TOPIC: Repowering Discussion

I'm contemplating repowering my 1963 Aristocraft Funliner. I was looking for some input on anyone that has repowered to modern power.

My boat is 16' long, 86" wide, 20: transhom height, weighs about 500lbs. Current motor is 1966 Golden Meteor 100HP that weighs about 275 lbs.

Motors that interest me are:

90 HP Etec 320lbs
90 HP Mercury 359lbs
90/100HP Honda 359lbs

My boat currently goes about 38 MPH and with some effort can get a person up on a single ski. I would like to be able to do that with 3 people in the boat with the new engine.

Thoughts, opinions??

You need to be careful of the weight on transom Dave. I think the 320lbs would be pushing it but others can jump in here.

Bob

Damartinca:

We did a "repower" on both our 1960 Glasspar G-3 Skiboat and on our 1960 Glasspar Seafair Sedan.

On the 1960 Glasspar G-3 Skiboat, we went from a 1964 Mercury 65 H.P. to a 2009 Mercury 50 H.P. The newer engine weighed less than the old Merc 65, weighing in at a very light 204 lbs.

However, our 1960 Glasspar Seafair Sedan had a 1980's Johnson 60 H.P. Two-Stroke which I was told weighed about 240 pounds. I went with a bigger 2010 Mercury 90 H.P. Carbureted Two-Stroke which weighs (according to my Mercury Manual) 303 pounds. With that being said, our Seafair Sedan weighs about 750 pounds and is 18 feet long, somewhat bigger than your boat.

I hope this helps you some Sir.

Thanks it does. My boat is very wide and I have been studying where it sits and getting some other anecdotal evidence.

I actually haven't heard of anyone having a problem after repowering. I have heard some people have had to move some stuff around within the cabin, but nothing earth shattering.

Obviously, the hull has to be able to handle the new power. So, that is where I am starting....

Thanks,
David

Horsepower wise you'll probably be a draw as modern outboards are rated at the propeller.. The old 100 HP was rated at the crankshaft and probably only put 85-90 HP to the propeller after losses in the gearcase.. Your biggest issue will be how the boat handles the added weight of the newer motors, try adding sand bags or bags of lead shot on the deck under the motor well on centerline.. Add enough weight to approximate the additional weight of the heaviest motor you're considering, go launch the boat and see how she sits on her lines and performs with the additional weight..

Thanks. Great suggestion. I have been studying boat photos of my boat with various people in it o9n vacations and trips to look at how the weight affected it. I think my transom is wide enough that it should have minimal effect. I probably will have to get smart tabs if it ends up being too stern heavy.

Sincerely,
David

Glad to help..

If your original motor doesn't have power trim, I wouldn't worry too much about having to fit a set of trim tabs.. Most all the modern motors in the 90 HP range come with power trim as standard equipment.. Having power trim on the motor will help overcome any increase in weight on the transom, just trim the motor all the way "in" before accelerating from a dead stop and you'll have no problem coming out of the "hole".. Once the boat begins to get on plane, slowly trim the motor back "out" until the boat begins to "porpoise" then trim it back "in" slightly, that will be your optimum trim setting.. You'll also know when the trim is set right as the steering effort will be somewhat reduced..

Just be careful with the weight at idle or at rest. I over-repowered my Tomahawk from a 40 to 135hp. Went like the dickens and easy to handle but with two full gas tanks in the stern you better not stand in back cuz water does come through the transom upper drain holes.

Depending on which motor you choose,(ETEC ), you add 45 to 84 pounds, about the weight of a small child. Propeller selection is much better, and the right prop should achieve your skiing goal. Fuel savings and power trim are nice bonuses.

Great info. Yes, it look slike I'm leaning toward the Mercury at this point. Found an incredible deal on a 2016. just waiting to hear back on structurally what might need to be done on the transom.

In studying pictures, I had someone 200lbs standing at the rear of my boat and it looks like the resting position barely went down an 1". I have a nice huge self-bailing splashwell, so I think that will be help.

Good to know about the trim tabs. I was under the impression they would help to stabilize my boat from leaning left or right, especially since I'm frequently by myself in the boat.

So excited. I hope this all works out. California finally has water!


Thank you everyone for taking the time. Incidentally, here is the creative way we took off the old motor.

If you're looking to correct uneven side to side loading, spring for a set of Lenco or Bennett trim tabs.. The electric or hydraulic models can be individually adjusted from a dash mounted control unlike the Nauticus "Smart" tabs that have to be manually adjusted at the tab by trial & error..

I'll check them out. Have you seen the Bennett Self Adjusting. I'm sure they work along the same lines as the smart tabs. They look pretty cool and easy to install.

If possible, you might want to consider putting the gas tank(s) under the bow. When I had mine, it only had a 40 hp, but putting the 2) 6 gallon tanks I carried up there made a world of difference in handling and stability, especially when I had 4 adults in the boat...of course it was a bit of a dog with all that weight then, but it was unbelieveable with just 2 of us!