Re-power questions - Maxum Boat Owners Club

Delmarva · 05-25-2012, 02:17 PM

If I choose to re-power my 1989 maxum 2002, do i go strictly by horsepower, weight or combination of both. It has a Force 125 on it now.

John

seapuppy · 05-25-2012, 06:16 PM

well..some of the newer outboards are lighter and provide more hp...so..if it were me..I'd look at weight....the newer outboards power to weight ratio is much better plus the fact that they are 4 strokes..meaning better gas mileage and smoother running..more reliable.....get a little lighter engine with the same hp rating and the performance of the boat would overall be drastically better........

SP

Delmarva · 05-25-2012, 07:45 PM

Thanks SP, the Force runs now but I would want to replace it over the winter.

John

tglee · 05-25-2012, 08:14 PM

Quote:

..some of the newer outboards are lighter and provide more hp...so..if it were me..I'd look at weight....the newer outboards power to weight ratio is much better plus the fact that they are 4 strokes..

Well that’s not necessarily true. My 1994 115hp 2-stroke Mercury weighs 348lbs. While a new 4-stroke weighs 400lbs.

seapuppy · 05-25-2012, 08:41 PM

yeah..but what's the hp-lbs ratio???.....the newer engines are producing more hp...

SP

shrew · 05-25-2012, 09:23 PM

I would say that, in general, the ratings for Outboard(OB) weight, OB HP, and total weight are not and either or, but both. The HP rating and weight rating shoudl BOTH not be exceeded. Yes a 4 stroke will weigh much more than a 2 stroke. Let's not even add that depending on the year the HP was measured on the head vs the prop.

If you're looking for your best power to weight ratio, then you might want to look at a Evinrude e-tec. They are 2 stroke, very quiet, light, and environmentally friendly. They can get you up to the HP limit without compromising the weight.

Just my .02

tglee · 05-25-2012, 10:09 PM

Quote:

....the newer engines are producing more hp...

Umm... I think my 94 115hp is the same as a 2012 115hp

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mcoffey · 05-25-2012, 10:17 PM

If it were me, I would get the biggest HP motor that was legal for that boat. It should be listed on the capacity label what the MAX HP is. If it states 150, upgrade. I have never heard anyone say, "I wish I had gotten a smaller engine". It is always the other way were they want bigger.
So if it is too much power, let off the throttle a bit. Not much you can do when there is not enough HP.

Delmarva · 05-25-2012, 10:37 PM

This is all new to me so if my questions sound simple that's why. I don't know the weight of the Force, but if it weighs 300 pounds and a larger one is 400 pounds, wouldn't the extra 100 pounds come off the total load capacity? Does the HP limit come from fact that higher HP motors weigh more, or is it a question of transom strength?

mcoffey · 05-26-2012, 01:19 AM

This might help a bit. This is the US Coast Guard Boatbuilders Handbook and covers capacity and HP calculations for outboard boats (section 2). Basically it is weight of motor, battery and fuel tanks that determine what it can hold.
So if you are rated at 125HP MAX, I would stick with that or as close as possible (like 120HP or 115HP if 125 is not available).

http://www.uscgboating.org/assets/pd...AFELOADING.pdf

Delmarva · 05-26-2012, 01:47 AM

Thanks mcoffey, I'll have this season to figure things out. Who knows, maybe the Force will last longer than most people seem to think.

John

mcoffey · 05-26-2012, 03:12 AM

Let's hope! Have you looked at prices of new ones yet? WOW
Seems most make 115HP and are around $8000 to $9000 (Yamaha, Honda, Tohatsu).
Mercury does have a 125HP for around $9000.
These are all new of course and I am sure you can find a nice used one for less.

Good luck with whichever route you take here