Dings in prop?

Stoo · 15 April 2007, 04:53

I have developed a few minor "dings" in my s/s prop from occasionally using it as a depth sounder. Do you think they make much difference to the performance of the boat? (Engine is a 150 Yamaha)

Is it reasonable to just grind them out, or should I send the prop into a "pro" for repair...?

BogMonster · 15 April 2007, 12:47

I'd get it fixed properly. I got a new 19" pitch for my engine and was up to 39kts with much improvement of the cavitation problems. I proceeded to smack it on something (not the bottom, I think I hit something in the water) and chipped the leading edge and I'm beginning to think that's where my missing 3-4kts is and its definitely made a difference to the cavitation when turning, its much worse than it was when the prop was in perfect condition.

If it was practical to get a prop repaired here I would, but I guess it will have to be another new one

Would never have thought relatively minor leading edge damage would make that much difference but it seems to.

jyasaki · 16 April 2007, 17:10

I'd be a little leery about grinding them out. You'll change the balance more on a SS prop, as the metal is heavier than aluminum. The differences in blade thinckness at the ground sections probably won't do you much good, either.

A prop reconditioning that doesn't require much welding should be less than $100 or so, as I recall. Not too bad when you consider a brand new SS prop will upwards of about $250.

jky

pathalla · 21 April 2007, 02:53

Stoo, I have never much messed with prop dings/bends or damage... always took it to the prop guy. I recently discovered that if you use a block of wood on one side of the blade and a hammer on the other it is surprising how easy small dings are straightened out. Hold the block tightly against the blade and start out gingerly hammering the bent portion of the prop, watch the results. IF it is aluminum, if stainless, take it in.

Limey Linda · 21 April 2007, 03:14

Quote:

Originally Posted by pathalla

Stoo, I have never much messed with prop dings/bends or damage... always took it to the prop guy. I recently discovered that if you use a block of wood on one side of the blade and a hammer on the other it is surprising how easy small dings are straightened out. Hold the block tightly against the blade and start out gingerly hammering the bent portion of the prop, watch the results.

That is a good fix for minor dings. However , I prefer to use a tightly packed sandbag ( or a bag of #7-8 lead shot)with a piece of leather over it. This supports the shape of the blade.
Lots' of small taps with the the ball end of a ball pein hammer and file/sand to finish. Take it slow.

pathalla · 21 April 2007, 03:44

Quote:

Originally Posted by Limey Linda

That is a good fix for minor dings. However , I prefer to use a tightly packed sandbag ( or a bag of #7-8 lead shot)with a piece of leather over it. This supports the shape of the blade.
Lots' of small taps with the the ball end of a ball pein hammer and file/sand to finish. Take it slow.

Thanks for that Limey, I will try that the next time I ding a prop, shouldn't be too long...

Stoo · 21 April 2007, 22:50

Decided to fark the prop... Finally got out on the lake and in for a dive today!

Water temp is a baulmy 36 up top and 34 at 100'... Just like Little Cayman give or take 45 degrees or so!

The trusty boat fired up like a charm. We spent a little like with the Coasties in there 733. They were breaking in a new crew, so just out burning tax-payer supplied fuel...

Sorry... no pics today. Lent the camera to a friend...

Have you dug out yet Pat?

simmons0 · 22 April 2007, 01:17

Quote:

Originally Posted by Stoo

I have developed a few minor "dings" in my s/s prop from occasionally using it as a depth sounder. Do you think they make much difference to the performance of the boat? (Engine is a 150 Yamaha)

Is it reasonable to just grind them out, or should I send the prop into a "pro" for repair...?

I don't think anyone has pointed it out, but thats not a s/s one, so pretty cheap to replace.

pathalla · 22 April 2007, 01:57

Quote:

Originally Posted by simmons0

I don't think anyone has pointed it out, but thats not a s/s one, so pretty cheap to replace.

Don't know about that, Yamaha also makes black stainless props, can't remember what they coat them with...

Stoo · 22 April 2007, 01:59

Actually it is stainless. I have no idea why it's black (mostly)....

captnjack · 15 May 2007, 19:45

There's alot of pitting on that prop. Do you have a clean flow of water to the blades? Correct pitch? Maybe the blade's bent and the pitting is secondary to that damage. I think it needs professional service, possibly replacement.

