1999 seacraft repower

[mjl]

I'm considering repowering my 1999 lefty sea craft. It has the original 1999 150 Johnson with 2000 trouble-free hours! Between relocating the boat to an area where we'll be making long runs with new baby & how noisy / smokey it is, I think it's about time.

I was thinking about the df140a or the new mercury 150 4s. My biggest concern is weight and keeping the water draining out properly. Speed & efficiency is important also as I have a 45 gallon tank & long runs in flat water.

please let me know what you guys think.

thanks,
mike

[McGillicuddy]

Sounds like you're going 4 stroke, but I think you'd be remiss not to consider the etec. Is the boat the 20 or 21? If its the 20, a 115 would be very similar in weight to your old motor and probably be really close on performance. If the 21, I think a 150 would suit your stated needs, and you can opt for a 175 or 200 in same weight class. They are super efficient and quiet.

[mjl]

Thanks, I believe my motor now is around 360lbs. I'm pretty sure I'd like to go 4 stroke as long as I'm mot pushing the weight limits. Just hoping to verify that adding 60 to 100 lbs of motor will have a negative effect.
The 115 etec would probably be a great match for weight & efficiency, but i would think take a lot off the cruise speed.

edit: it's a 20

[Fr. Frank]

Actual cruising speed for most boaters in exposed waters (not the Gulf of Mexico or the ocean) averages about 25-30 mph. I would compare the fuel economy of various motor tests at cruising rpm's and the speeds the provide.

I think Gillie's advice on the 115 Etec is very wise. You should be able to average over 5 miles per gallon at cruise. I think that will be more than 20% better than the 150, and 10% better than the 140 Zuke. You might sacrifice up to an equal percentage in top speed, however.

Denny reports the 115 Etec makes at least 8% over rated horsepower at the propshaft.
I have an acquaintance with an '06 21' Kenner VX who just bought a 2014 115 Etec to replace the original 135 hp Evinrude V6. He claims he actually has exactly the same top speed (41 mph), but went from 2.2 mpg at 28-30 mph, to "about" 5 mpg at the same speed, more than doubling his fuel economy.

He's a diehard Evinrude fan, and actually picked the 115 Etec over the 150 because it was only 405 lbs, while the 150 Etec was 435 lbs and $3K more expensive.

[craven]

i like this site a lot. have learned an awful lot reading all your posts. i'm researching (and agonizing) about the same repower/new power question. my seafari has a 25" transom and the deck has been raised 1 1/2". it's down to suzuki 140a. the 25" weighs 408# or an etec 115 or 130(for $2500 less-either one same price-if i rig it myself). the etec 25" weighs 390#.
add the oil in to both, you're damn close to even. i know many folks advocate big power on the 20. not me. i hook fish commercial and the secret is keep your nut SMALL. fuel economy is paramount. throughout the season, an extra few gallons per day adds up to a lot.the only things i don't like about the etec is that it sounds like it gets a little less mpg than the 140A, and when i'm backtrolling the exhaust from the etec 200 i have on another boat i'm selling will leave me with a quite a headache. yes i use xd 100 oil and the motor is programmed for it. thoughts would be appreciated. this motor will see 500 hrs a year easily so i'd like to get it right. also how high would you mount the motor on the transom? the 2 batteries are in the cuddy. i think these are the same issues the guy who started the thread is dealing with so i thought i'd throw my question in with his. i've never replied to a post or started a new one in my life, so go easy on me. thanks guys

[seakat]

I sold my 2000 SeaCraft20 w etec150. I loved that combo. I now have a SeaCraft23 w F250. If I were to repower, it would be an etec. The etec was very responsive, much easier maintenance, winterized itself, will run on regular gas. I never noticed an oil smell.
Good luck w your repowers. I never felt overpowered and it is nice to have some reserve power to handle a load. Underpowered boats are sensitive to wt.
I had a jackplate so I didn't pay attention to mounting ht, but the boat is local and I could try to get a measurement if it was critical.

[Bushwacker]

Craven, if you do a lot of trolling, a 115 E-TEC may actually burn less gas than the 140 Zuke, as all the test data I've seen shows that they burn less than the 4-strokes when they're operating in the stratafied charge region, below about 1500 rpm. My 150 burns 0.5 gal/hr at 5 mph and about 900 rpm and I'm sure a 115 would use even less with 1/3 less displacement. I've made several long trips with mine of 200-700 miles, loaded very heavy and cruising at 27-28 mph and consistently average about 4.3 mpg with minimal idle time. I use the I-Command gauge which accurately tracks fuel consumption, and on shorter trips closer to home with lighter loads, numerous idle zones and trolling, I'll often average 5 mpg on a typical day trip. I'm sure the Zuke is a 5 mpg rig and a fine motor that I considered back in 2006 when I was looking to repower. Like you, I think the 20' hull rides and handles better with a lighter motor, since I ran mine for 31 years with a 300 lb 115. My first choice was the 115 E-TEC but they were not yet in production at the time, so I went with the 150. I've ended up running with much heavier loads than I expected, so I've enjoyed the extra torque of the 150, but the 115 is a very strong motor and more than adequate for the Seafari if your happy with a 25-30 mph cruise speed.

[Terry England]

Originally Posted by craven

i like this site a lot i've never replied to a post or started a new one in my life, so go easy on me. thanks guys

First you must be verbally Keel Hauled -
Have you completely discounted quad Eska's on a Bob's Jack Plate or the Porsche 911 Go Devil....? (No water pumps to mess with....!)

Just Kidd'in
See what Padre Frank, Gillie or the other great CCS crew suggest. It's like a re-power Think Tank here.

[craven]

thanks guys for the replies. from reading around the posts here i'm thinking mount the cav plate 2" above the lowest point on the bottom. with room to drop it down a hole if need be. does that sound right? anyone care to fine tune this concept?

[FishStretcher]

I hate smoky motors. Don't discount a correctly propped Yamaha F90. 367 lb. awesome corrosion resistance. I have an ex Florida rental motah. A F100 from 2000. The F90 turns 500 fewer RPM. At LEAST 800 hours on it. No corrosion. I put a 20 gallon tank in the boat. Not a 100 gallon tank. I think it gets better than 5 MPG at cruise. With the right prop it pops on plane. With the wrong one, not so much. Light enough I keep a 4S kicker mounted on the transom.