90 hp four stroke on a Seaway 23?

wiggy

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I was wondering if anyone had used a 90hp on a Seaway 23 or something like it? I was originally looking for a 115 four stroke but I keep seeing deals on 90 hp four strokes. I'm not looking for a speedy boat just a solid cruiser. Seems like the fuel economy even at a slightly higher rpm might be a little better and the weight is certainly less as most of the 115 hp engines I see are based on the larger 150 engines. Anyone running around with a 90 on a 22 or 23 foot skeg/cabin boat? Do you regret it or is it enough?
 

Surfishingboy

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a friend of mine had a 23 sea way cc with a 90 suzuki and i think it cruise in the lows 20s.
 

rockfish

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I believe the 115hp and the 90 hp Suzuki 4S are both made from the same block. The 115 is 416 Lbs and the 90 hp is 341 Lbs so 75 pound dif. I would go with the 115 fisherman carry a ton of gear
 

MouseTrap

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The Suzuki 115 and the 90 were the same block (and were the same weight). A few years ago, they increased the output of the 70 to 90 by adding variable valve timing, and remapping of the ECU. Therefore the 60-70-90 now are the same weight.
 

SHORT STEP

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4 stroke

before i put a 115 four stroke i would put 416 lbs in the stern and see how it sits
 

wiggy

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a friend of mine had a 23 sea way cc with a 90 suzuki and i think it cruise in the lows 20s.

A 20 knot cruise would be fine for me. We use a Yamaha 115 four stroke on one of our school's boats and its huge! I looked at a 2005 Honda 90 yesterday and it seemed smaller (usually Hondas seem huge to me). Don't know what the difference in weight is, but it might be worth a try if I can get low 20s. They're all so #$A%* heavy!
 

Tunascapes

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If it helps, I have a 90 etec on a 19 seaway and can top out at 33kts and cruise comfortably at 25kts. I have a 225 etec on a 26 seaway and it tops out at 31kts and cruises at 21kts. For a 23 my choice would be a 115 but I would think a 90 would give you low 20s. You are going to be working it pretty hard to get that done though.
 

cjmahm

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I repowered my Seaway 19 with a new Suzuki 90 Hp last winter and I love it. When I am loaded up with people/gear, it is definately a little slow out of the hole (compared to how i have seen ETECs pull), but it is a fantastic motor. The gas mileage has been unreal compared to the original Johnny that was on it, and the lack of noise/fumagation, has been wonderful.

I think with the added length and weight of the 23, you would be good to go up to the next size though if you desired. The placard on mine says the 19 was rated for 70 to 115 hp, but that was back in 1987 rating the two strokes and their weights. That being the case, I am sure you could pull off a 115 if you wanted, but who needs to be in a hurry? It's a DE afterall.;)
 

joman

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If it helps, I have a 90 etec on a 19 seaway and can top out at 33kts and cruise comfortably at 25kts. I have a 225 etec on a 26 seaway and it tops out at 31kts and cruises at 21kts. For a 23 my choice would be a 115 but I would think a 90 would give you low 20s. You are going to be working it pretty hard to get that done though.

You are suggesting a 115 etec and could you guess how many miles/gal. that you might get?
 

Tunascapes

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You are suggesting a 115 etec and could you guess how many miles/gal. that you might get?

I'm not saying an etec. Pic your choice of a 115. I think you will save some weight with an etec and that will help your scuppers but any will work. I honestly can't tell you mileage on the 90. I don't keep track of it the way I use that boat. On the 26, which is a completely different hull design we are doing 2.5-3 miles per gallon depending on how we are loaded. Again the 23 is much closer in hull design to the 19 than the 26.
 

bglhooked

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I had a 19 seaway with a 60 2 stroke and it topped out at about 24kts empty. Once loaded up with 4 guys it was 19kts wide open. If I were you i would put the biggest motor you can on that thing considering its weight/horsepower of course. Remember, you don't always have to use the power but when you got it, it sure is nice.
 

tomy

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have a 19' seaway with 90 e tech. great combo,,would not hesitate to put on little larger boat.
 

