Suggestions for an outboard motor for a 1978 "Duke 175"

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Lovetorestore

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Good day, everyone. I am new to this forum, and I'm hoping everyone here with years of experience with GW's can offer insight. I am being given a Grady-White model 175 Duke, a circa 1978 (discontinued model). It is in need of major cosmetic (and I'm sure mechanical) restoration. I am looking forward to to this project; as a professional art conservator it will be a fantastic conservation project I'll actually be able to use for fishing and general recreation in Maine. The first order of business: the boat does not have the outboard motor. After researching the Grady-White archives it appears the original motor was an Evinrude. Today GW uses Yamaha outboards exclusively. The label on the boat states 125 hp max.

I cannot seem to get in contact with Grady-White directly for suggestions. Any insight and suggestions for a substitute would be greatly appreciated. My brother owns a Parker with a 100 hp Yamaha, and it runs great. I thought considering a 100 hp Yamaha would be a good start.

Thank you all in advance.
 
It appears as though your maximum horsepower rating is going to be 125 hp for your vessel, of which in terms of a "legality" or "insurance" reason, the highest you "should" go up to would be a 115 hp outboard. Now, you could likely always go up a bit and I don't think that the Earth will suddenly stop spinning or anything. I personally think your best bet would be either a 115/140 hp Suzuki for a few different reasons. The first would be the warranty in that Suzuki has the longest warranty out there, being 7 years in length. The second would be Honda with a 5 year warranty, then Yamaha and Mercury with only 3 year warranties. The Suzuki 115/140 also come with an available digital/fly by wire throttle option, of which neither Yamaha or Mercury offer for that size of an outboard. Honda does on their 115, but the weight imo isn't worth the tradeoff. Which would bring me to the last topic, and that would be the weight of the outboard. Mercury's 115 hp outboard weighs the least at 363 lbs, then the Yamaha F115 at 386 lbs, followed by the Suzuki 115/140 at 423/428 lbs depending on if you get mechanical or digital controls. Lastly, the Honda 115 is the heaviest of all, with a dry weight of just under 500 lbs, specifically 493 lbs. Imo, it really just depends on what you want to do, what kind of features you'd like to have, if you want the lightest weighing outboard, if you want digital/drive by wire controls, how long you plan on keeping the boat in regards to the warranty, how much your budget is, etc. Of which I almost imagine that the Suzuki will likely be the least expensive out of the above options, or maybe just behind Mercury and might be in second place if you went with the digital controls. I would see what local dealerships are available nearby, look at their reputation/reviews and so forth as well as get back to us on some of the above mentioned items/preferences, etc. As mentioned above, I think that the Suzuki 115/140 would be my preference for the above reasons and because the weights between the two of them are the same... so I guess if the weight is the same, why not get an extra 25 hp on top of it?
 
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If you could post some photos, a lot of members here could chime in with relevant advice on your restoration project. Good luck with the undertaking!
 
Where 'bouts in Maine?

Grady won't be able to tell you aything different than what you've already found regarding the 125HP. There not going to state anything that could come back and bite them. CYA stuff, you know?

The first thing to focus on is the integrity of the boat - transom, floor, stringers, wiring etc. Once that is sorted, THEN you can get on to tertiary things like the engine.

Don't worry about what brand you see most Grady's with - it makes no difference in the end. All engines nowadays are good. Go with the brand that allows you easy access to servicing dealers and parts. Most likely, you'll find Merc and Yamaha top of that list.

Double check me on this, but I'll think you'll find your options to be 90HP, 115HP, 150HP. A little boat like that will be MORE than fine with a 90HP on it. But you may find that a 115HP is not much more - possibly less than a $1K.

You could, of course, rebuild the boat as stout as you want and easily support a 150HP - but there's really no reason to do that when the other engines will work so well.
 
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WOW! I didn't expect such a speedy response! Thank you, thank you! This is great advice. I'll be towing this boat from suburban New York to the mid-coast Maine region, where there is no shortage of marinas, boat builders, boat repair facilities, boat salvage operations, yadda yadda.... so if the project ends up being non-viable, I can always recycle it for parts, etc. From what I can see (and I am no boat expert) it looks to be in very good structural shape, despite its appearance. But I will be able to have a professional give it a once-over for an assessment. In the meantime, I'll try to post a few pictures, but please be sitting down when you see them. I suspect most of you will say "he's gotta be kidding..." but as I said, I think most of it is cosmetic but clearly needing new wires, cables, mechanicals, etc. I took a painting that was given up for dead from Hurricane Katrina, received from a Louisiana art gallery, and was able to save it. Lots of TLC required. This boat is my next Hurricane Katrina (possible name....?)

Thank you, Mustang65fbk, for your response and advice, and HTHM, I'll try to get some pictures up asap.

Phil
 
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Thanks, DennisG01. I am in Waldo-Knox County, Maine, encompassing Rockland up to Searsport, and everything in-between. Many storied shipbuilding/repair coastal town operations to choose from. Most of them specialize in high-end yachts or vintage wooden boat restorations, but I think I'll be able to convince someone to take on my after-thought project, even if it's out of pity. I'm not going to try to turn a Duke into a cigarette boat, so any motor that's good for trolling for mackerel or just bopping around will be fine. Thanks for your reply and advice.
 
Some elbow grease (well, a LOT of elbow grease) and replacing cables....... the transom is 20 and 3/4 inches, so I think a 20 inch shaft for a new outboard would be fine.... I think.....
 
