Prop Change

[terryjoe]

I recently had someone dive on my boat to clean the hull. He told me that one of the blades on my prop looked as if it were bent slightly. I have been having problems lately with vibrations.

I have two questions:

Can the prop be changed while the boat is in the water?
What would be a good prop to get for a replacement that isnt too expensive?

Thanks!

Terry

[Warren M.]

You have a number of options, but all would require your boat to be hauled. You could then pull your prop and have it reconditioned by a qualified prop shop if it is not in really bad condition. They can tell you that. I would explore that first as new props are expensive. But removing a prop can be a difficult chore and one that could require a prop puller -- a device your could either make or borrow. The current edition of "Good Old Boat" has an excellent article on Cutless bearing replacement and details how to make a cutless/propeller removal tool. If your prop is not worth reconditioning, another option is try to find a similar one (blade length and pitch are critically important) at either a consignment store or on eBay. If you buy a used prop, be sure you can return it if it turns out to either in poor condition or doesn't match up with your shaft/engine correctly. The wrong size prop can really overtax your engine. Good luck with this.

[Fstbttms]

Originally Posted by terryjoe

Can the prop be changed while the boat is in the water?

Yes. A knowlegable hull cleaner with the proper tools will have little difficulty pulling and reinstalling your prop. It may very well be that your existing prop can be repaired. Look for a prop shop near you for advice. If it turns out you want to replace it, used props can be found at some prop shops or on craigslist or ebay.

In any event, if all you need done is prop work, there is no need to haul the boat.

[Karletto]

i heard some people just lift the stern up so the propeller is above the waterline. is this true?

[Gary1]

Fastbottoms is absolutely right. Popping the prop on a sailboat is not a big deal underwater--if you have the right tools.

As to buying a new one, wait until you have a look at the old one. If all you did was curl the ends or something, a good prop shop can fix you right up, and for a lot less money than a new prop.

[Fstbttms]

Originally Posted by Karletto

i heard some people just lift the stern up so the propeller is above the waterline. is this true?

Is it true that you heard this? I'm sure it is.

Is it true that some people do this to change a prop? No.

[KeelHaulin]

Originally Posted by Karletto

i heard some people just lift the stern up so the propeller is above the waterline. is this true?

You might be thinking of a boat hoist called a "Hydro-Hoist" which is a boat cradle mounted on two pontoons. The flooded pontoons are filled with air to lift the boat out. Power-boat owners use them to dry store their boats in the slip so that they have the convenience of a slip and the dry storage so bottom cleaning, zincs and outdrive corrosion is minimized. I don't think you could use a Hydro-Hoist on a sailboat because of the deep draft at the keel; higher displacements and stability when hoisted due to standing rigging, etc.

[trantor12020]

With advise/instructions from fstbttm and some others here, I changed my prop under water, not once but twice with ease. The key tool is a 3ft length of 2x4 to wedge between the prop, P-bracket and shaft (do not use the engine gear to hold the prop), large hammer, 1_1/4" spanner(for prop nut) and 2- or 3- pronge cheapo bearing extractor(with suitable spanner). Tie everything with cord else it goes to davis jones' locker. You have to use scuba for the job.

[Fstbttms]

Originally Posted by KeelHaulin

I don't think you could use a Hydro-Hoist on a sailboat because of the deep draft at the keel; higher displacements and stability when hoisted due to standing rigging, etc.

I know a Merit 25 that lives on a Hydro Hoist. The guy puts garbage bags over the bottom of the rudder and keel to keep those parts clean, since they stay immersed. Seems like a real PITA.

But you're right, I doubt if any sailboat much bigger could be put on it.