Stoo · 15 May 2007, 21:10

Quote:

Originally Posted by captnjack

I think it needs professional service, possibly replacement.

Funny... That's what my ex said about ME! I will get a pro to look at it Cap... It's on an extra freekin' long staft as is, so I don't think I can get it any lower in the water! It could have a wee bend I suppose. Like I said, I use it for a bottom sounder now and again...

Thanks for the tips...

Biggles · 15 May 2007, 21:38

Stoo,

That prop would be on the 'To replace List'

I know its a lot of money to keep replacing props but look upon it as buying a spare. Keep that knackered old one as a spare for emergencies and buy a nice new shiny one maybe of a different pitch if you like, to use now.

Then having done that stop bumping along the bottom.

By the way have you seen my prop. Second time out from new my mate took it through a mud bank. I wasn't too impressed but what can you say. I'm supposed to be the Skipper so it all boils down to me. Thats the last time I listen to a so called Proffesional RIB driver.

Stoo · 15 May 2007, 22:29

Well, I got 10 years out of it so I suppose I can't complain. We don't have mud on the bottom here... it's good old limestone, and somewhat unforgiving!

I really don't have much excuse for whacking the bottom. You can typically see at least 20 feet down here, although in my defense, my best "whack" was in the St. Lawrence River. It's very dark water there... That's my story and I'm sticking to it...

The thing with using your boat as a wreck diving platform, is that you're typically visiting areas that sunk a ship already. Maybe I should take up fishing.

I just called up my local dealer...

Does anybody have any thoughts on factory props vs aftermarket? There's about a $400 spread between the two...

pathalla · 16 May 2007, 02:46

Quote:

Originally Posted by Stoo

Well, I got 10 years out of it so I suppose I can't complain. We don't have mud on the bottom here... it's good old limestone, and somewhat unforgiving!

I really don't have much excuse for whacking the bottom. You can typically see at least 20 feet down here, although in my defense, my best "whack" was in the St. Lawrence River. It's very dark water there... That's my story and I'm sticking to it...

The thing with using your boat as a wreck diving platform, is that you're typically visiting areas that sunk a ship already. Maybe I should take up fishing.

I just called up my local dealer...

Does anybody have any thoughts on factory props vs aftermarket? There's about a $400 spread between the two...

I have thoughts... Ebay.... next fall....

Stoo · 16 May 2007, 13:43

Quote:

Originally Posted by pathalla

I have thoughts... Ebay.... next fall....

You're not using your props at the moment... Maybe I could borrow one until you're back on the water???

I was reading another thread about testing different props. How the heck do you do this? I can't imagine my dealer "lending" me 3 or 4 different ones to try out before I buy...

pathalla · 17 May 2007, 01:02

Quote:

Originally Posted by Stoo

You're not using your props at the moment... Maybe I could borrow one until you're back on the water???

I was reading another thread about testing different props. How the heck do you do this? I can't imagine my dealer "lending" me 3 or 4 different ones to try out before I buy...

Borrowing a prop? No problem. You might want to do so assuming MY props are in better condition than yours, that of course may not be the case. Sadly I also live in an area rampant with limestone and I already have tested them to see if they are the "New improved" ding proof models... they aren't...
A good place to get a handle on what prop may be best for your boat is Yamahas website. They have performance bulletins with a variety of craft using different props. You can also call them, tell them you have a Yamaha and need some info on propping it correctly.

Stoo · 22 May 2007, 13:07

Thanks Pat... I pulled the prop yesterday and I'll pop into a Yammy dealer today. Apparently he has some no name brands there which require a hub adapter of some sort. I'll look at repair and replace, but I suspect the repair wait is significant this time of year, so that might be a problem.

I'll see if I can locate the Yamaha info as well...

Biggles · 22 May 2007, 13:25

Stoo,

I use a prop with a hub kit and its better than the original. Far better. So don't worry too much about lack of quality.

NR.

Stoo · 22 May 2007, 13:35

Quote:

Originally Posted by Biggles

Stoo,

I use a prop with a hub kit and its better than the original. Far better. So don't worry too much about lack of quality.

NR.

Good to know Biggles. I did have concerns about that...