpha props years ago), they are rarely perfectly balanced. They don't need to be.

rgilfert · 08-10-2012, 06:41 PM

I want to thank everyone who took the time to offer their opinion & advice on the damage done to my propeller. When the smoke cleared....given that I live on an island and wouldn't be able to use the summer home if I did significant damage to the stern drive/etc i opted to take the cautious approach: today I had a new prop installed and sent out the damaged prop for repairs (so that I'll have a back up on board). Thanks again!

NoBozo · 08-10-2012, 07:28 PM

AGAIN: Looking at your picture....you have NOTHING to worry about. Dress up the prop with a file and enjoy. You don't need a new prop.

NB

Dave R · 08-11-2012, 08:23 AM

Peace of mind AND a spare prop are valuable. Glad you have both now.

08-10-2012, 06:41 PM	#6
rgilfert Senior Member Join Date: Mar 2012 Location: Bedford, NH / Rattlesnake Island Posts: 299 Thanks: 152 Thanked 227 Times in 57 Posts	Thanks to all for your opinion & advice!! I want to thank everyone who took the time to offer their opinion & advice on the damage done to my propeller. When the smoke cleared....given that I live on an island and wouldn't be able to use the summer home if I did significant damage to the stern drive/etc i opted to take the cautious approach: today I had a new prop installed and sent out the damaged prop for repairs (so that I'll have a back up on board). Thanks again!

08-08-2012, 09:40 PM	#2
Jonas Pilot Senior Member Join Date: Apr 2005 Location: Wolfeboro, New Hampshire is my home, 24-7-365 Posts: 1,686 Thanks: 1,047 Thanked 336 Times in 189 Posts	What has he helped you with? If it has anything to do with props it will be beneficial to us all. What if he is wrong. My advise will cost you nothing. Other's advise might cost you a lower unit.

The Following User Says Thank You to Jonas Pilot For This Useful Post:
Jidge (08-08-2012)

08-10-2012, 06:50 AM	#5
Dave R Senior Member Join Date: Jul 2004 Posts: 2,985 Thanks: 246 Thanked 744 Times in 444 Posts	If you have been boating a long time, chances are you know people that have hit rocks hard enough to shear huge chunks of a blades (or entire blades) off aluminum props without internally damaging the lower gear case or prop shaft on an Alpha drive. They just installed a new prop and kept boating. A gear case that can shrug off the violence of a hit like that is not going to be damaged by a fraction of an ounce (or even several ounces) of prop imbalance. The big, tapered roller bearings that support the prop shaft can easily cope with unbalanced loads. Think about how unbalanced the loads are on a car wheel (that uses the same kind of bearings). There's probably 800 lbs or more of load pushing up on the bottom of the bearing on a typical car wheel, and -800 lbs at the top, when just rolling along straight and flat. Throw in some cornering, bumps, and braking and the loads can become huge. Those bearings usually last the lifetime of the car, even if they are neglected. Put a brand-new new aluminum prop on a balance stand some time (I made one when I repaired and modified Alpha props years ago), they are rarely perfectly balanced. They don't need to be.

The Following 2 Users Say Thank You to Dave R For This Useful Post:
challmec (08-10-2012), secondcurve (08-10-2012)

08-10-2012, 07:28 PM	#7
NoBozo Senior Member Join Date: Jun 2008 Location: Portsmouth. RI Posts: 2,231 Thanks: 400 Thanked 460 Times in 308 Posts	AGAIN: Looking at your picture....you have NOTHING to worry about. Dress up the prop with a file and enjoy. You don't need a new prop. NB

08-11-2012, 08:23 AM	#8
Dave R Senior Member Join Date: Jul 2004 Posts: 2,985 Thanks: 246 Thanked 744 Times in 444 Posts	Peace of mind AND a spare prop are valuable. Glad you have both now.