Anyone powered with a 3.0 140hp recently?

B

brisboats

Member
I am considering pulling my 3.7 165hp and putting in a much newer 3.0 LX 140hp. Nothing against the 3.7 but I really like the simplicity of the 3.0 liter. I am going to use the boat for a crabbing boat and think we can pick up a bit more mpg's too. Not really looking for top speed obviously, but need to know that she will plane with a 1,000 pound load aboard.

I have done plenty of repowers and swaps so aware of the different outdrive ratios and the small things that will arise. My main concern is that the boat will be a poor performer. Reality is I am a firm believer in the if it works don't fix it mantra. But we just got a few low hour 3.0 alpha one gen 2 powered boats and I would like to switchover while these powerplants are still available.

Brian
 
I've wondered about this as well since the 3.0L even brand new is a good price(used to be about half what a 140 4 stroke outboard was). I would think the performance would be pretty good as the ALPHA would let you swing a large diameter prop or even a 4 blade which would give you good bottem end planing.
 
Looks like I may just give it a try. I'll be sure to take some pics. If the performance is so lackluster I cannot live with it I'll pull the 3.0 and throw in a 4.3 or bigger. By then the temps should be high enough to do glass work I am avoiding by going with a inline motor.

Brian
 
A 3.0 140hp produces about 180 lb-ft of torque, and a 3.7 165hp produces 250+ lb-ft of torque. A huge difference in a boat.
 
That is a good point no doubt the 470 has more torque than the 3.0. But it also is made from two dissimilar metals, has a water cooled voltage regulator, a prohibitively expensive manifold and riser, a stator that likes to fling magnets, weighs more, idles like a tractor, etc. etc. :-). I am leaning towards the 3.0 because it is available, much newer, cheaper and easier to maintain, will use less fuel, lighter. The biggest con is the power and was wondering how a 3.0 actually performs in the V-20. Looks like I will need to install one to find out.

Brian
 
Years ago I had a 19' Bayliner Capri with a 3.0. If I remember correctly, that boat flew in the water. You can always add tabs to help plane, if that is hard with all the extra weight...You will have the best of both worlds.
 
i look at it this way mercruiser stopped producing the 3.7 motor . but still makes the iron 3.0 liter . a little less steam but a bullet proof motor. the1:98 gear ratio and a 17p prop may put you close enough. i myself like more steam since i have a aluminum top and full enclosure. good luck with your project . please let us know how you make out!
 
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