Propellor and shaft size mismatch

[Jim Cate]

Matt, looking at all of that it seems that buying a new prop and selling the old one would involve less fiscal loss and FAR less angst and time spent in the refit.

And for the others considering Matt's dilemma, you might not know that he is planning to swap the engine and tranny as well as the prop, and the two boats involved are of similar size and displacement. Thus the concerns about prop/engine match are moot.

Jim

[GILow]

Jim,

The new prop option is not cheap, mainly because the chance of getting decent money for the old one is highly unlikely. I know it is practically new, but nobody else can be expected to believe that, so they’ll only want to pay a fraction of its value.

If I can do something clever here I stand to save a lot of money.

Of course, for some, being clever is breaking out the cheque book, and good luck to them. But that’s not how I work.

[GILow]

Originally Posted by Jim Cate

Matt, looking at all of that it seems that buying a new prop and selling the old one would involve less fiscal loss and FAR less angst and time spent in the refit.
…

Regarding job speed and general angst, if I can stick to the 1.25 inch prop shaft then the job is no slower or harder. The engineer can turn out the new prop shaft in his own time and I can install it as I would have in the usual way. I am replacing the prop shaft as a matter of course, as I do not trust a 40 year old shaft with an unknown maintenance history. Also, I want to fit a PSS in place of the old stuffing box and those bits of the existing shaft look a little tired.

[Uncle Bob]

Originally Posted by GILow

Regarding job speed and general angst, if I can stick to the 1.25 inch prop shaft then the job is no slower or harder. The engineer can turn out the new prop shaft in his own time and I can install it as I would have in the usual way. I am replacing the prop shaft as a matter of course, as I do not trust a 40 year old shaft with an unknown maintenance history. Also, I want to fit a PSS in place of the old stuffing box and those bits of the existing shaft look a little tired.

Matt, have you considered getting just a new hub from Kiwiprop and fitting the rest of your existing bits to it, or perhaps as others have said, finding someone that is desirous of a feathering prop and just happens to have a 1.5 inch shaft. There may just be someone out there, you never know.

[GILow]

Originally Posted by Uncle Bob

Matt, have you considered getting just a new hub from Kiwiprop and fitting the rest of your existing bits to it, or perhaps as others have said, finding someone that is desirous of a feathering prop and just happens to have a 1.5 inch shaft. There may just be someone out there, you never know.

Yep, I had a good chat to Kiwiprops about all that. In the end the hubs are about 90% of the prop cost and none of the inner bits were interchangeable.

And thinking about the buyer market, it’s actually a bit problematic. Logic says that any boat with a 1.5 inch prop shaft is going to have a pretty big donk, and generally the owners of such boats are either lugging around slow old tanks and wouldn’t give a fig about a feathering prop (actually, they’d be correctly worried about the performance hit under engine) OR they are in very large expensive modern boats and wouldn’t feel the need to dabble with cheap secondhand feathering props when there are much nicer shiny new bronze creations out there for them to spend big on.

The only reason I have the 1.5 inch version is that the Swanson was fitted with a 96 HP Nissan truck engine, which tuned out to be total overkill once I’d put the boat on a diet. Now the 50 HP with the Kiwiprop is ample and of course, that HP only needs a 1.25 inch shaft, or maybe only 1 inch. (Not sure about that.)

I note, for reference, that the Kelly Petersons seem to have come with a 1.25 inch shaft standard and that was matched to a 62 HP Perkins.

Anyway, I did a whole lot of homework on this one before asking the question. It boiled down to the kindest solution to my wallet is to somehow put the existing prop on the new 1.25 inch shaft. And Kiwiprops themselves are happy with that solution. They put me onto the bush to pack out the shaft, and that’s still on the menu. I’d just like to come up with something more clever if I can.

[Montanan]

Is your repowering compatible with the blade rotation of your 1.5" propeller?

Kiwi Prop Specifications

FYI:

K4 - Kiwiprops 4 Bladed Prices
US $ 2700 per unit plus US $ 150 freight / unit.

Additional blades are priced at US $ 110 each - no additional freight if delivered with the unit.

Blades ordered seperately are US $ 110 each.

[GILow]

Originally Posted by Montanan

Is your repowering compatible with the blade rotation of your 1.5" propeller?

Kiwi Prop Specifications

FYI:

K4 - Kiwiprops 4 Bladed Prices
US $ 2700 per unit plus US $ 150 freight / unit.

Additional blades are priced at US $ 110 each - no additional freight if delivered with the unit.

Blades ordered seperately are US $ 110 each.

All good, thanks.

[GILow]

Originally Posted by Montanan

Is your repowering compatible with the blade rotation of your 1.5" propeller?

Kiwi Prop Specifications

FYI:

K4 - Kiwiprops 4 Bladed Prices
US $ 2700 per unit plus US $ 150 freight / unit.

Additional blades are priced at US $ 110 each - no additional freight if delivered with the unit.

Blades ordered seperately are US $ 110 each.

Incidentally, that site is a subset of the main site. A U.S. reseller I assume.

Check out the main NZ site where the props are actually made for more comprehensive and up-to-date info.