What size motor (length/HP) for 81' 24' Offshore?

[jbrinch88]

Hey guys, new guy here looking for some information. I'm looking at an 81' 24' offshore tomorrow for myself. The boat is setup for a transom mounted outboard but has no motor. I asked about the transom/fuel tank covers etc and the owner claims the transom is solid still but the floor has a soft spot.

Doesn't surprise me at that age, but the seller is only asking 1400.00 for the boat which I feel is a great price for a project boat. The fuel tank is also brand new so I know that alone costs between 700-1000.

This isn't my first Grady, I currently have an 88 22' seafarer that I did a lot of work too and is up for sale. I also sold an 88' 20' overnighter last year at this time. However this boat I am keeping for myself and plan on putting a lot of work into assuming I can work with it.

My main question is what power will be good for this boat? I don't want the boat to be a hot rod but I've been on enough larger Grady Whites that were absolute pigs. A customer at the marina i work at has a 27' sailfish with a single 250hp yamaha and you have to run it pretty much wide open to keep it on plain. I figured either a 225-250hp would be plenty for this boat no? A 200hp I feel is borderline.

What shaft size is required for this boat? I would imagine a 25" shaft is what came on these?

I'm really excited to actually keep this one instead of just flipping it. I plan on spoiling it with some nice blue seas electrical parts and the usual offwhite starboard exterior overhaul to replace all the ugly teak. Thanks for any advice/information.

Jason

 

[family affair]

I would think grady would still have the specs for this boat, but the standards might have changed. Some things to consider:
- was the boat designed for twins?
- does the boat have or will you add a hard top?
- are you considering a 2 or 4 stroke?
- bottom paint?

Our boat tops out at 44 mph with a half tank, 2 adults, no bottom paint, and no hard top. You likely will not come close to those numbers with a 4 stroke 225.

If the boat was designed for twins, you could probably handle a single 4 stroke. 250 hp minimum to address all of the above considerations. A 225 2 stroke would probably get you close to the 250. Most of the newer grady hulls were designed to cruise between 28-30 mph. That also coincides with the most efficient operating rpm of modern outboards. A 200 etec could likely get you to that speed (without hard top, bottom paint), but you might need to run the engine close to WOT resulting in poor fuel economy.

Good luck!

 

[Doc Stressor]

Most of the Offshore 24s that you see around are powered by 225 hp 2-strokes. Some were sold with twin V-4 outboards, so the transom should not have a problem with the weight of a modern 4-stroke. I've seen several that have been repowered with 250 hp 4-strokes, both Yamhas and Suzukis. 250 hp is where you want to be with that hull. They take standard 25" shaft engines which are usually mounted at the second hole.

 

[jbrinch88]

Thanks for the information guys. The boat was setup for a single outboard. I just got back from looking at it trailer empty unfortunately. The boat needed a lot of glass work to look good to my standards. Also it looked like it may have been a salvage boat from Sandy that someone just tried to halfass make it look sellable. The hardtop was gone and lots of things missing (switch panels etc) not that it matters as I am looking for a project, but I wouldn't mind spending a bit more on a better package to work with.

So the search continues.

Jason.