Malahina with Mercury 75 HP 4 stroke

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jlwright
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Malahina with Mercury 75 HP 4 stroke

Post by jlwright » Mon Jan 14, 2013 7:14 pm

I looked up the weight on a new Merc 75 HP 4 stroke and it weighs 399 lbs. the 2 stroke version weighs 375 lbs. it seems pretty heavy but I didn't see any specs for the weight of the engine on the Malahina info. Does anyone see a problem with using the 4 stroke Merc? Also, are there any other good options for the same size engine in a four stroke but in a different brand. I'm not totally stuck on Mercury I just don't have any experience with other brands.

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Iggy
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Re: Malahina with Mercury 75 HP 4 stroke

Post by Iggy » Mon Jan 14, 2013 9:08 pm

Hi!

My 2-Stroke 90 HP 1989 Mariner (UK version of Mercury) say's its 265lbs on the spec sheet, but I can tell you it feels a hell of a lot heavier when I had 4 guys to lift it a couple feet onto my transom and felt more like 300lbs to me.

My Malahini has that motor on the transom and a 18 gallon tank and battery are stored under the motor splashwell, and the boat sits pretty low at stern, more than I would like. You can see a video of my boat launch here: http://www.youtube.com/watch?v=vGZKuYxOKTo

Now, a smaller tank, or moving either the battery or the tank under the front deck might help to level it out, still thinking about that.

However at speed (on a plane) everything seems to work just fine.

I wouldn't want anything much heavier that what I have. 75 HP is fine for power, well within the limits of the hull restrictions, but anything over 300 lbs of weight would give me pause.

I am sure you can get her on plane with a 40 HP, easily with a 50 HP, and anything beyond that is bonus. I got a 90 HP so I can tow a tube or water skier, but otherwise it's plain overkill as this is not a speed demon hull design (see Rampage or Renegade for that).

However, there is at least 1 other Malahini owner with a a newer 75 HP motor that probably has the same weight range and is doing fine. I'd look at shifing your battery and/or fuel tank forward for the sake of balance.
Ian (aka Iggy)
My Malahini Build

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rbrandenstein
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Re: Malahina with Mercury 75 HP 4 stroke

Post by rbrandenstein » Tue Jan 15, 2013 12:19 pm

JL.
I did a bunch of research on engines for my Malahini. My wife wanted a 4-stroke since they are more quiet, but used ones are hard to find and also expensive. I noticed the same weight issue on the new Mercurys and was surprised the 2 stroke was almost the same as the 4 stroke. This weight was a concern so I ended up buying an older 65HP Mercury 2 stroke, but some day may want to upgrade.

In general, all the 4 strokes are in this weight range. You can also get a 90HP for the same weight as most share the same block.

One engine to look at is the Evinrude E-TEC. It is a two cycle, but seems very advanced, quiet and reliable. I think they weigh around 320#. JeffH and Darthplywood have these engines and I think give them high marks.

Good luck.
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jlwright
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Re: Malahina with Mercury 75 HP 4 stroke

Post by jlwright » Tue Jan 15, 2013 1:20 pm

I really want a 4 stroke if possible. I sent an email to the mothership asking for their advice. We'll see what they have to say.

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ttownshaw
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Re: Malahina with Mercury 75 HP 4 stroke

Post by ttownshaw » Tue Jan 15, 2013 2:01 pm

I have an Evinrude 70 2 stroke (237 lbs) and it pushes me along quite nicely. I understand the likely reasons why you would want a 4 stroke. Jeffh installed a 90 (which should weigh in around 320 dry) but I also believe he added a couple of additional knees. I was really shooting for fuel economy, weight/horsepower...all that jazz. Plus, price was a big decision maker as well.

Let us know what you decide.
Bill

I told my wife we needed a three-car garage for my projects...she told me to ask her for permission next time before I buy a house.
http://www.unitybuild.net

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jlwright
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Re: Malahina with Mercury 75 HP 4 stroke

Post by jlwright » Tue Jan 15, 2013 2:05 pm

I may have found the right motor. It is a YAMAHA 70 HP MODEL F70LA. It only weighs 260 lbs. and is a 4 stroke. Not sure how they lose all that weight. Does anyone have any experience with this particular model?

