Too much weight? Any recomendations
 

I am thinking about upgrading my motor to a 2002 Yamaha 225 VMAX that weights about 539lb. I am concern about the weight on the transom, would it sit too low?

What do you guys recomend, and what do you think may be underpower?

Many thanks!

what size boat do you have? it is definetly heavy for a 20.

i have a 1985 MA 20ft.

it definetly sounds heavy for that. are you running 20 inch transom or 25 inch? my 200 mercury weighs in at 395lbs and i cant imagen using anything heavier. and mine was 25 inch transom and i closed it in and installed a bracket because of the low open transom.

I am running a 25inch transom.

So, should i downgrade to something less than 200 or should i stay at 200hp? I am worried about been underpower and having an engine that may weight too much on the boat, which will affect the ride.

the biggest thing to look for is weight to HP ratio. for me ive always seen mercury to be the lightest motors, early ones. all new engines are gonna be heavier especially 4 strokes. you realy dont want to exeed 400lbs on the transom if you can avoid it. thier are some realy good threads in this section just look around and get an idea of what you want. and alot of people here run much smaller engines and are very happy with them, just depends on what you want. racer, fishing, all around good performance? 200 on these boats is alot. ive seen some 225 and they just fly scarey in my opinion, realy just to much motor! good luck on your choice.

Even a 200 is more than enough for a 20' SeaCraft, especially if you run intend to run offshore very much. It's a relatively light hull and tends to go airborne at speeds over 20 kts in seas over 3'. Adding more power that you can't use only adds excess weight to the transom and screws up the CG, raising min planing speed up to around 20 kts and hurting the ride.

I think the hull was originally rated for 170 hp and is much more efficient than most modern hulls, so it will plane at 10-12 mph and performs well with lightweight motors as small as 85-90 hp. I ran mine for over 30 years with a 300 lb V-4 that was about 100 hp at the prop and it was better balanced then than it is now with a 420 lb motor on a bracket. I had to go to a stern lifting 4B prop and a Doelfin on the new motor to get the min planing speed down to 12 mph where it was with the old motor! I think the optimum motor for the 20' hull for offshore use is about 130-150 hp and weighs no more than about 375 lbs!

Actually, the original maximum HP rating on the outboard 20' was only 140 hp, until 1974 when it was raised to 175 hp.

The 20' hull was designed for single outboards of less than 300 lbs or twin outboards of less than 450 lbs total transom weight.

In 1969-71, they did make some of the 20' hulls to carry twins, but the1971 70 hp Evinrude/Johnson only weighed 202 lbs in the 20' shaft, and the '71 Merc 650 65hp was 217 lbs. These boats also had a larger fuel tank beneath the console, of (I think) 40 gallons capacity instead of the 27 gallon tank.

The stanard motor at the largest dealer on the west coast was the 150 Merc inline - of course that was it. Then Merc did the V6 175 and the boat rated for that - 150-175 is fine, 200 is OK but somewhat overkill - and mine has a 200 and it will pin your ears back.

and in no uncertain terms will it handle 593lbs - 400 is it

Don't worry much about underpower. Light on the stern is usually better. I ran a 20 seafari(same hull as yours) for years with a old merc 150, often vastly overloaded with divers, 9-10 tanks, multiple iceboxes full of ice/fish etc. It had more power than I needed and no problems at all in maintaining a good cruising speed (25 knots or so). It would hit 40 light. Far more important is a combination of engine, prop, and hull that is able to stay on plane down below 15 knots.12 or 13 can be heaven when it gets nasty.

Right now i have a 200hp Yami, 1989. I am trying to find the weight of that engine, which i cant find anywhere! i have not noticed it sitting low on the water, but i feel the stern sink low some times when running it before planing.
I concluded that the 225hp is out of the question, i'll be in the market for a 200hp that weights less than 400lb, or 400 exactly.

You guys are great help!!!!

225 Vmax is over kill and really too much weight. Better suited to a 23'. Even half of that power is sufficient to satisfy a 20 in most cases. Case in point, I think it was bitsamonkey that recently re-powered his 18 with a Suzuki 90 and showed 6.9mpg at 27mph cruise, topping out at 37mph. I have a healthy 115 tower of power on my Seafari 20 and have yet to actually "need" more power.

Your '89 is listed at 390 lbs. You wont find a modern 200 anywhere near that light. Maybe 490. 1990's Merc 200s were only a bit over 400 lbs.

Some of the 175s like the etec may be close at maybe 435 lb but still out perform your older Yammie.

Good luck.

Is there anywhere where I can find the year, horse power, and weight of motors? Is there like a chart? I've looked everywhere onlinr and I dont find anything.

oops! here it is... NADA helps! =) year, make, model, HP, and weight!!!!

http://www.nadaguides.com/Boats/1997...utboard-Motors

Well i am the second owner of a 150hp Mercury 1997, thats in very conditions, very clean and with great compression!