Power for 20'

[Calibogue]

What is the general consensus regarding power for my 20?
I'm looking at a Yam 150 4 stroke........What kind of performance can I expect? Will the boat handle a 200?
Weight limit with a bracket and the fuel moved forward?
I would love some feedback from anyone with thoughts!

[whitly]

i just went through this for my 20' Seafari. when all was said and done, i went optimax 175. weight, economy, performance, price, proven history, boat rating were considered and when i added and subtracted, divided and multiplied, it was clear. the only hard part what deciding on merc vs e-tec. that came down to a color choice. turns out, the trim and bottom paint are black, so i had to.

just my $0.02

good luck, whitly

[Bushwacker]

I had similar questions when I repowered 2 years ago to replace the old 115 Evinrude I bought new in 1975. (Which was still running great by the way - sold it for $400!) One basic fact to remember is that when Carl Moesly modified the 19' bowrider to create the 20' hull in the mid-60's, the biggest outboards were the I-6 Mercs and V-4 Johnrudes, which weighed about 275-300 lbs. When you go heavier than that, the boat gets stern heavy and I believe it progressively screws up the ride. The Seafari's have more weight forward and can probably tolerate a heavier motor a little better than the CC's which look a little stern heavy to me. With all our gear in the cabin, mine rode extremely well with the old V-4 on all my Bahama trips, and I could trim everything down and plane at 12-14 mph when it got really rough. The Hermco bracket, which has biggest of all flotation tanks, largely offsets the weight of the new motor at rest, so the new static waterline is within about an inch of the original and boat is still (just barely) self bailing. When you're on plane however, that flotation tank doesn't help, and the additional weight set further back tends to raise the bow. I had to go to a 4-blade stern lifting prop and a Doelfin to get back the original low speed planing capability. The bracket will improve top speed by 2-3 mph, but it will hurt low speed planing capability if you put too heavy a motor on it. Most of the 150 4-strokes are close to 500 lbs if you include weight of the cowling and fluids and that's too heavy IMHO. A V-6 4-stroke is even worse, for the same reason. Now if you boat mostly in flat inland water, want to cruise at 40 and don't care about ride, then go for the big motor. However if you run offshore and care about overall balance and boat capability, less is MORE! You'll also spend less on insurance if you don't exceed the hull's 170 hp rating!

The E-Tec, Optimax and 140 Zuke are lighter, will get nearly equal or better fuel mileage, and provide plenty of power for the 20' hull. If you want good fuel economy, I'd even consider the V-4 115 E-Tec, which I suspect is about a 125 (BRP is sandbagging on the hp ratings) and is about 50 lbs lighter than the V-6. I picked the E-Tec because it's MUCH quieter than the Merc (even quieter than the 4-strokes @ 30 mph), is very close in fuel consumption, has a lot more mid-range torque than the Zuke (BRP brochure shows E-Tec's really a 165 hp motor), and is by far the cheapest to maintain. There were some negative comments here recently about E-Tec durability and cost of the XD100 full synthetic oil being $50/gal. The cost may be true in some areas, but I bought a gallon from dealer last month for $32. (He buys in bulk, just bring your own jug!) I have had zero durability or maintenance issues in two years, have only used 2 gal. of oil in 133 hrs (less than if I had a 4-stroke!), and am averaging about 5 mpg. My dealer also sells Yamahas and Hondas, and says he's had fewer problems with the E-Tec's than the others, so I suspect the durability talk is more competition-sponsored rumor than fact. The I-Command Classic analog style gages were a disaster however (Digital I-Command gages are fine and provide more info), but BRP did stand behind them, and gave me two 3" digital gages worth over $500 to replace the tach and spedo that died, even though they were out of warranty!

If you want to PM me with your e-mail address I'll be glad to send you a multi-page spreadsheet I put together comparing all the 150 hp outboards.

[eggsuckindog]

Bushwackers boat is about as well balanced as I have ever seen. Honest I would stay away from 4 strokes, as he stated the etec's have all the same advantages without any disadvantages. Check out the picks of his boat in the gatherings section and you will see what I mean, not sure what the weight difference is ?

[Calibogue]

As of yesterday I decided to hold out and search for a 150-175 Optimax. They weigh the same so I will lean towards the 175. I made this decision b/c #1 I dont want to rush into anything, #2 it will aloow me ample time to rig her, and #3 I have a Merc rep I love working with.
I would however love to see that spreadsheet...
scott@forestmanagers.net
Thanks!

[zach]

As of yesterday I decided to hold out and search for a 150-175 Optimax. They weigh the same so I will lean towards the 175.

Might want to consider the 175 Opti Pro XS. That's what I just bought for my 20. Haven't hung it yet, but once I do I'll make sure to post performance numbers.

[Bushwacker]

. . not sure what the weight difference is ?

Dixon - thanks for the kind words! Assuming you're talkin hull dry weights, here's what a '76 brochure lists for the outboard models:

20 Sceptre - 1650#
20 Seafari - 1800#
20 SF & MA - 1600#

[Ikan Besar]

Honest I would stay away from 4 strokes,

Agreed, I just HATED mine (140 Suzuki). It never hiccuped once in four years, fired up annually after six months of storage as if it has been running two minutes ago, was nearly silent at idle, burned a gallon of gas every five miles at 30mph, etc. Yep, it outright SUCKED! [img]/forum/images/graemlins/tongue.gif[/img]

The Amish aren't much into internal combustion engines either but some of us really have grown to tolerate all the problems associated with them...

[billythekid]

Ikan what prop were you running on your 140 suzuki?

[Ikan Besar]

Ikan what prop were you running on your 140 suzuki?

14x20 stainless, pushes the boat at 41mph at 6K rpm. I sold the boat recently to forum member Old Bull but the boat can be seen in the gallery section under the heading "Mark's 1971 20'CC".

Having now had a 4-stroke, I'd never voluntarily buy a 2-stroke again.