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jprice
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Re: Malahina with Mercury 75 HP 4 stroke

Post by jprice » Tue Jan 15, 2013 2:28 pm

I've had my eye on that one as well. Although I must admit, that I really do like the sound of the e-tecs.

I would love to know what yamaha removed to make it so much lighter than every other comparable 4-stroke in the industry.
...sounds like magic. :lol:

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jeffh
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Re: Malahina with Mercury 75 HP 4 stroke

Post by jeffh » Thu Jan 17, 2013 9:22 am

Hello Lads,
It has been a few months since I've been on here. I see this is a new thread, so I'll throw in my two penneth. I was also shocked by the weight of some of these engines. When I was shopping, I wanted a classic engine but then my wife spoke up and said she did not want to hear me whining about maintenance and power and said to look for something new or almost new (imagine that...me whining). So I set my desires on 75-90HP like most of you...I would have also taken a 60. The 4-strokes were all definitely heavier and if you're looking for new, there really are no true 2-strokes anymore (I'm not sure what the deal is with the Yammy 2-stroke). The E-Tec and the Optimax are 2-strokes but nothing like the super lightweight 2-strokes you could buy a few years ago. The new ones are all loaded up with computers and direct injection now that add weight. Mine does weigh 320lbs and I added two really large knees on each side with strongbacks running up to the frame for piece of mind. I also moved my fuel tank to the front and I think that helps. Unlike a lot of people on the forum, I'm not very mechanical (as my wife pointed out) when it comes to engines. I wanted something that was easy to maintain. But I did install it and wire it all by myself (I used a shop crane from Harbor Freight). The E-Tec does have to be programmed by a certified E-Tec shop. Once I started reading about E-Tecs and their maintenance and performance, I started looking for one. As far as smoke and noise, my 2007 ETec is just as quiet as my 2007 115HP Merc 4-stroke and the same amount of exhaust smoke (both now have >150hrs). The E-Tec has cleaner exhaust emissions than a 4-stroke, it produces 5 to 10 times less Carbon Monoxide while idling or trolling. New E-Tecs can go directly into the water and run full throttle...they require 0 break-in. They also have a 3-yr/300hr maintenance schedule and then there is that torque and acceleration. My boat jumps out of the water and with the current prop runs in the 40s on good water. They have have a self-winterizing feature that I liked. Plus the white color looks kinda vintage :D Outboard engines are stupid expensive though and I was once told that when going >200HP, it is more practical to go with an inboard but that is not our concern on Malahinis. I still paid about $4500 for my 2007 2yrs ago and that was about 1/2 price. Okay, so we've determined I like it :lol:
Specs:
E-TEC 90 = 320lbs: in-line 3 cylinder: 79 cid/1295cc
Yamaha F90 = 380lbs: In-line 4 cylinder DOHC: 97 cid: 2.31:1
Yamaha 2-stroke 90 = 261lbs: In-line 3 cylinder: 69.6 cid: 2.0:1
Merc Optimax 90 = 375lbs: In-line 3 cylinder: 92.96 cid/1526cc: 2.33:1
Honda 90 = 359lbs: In-line 4 cylinder SOHC: 91.47 cid/1496cc: 2.33:1
Suzuki 90 = 341lbs: In-line 4cylinder: 91.7 cid/1502cc: 2.59:1
2011 MALAHINI - KICKED IN THE HEAD
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I wake up with a 16ft woody every morning :)
Video: http://www.youtube.com/watch?v=534DBtp1Cnc
Website: https://sites.google.com/site/2011malahini/

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ttownshaw
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Re: Malahina with Mercury 75 HP 4 stroke

Post by ttownshaw » Fri Jan 18, 2013 12:14 pm

Great post Jeff...I was hoping you'd chime in.
Bill

I told my wife we needed a three-car garage for my projects...she told me to ask her for permission next time before I buy a house.
http://www.unitybuild.net

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