The 2 x 4 boards you see is a frame the previous owner constructed to tarp the boat, which has since blown off.
 
The last boater registration tag on there appears to be from 2007 and expiring in 2008, or at least that's how they do it in Washington state, but it's definitely been sitting for almost 20 years. Of which, I'm hoping the gasoline wasn't left in it throughout that time? If so, and probably even in general, I'd replace the fuel tank, fuel lines and everything else that hasn't been operated or used in the last almost 20 years. Same goes for everything on the trailer... tires, brakes, bearings, axles. How squishy is the floor to stand on? I imagine if wet leaves have been sitting on it for almost two decades that it'll need some work at the very minimum. To me, it depends on how much time, effort and most importantly money you want to sink into this boat. A brand new outboard is likely going to be $8k-$10k and that's before you buy/do anything else to the boat. I imagine after all the money you invest, you're likely going to be into the boat at least $15k-$20k, if not maybe even more, depending on the actual condition of the boat. If the transom needs to be replaced, that could be $8k-$10k by itself. If you're doing this for a fun project and don't care about how much money you spend, or it's a sentimental thing, then sure continue on with it. If you're doing this to keep the boat for a few years, then maybe sell it and see if you can break even? I don't imagine you're going to get anywhere near the money back that you put into it. Just my opinion of course, good luck with whatever you decide on doing.
 
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I would have to replace all the innards....fuel tank, lines, bilge pump, cables, etc. It was covered for years, I think the cover blew off only the past 4-5, and there is no accumulated water, and the floor is solid. I walked around on it and did not detect and "give." The trailer will need two new tires, greased bearings, etc. If it isn't road-worthy I would borrow/purchase/rent/steal/pilfer one to use.
 
I'm VERY familier with your area... it's my area, too :) It's my second home area - and family has been there for about 100 years. I'm in Friendship (on an island) and Cushing.

To your point about some high end local builders... um, yeah, don't even step foot in Lyman-Morse :) Wonderful place, though - very friendly people there. But I can barely afford the charge to clean up my drool when going there ;)

It looks like you have a fun project ahead of you and it seems as though you're in the right mind-set for it.

FYI... look around for usesd engines. It's not uncommon to find something in your HP range in the sub $4K range and it will still be a solid engine. There's a good percentage of people that replace engines "just because". Which, really isn't all that hard to understand since lot's of people buy a new car every 3 to 5 years.

You probably have an aluminum tank in there? Go plastic. Cheaper and better. Plus, you're probably looking at 50g max... maybe smaller. And they are readily available/easy to find.

If the floor REALLY is solid... wow! In that case, a suggestion... is it carpeted? Strip it down and paint with a good non-skid paint. There's absolutely no reason to use gelcoat when paint is easy and good. I used Pettit EasyPoxy non-skid on my boat and am very happy with it.
 
I agree with 90hp being a realistic option for that boat. Cheaper and lighter. Take a look at tohatsu if you look new
 
Right now it's a contest between Tohatsu (thank you for the suggestion PointedRose), Yamaha, and Suzuki, but I'm going to lean towards whoever is most available to service it, so taking into account fuel efficiency, price, and weight it's looking like Suzuki. The tank is definitely aluminum and will have to be replaced, along with most of the other mechanicals. The carpet will have to be stripped also, and hopefully there won't be any major surprises: fingers crossed. I seriously doubt Lyman-Morse in Camden, Front Street Shipyard in Belfast, or any of those places would let me walk through the front door without a credit check. My family has been summering there since the 1930's, and I'm very friendly with most of the lobster boat owners who I'm sure will point me in the right direction once I get the boat up there. Throw in Hamilton Marine and I think I'm pretty well covered.

So DennisG01, sounds like you can see the Olson House from your back porch!
 
Are you wanting an outboard with a digital/drive by wire throttle, or are you just wanting to stick with mechanical? The Tohatsu 90/115 is also almost 400 lbs, of which you mentioned that you thought you could use a 20" shaft version of the outboard, and the Suzuki 90 is only 344 lbs for their 20" shaft. I'm thinking that might be your first choice right there, unless you wanted something with digital/fly by wire controls, of which their 115 in the 20" shaft is 419 lbs.
 
No, I'm not going digital. I need my 10 year old niece to program the microwave oven, let alone deal with electronics with motherboards and other ready-to-fail workings. Definitely staying with mechanical, and the lighter weight Suzuki 90 is most likely the winner. And to JeffN's point, yes, brand-dealer-service is also a top priority, and both Yamaha and Suzuki check those boxes.
 
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Lovetorestore said:
Right now it's a contest between Tohatsu (thank you for the suggestion PointedRose), Yamaha, and Suzuki, but I'm going to lean towards whoever is most available to service it, so taking into account fuel efficiency, price, and weight it's looking like Suzuki. The tank is definitely aluminum and will have to be replaced, along with most of the other mechanicals. The carpet will have to be stripped also, and hopefully there won't be any major surprises: fingers crossed. I seriously doubt Lyman-Morse in Camden, Front Street Shipyard in Belfast, or any of those places would let me walk through the front door without a credit check. My family has been summering there since the 1930's, and I'm very friendly with most of the lobster boat owners who I'm sure will point me in the right direction once I get the boat up there. Throw in Hamilton Marine and I think I'm pretty well covered.

So DennisG01, sounds like you can see the Olson House from your back porch!
Click to expand...
A'yuh :)
 
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