What Kind of Prop Is this ?

[flatlander]

Some background:
I was going to sail south for the winter, but when I arrived at the boat and started the engine (for which I had to overcome some unexpected obstacles), I put the engine in gear, and nothing. Upon pulling the boat, this is what I found: The photo of the bracket with no blades is my boat. The other photo is another boat that's in the yard. (Unfortunately I wasn't able to speak to the owner). This is the first time I've had the boat pulled since I've owned it, so I'm not sure what type of prop this is, or the more important question:

IS IT POSSIBLE TO BUY REPLACEMENT BLADES?

[Adelie]

Have you had a diver check under the berth for the blades or do you think somebody might have stolen them?

[flatlander]

It was on a mooring, so it would be a pretty large circle to check, and unfortunately the mooring has since been pulled, so I wouldn't even know where to start now.

[sailstoo]

It's hard to tell for sure w/o seeing the blades but I think it's a Martec. Suggest you contact and send your picture to them. They were extremely helpful last year when they rebuilt one of their folding props for me. You can contact them at Martec Sailboat Propellers

[Blue Stocking]

It begs the question, how did you get to the dock?. You haven't used the boat in the time you have owned it?

[flatlander]

No, I definitely have used it. It was on a mooring, I took a launch to the boat when I wanted to use it. The marina towed it to the dock for the haul out.

[Marksman]

I'll about gurantee it's a Martec. This is the Martec that I took off of my boat when I bought it.

[zeehag]

if you have dive gear and isnt too deep at the place where your mooring was, try to dive it and see if the pieces are there...... is toobad there arent prop locks the way cars have wheel locks.....

[senormechanico]

Imho, you would do better to just replace it with a Flexofold.
Gear driven folders are newer design and superior to the old Martec.

[fstbttms]

Originally Posted by flatlander

IS IT POSSIBLE TO BUY REPLACEMENT BLADES?

Yes.

Originally Posted by Marksman

I'll about gurantee it's a Martec. This is the Martec that I took off of my boat when I bought it.

There is no doubt that it is a Martec. They are the only folder that uses cotter pins to secure the nut and pivots.

Originally Posted by senormechanico

Imho, you would do better to just replace it with a Flexofold.
Gear driven folders are newer design and superior to the old Martec.

Martec has a geared folder:

http://www.martec-props.com/pdf_file...g_brochure.PDF

[Marksman]

I don't think you would find the blades if you went looking as it looks to me that someone pinched them. The Martec uses monel pivot pin and cotter pins which are not going to corrode away, and you will notice the heads are still in the hub. So I think the pivot pin was simply driven out and the blades absconded with.

[delmarrey]

I have this SS Slipstream (for sale) that replaced the old Matrec, which I still have.

Now I have a larger shaft (1-1/8" w/a Maxprop) so can not use either one of them, which were for a 1" shaft.

Unfortunately, the diameter and pitch are marked on the blade hubs, so that will have to be calculated out before you can get a replacement.

So, what motor and gear box ratio do you have???

And, how far is the end of the shaft from the hull???

And displacement of the boat???

[fstbttms]

Originally Posted by Marksman

So I think the pivot pin was simply driven out and the blades absconded with.

You think somebody went to the trouble and effort of driving the pivot pin out past the cotter pins rather than simply pulling the cotter pins out?

[Marksman]

I know, it doesn't make sense, but I can't think of any other way the blades could have dissapeared. Unless the origianal monel pin had been replaced at some time with a less noble metal and it simply dissolved away. A close examination of the hub would be more telling. When I removed my Martec, the cotter pin holding the shaft nut would not come out, so after struggling through a half tank of air I forced the nut rotation and sheared the cotter pin. Was surprisingly easy, hence my suggested theory.

[delmarrey]

The reason I replaced my Martec was that it got so sloppy that it rattled when motoring. And, one blade would get stuck sometimes causing a hellOfa vibration.

I'll bet that one of the the cotter pins that holds the monel pin in place just wore out, allowing it to fall out.