motor weights, too much?

2182 · #1 05-03-2009, 09:25 AM

been researching motors for repower in the near future. looking at something between 150 and 200 hp. boat is 18 sf. looking at yami and suzuki. all motors are weighing in between 465 andf 475 lbs. i have an older (92) merc offshore now which i believe weighs 410 lbs. i like how the boat runs now. not being too concerned w/ planing at low speeds, is that extra weight going to be a factor? rarely run w/ more than 3 people (usually 2 counting me) and boat is not overloaded w/ gear (it is an 18 ftr after all). i did build a 35 gal livewell on it and it has a 48 gal gas tank, though its rarely full. any thoughts are appreciated. im getting $ back from uncle sam for the first time ever and figure ill sink it into our floundering economy.

PressureDrop · #2 05-03-2009, 10:59 AM

i know you said your looking between 150 and 200, but i would seriously consider the suzuki 140, its lighter by about 50 lbs. and it will take a while to burn through 48 gallons of gas. unless you have a serious need for speed its worth considering. youd still see 45mph top end if you have a clean bottom...

eggsuckindog · #3 05-03-2009, 04:55 PM

I had one with an inline 115 Merc, ran just fine and I was a young go fast buck then. So anything 115 and above will work fine, they even acme out with some new 4 cyl Etec's even an HO model along with that 140 Zuke - I think 465/475 is too much for it. My 200 Merc on a 20 and at 416 thats about it.

Bushwacker · #4 05-04-2009, 01:15 PM

Sound like you're looking at 4 strokes. Don't know what your objective is but if you want speed, stay with a 2-stroke! Be advised that weights on those motors are really closer to 500 lbs because the quoted weights are DRY weights! When you add 6-7 qts of lube and gear oil that's another 35-40 lbs! I also understand they don't include weight of the cowling, since that's not on the motor when they hang 'em from a scale!

I agree with Egg that the 150 4 strokes you mentioned are way too heavy. You have to remember that Moesly designed the 19 Bowrider and 20' hulls for 300 lb motors! As you get over that, you're progressively screwing up the balance of the boat, and I'd think the smaller 18 is even more critical.

The heaviest 4 stroke I'd consider is the 140 Zuke and I think it's a little heavy for an 18. Suggest you send a PM to Snookerd, as he had one with a V-4 2 stroke and his dad has one with a 140 Zuke. I believe he feels it'd ride better with a lighter motor.

Fr. Frank · #5 05-04-2009, 04:25 PM

The perfect motor for the 18 is the inline 6 Mercury 140/150 hp. (Same motor, the 140 is prop-rated, the 150 is powerhead rated.)

The Merc XS1500 150hp actually produced an amazing 215 hp at 9000 rpms, but the listed max rpm was 6000.

I ran my 1st Seafari weighing 1800 lbs with the inline-6 150 hp Merc, and top speed was 44 mph. You can still find them on Ebay, and there are several places around the country which specialize in remanufacturing the "Tower of Power"

Snookerd · #6 05-04-2009, 05:41 PM

Quote:

The heaviest 4 stroke I'd consider is the 140 Zuke and I think it's a little heavy for an 18. Suggest you send a PM to Snookerd, as he had one with a V-4 2 stroke and his dad has one with a 140 Zuke. I believe he feels it'd ride better with a lighter motor.

Bushwacker is correct. Only motors I would put on an 18SF to have the intended weight for the boat is below 380lbs. My family has the 140 Zuke on their 18SF and it does fine, but it isn't close to being self-bailing.

2182 · #7 05-04-2009, 06:43 PM

damn you guys are good. thanks a lot. i love all the info on this site. on the bright side we all run boats w/ 20 year old hulls so the big $ item is the motor. 140 zuke sounds good, you really think i can get 45 out of it? i do like to go fast but 45 is doable (clean bottom, no bottom paint). as far as the 2 stroke v. 4 stroke, ive always (last 3 anyway) ran 2 stroke mercs and had good luck, but im thinking of going new and i dont like the opti, its gotten too much bad press. ive heard they worked out the kinks but id rather not be the lab rat for it. also, really nobody is running yammis on their seacrafts? all the bigger boats i fish run the hpdi and love it. just a weight issue?

asdfhood · #8 05-04-2009, 09:16 PM

I bought Snookerd's 1987 ( I think) 18. It had a Yamaha 130 4 cyl 2 strk. I replaced it with the same. It took some searching but i found one with low hrs priced right. I think some will agree that this is the ideal power for this hull. I am in Columbia and fish Charleston and Lake Moultrie. The Mercury Tower of Power sounds good but every one I found was very long of tooth.

eggsuckindog · #9 05-04-2009, 11:15 PM

Look at the new Etec 115 HO, will be right at 125 HP and has the Lightning gear case which is smaller than the 130, it should have a bit more zip from fuel mapping and stuff since its a kinda go fast motor. Still think its about 369#, but a 100+ pounds is a ton on the transom, that should give 45 easy.

asdfhood · #10 05-04-2009, 11:21 PM

Sorry, I ended the prev post too soon. I was going to bring up the 115 E=Tech, and also the 130, or 135 Etek. I seriously considered the 115 but boat was already regged for Yamaha and I found a good motor at considerably less $$. But there is always tomorrow and Evinrude seems to loom large on the horizion (sp?)