BOSBoatMan

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If you go on Evinrude's website they have all sorts of speed tests and ratings for all their motors so you can see the hard numbers behind the engines. Of course, they're mostly Florida boats and such, but you can get a reasonable idea of fuel burns for each....
 

wiggy

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If you go on Evinrude's website they have all sorts of speed tests and ratings for all their motors so you can see the hard numbers behind the engines. Of course, they're mostly Florida boats and such, but you can get a reasonable idea of fuel burns for each....


These reports are interesting, there's a lot of pontoon and aluminum boats on there, wish they had more glass boats. I didn't know the etec could get that sort of fuel economy. I'll end up with a 115, I'd rather have the power, its easy to throttle back if I don't need it.
 

BOSBoatMan

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These reports are interesting, there's a lot of pontoon and aluminum boats on there, wish they had more glass boats. I didn't know the etec could get that sort of fuel economy. I'll end up with a 115, I'd rather have the power, its easy to throttle back if I don't need it.

Same here I was going to put a 75 ETEC on my 17 Leblanc but since I am already going to 320 pounds on the transom why not just pick up another 15 horsepower...lol
 

MASTERENEGADE

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I agree. I currently have a 18' privateer cc with a 2000 90hp johnson 2 stroke.
When i have to repower(hopefully not soon) i plan on going with a 115hp e-tec instead of another 90hp. I think the 4cylinder 115 would give me more torque then the 3 cylinder 90hp. I maybe wrong, but this is where my feelings are at

the boat currently tops out at 32+knts i cruise at 20-24knts depending on conditions.
 

novivin

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90 4 stroke yamaha on full wheelhouse 22 foot novi

Hi,

i have a soft-chine 22 foot novi.

The hull is a rare one, only a few made. It is a small cape-islander, not the tubby kind, like leblancs.

I posted pics here if you search for Gaski that was the builder. They hav since discontinued producing it.

I think the boat handles really well. I can't imagine why they stopped making them.

I do 14-16 knots at 3900-4100 rpm fully loaded, gas gear and family (4).

The boat does 26 knots open at 4800-5200 rpm with just me, gear and rod and reel stuff aboard.

I carry tools and spare stuff at all times, plus the required equipment, and two batts.

If you want 20 for a cruise speed then I think you need the 115, at least.

23 seaway was a soft chine, same basic hull shape below the water as me. I have seen many seaways.
 

seewhey

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I do have a 23 seaway, used to have a 200 on it.. real fast. Last spring I was in the market for new less thirsty power and narrowed my plan down to the f90 or f115. I work with my boat and its loaded up pretty good alot of the time, combined with a larger than average wheelhouse, the 115 was the way to go. I think I would have been disappointed in the performance of the 90 on there.

as far as numbers go, on an average day, fuel consumption is 2-3 gph
cruise speed is like 15 knots at 38 or 39 with the flat wheel and all my junk onboard. Add a couple people and it goes down, but its not bad. I have a 15.5 and a 17 prop which is pretty nice for maximizing efficiency depending on what I am doing.
I love the f115. It never misses a beat, so good on fuel, so quiet.
 
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wiggy

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I do have a 23 seaway, used to have a 200 on it.. real fast. Last spring I was in the market for new less thirsty power and narrowed my plan down to the f90 or f115. I work with my boat and its loaded up pretty good alot of the time, combined with a larger than average wheelhouse, the 115 was the way to go. I think I would have been disappointed in the performance of the 90 on there.

as far as numbers go, on an average day, fuel consumption is 2-3 gph
cruise speed is like 15 knots at 38 or 39 with the flat wheel and all my junk onboard. Add a couple people and it goes down, but its not bad. I have a 15.5 and a 17 prop which is pretty nice for maximizing efficiency depending on what I am doing.
I love the f115. It never misses a beat, so good on fuel, so quiet.

Great info! 15 knots at 2-3 gph would be fine. Any pics of your 23 on the website? I'd love to see a couple of pics of her. Thanks -Lane
 

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