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Several have suggested Mercury to repower a 150hp 1979 Outrage V-20 - max rating 175hp. Having spent most of my life in the sailing world, I find the Mercury options confusing.

Listers and reviews like the four stroke 150, but the website also has a ProXS 150 ProXS, a Seapro Four stroke 150. and a ProXS 175. The double pro has the highest max rpm, Seapro 150 the lowest max rpm, and the 175 appear to be a two stroke with the lightest weight and oil injection.

For general salt water use, price, and not concerned with top speed, is the four stroke 150 the better choice? Or just go with the one with the best deal?

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Cy,

As you might have guessed from my posts in your other thread, I like these Merc "Fourstroke" offerings. What Merc has done in the past few years with these engines is very impressive. They have knocked down the weight, while increasing displacement, and simplifying maintenance. In some cases, Merc's Fourstrokes are now the lightest available option in several particular HP-classes, including 2-strokes. The old days when 4-strokes were always heavier than 2-strokes are history now.

Merc also has a line of "ProXS" engines, that are billed as high output or high performance models in their respective HP class. Until recently, the ProXS models were 2-stroke engines. But a year or two ago, Merc began transitioning the ProXS line-up to 4-strokes, beginning with the 115 ProXS Fourstroke (based off the standard 115 Fourstroke model.) This year they have added the 150 ProXS Fourstroke (discussed below) and many anticipate this trend will continue with the higher HP ProXS engines in the coming years.

The Merc 150 Fourstroke offerings can be a bit confusing at first. There are three versions sold in the U.S. (and yet another version sold in the U.K. under the Mariner label), all based on the same 3.0L I-4 powerhead:

1) The SeaPro version is a slightly de-rated 150 Fourstroke primarily intended for commercial use. It has heavier duty motor mounts and a lower WOT rpm range (4800-5300).

2) The standard recreation 150 Fourstroke has a WOT rpm range of 5000-5800. This engine has been out for about half-dozen years and has an outstanding reputation for reliability and for being powerful.

3) The just-released 150 ProXS Fourstroke is a new high output variant with a higher max rpm range (5200-6000) and some other ignition tweeks to boost mid-range performance. It uses a different gearcase with lower water pickups and a different gear ratio.


Tough call on which version to recommend for your boat. But I think you can leave the SeaPro version out of the mix (it comes with less warranty, I believe, because it's intended for commercial use.) I have a Yamaha on my transom, but hope to hang the 150 ProXS Fourstroke when the time comes (my boat is the 19 Outrage II with max hp rating of 150.).

And not to muddie the waters any farther, but Merc has just released a new line-up of 3.4L V6 Fourstrokes in the 175/200/225 range. These engines are the lightest available in their HP class, even when compared to 2-strokes. In my opinion, the new Merc 175 Fourstroke is probably the ideal repower solution for an Outrage 20 (if budget permits.)

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Thanks JRP you started me down the Merc rabbit hole. I was trying to make the Seapro 150 into a a special saltwater version with extra corrosion protection.

$10K seemed affordable and I could do more, but don't want to go up to the mid teen E-tecs. The Suzuki 140 would probably meet all my needs but if Merc offers a better engine for a little more... Need to see what the northeast dealers will do for me.

Showing my ignorance, has anyone installed a new engine themselves or does that void the warranty? I have done car and plane engine R&Rs, and have a tractor for the heavy lifting. I do have a nearby shop that Mercury lists as service only, I will see what they have to say.

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Downloading the Mercury spring catalog the 175-225 are called Fourstroke, the only 150 is the ProXS, and the SeaPros are 15 and 200. Different from their website.

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I re-powered my 21' Not A Whaler going from a 1999 135 Mercury Optimax to the 150 Mercury 4 Stroke and couldn't be happier. 2 stroke to 4 stroke, 6 Cylinders to 4, Larger displacement, almost the same weight, no 2 stroke oil to deal with. The boat tops out easily 10 MPH faster using my existing stainless prop, runs quietly, and the motor is a breeze to maintain. A bonus for me was my existing gauges and controls could all be re-used via a 'digital' adapter that plugs into the harness. I can always upgrade the controls later.

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Many have done repowers individually, you just need to take it to a dealer to verify install and warranty activation.

Check with your dealer before you buy the engine. Some dealers do not do activations on engines they don't sell.

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I purchased a Mercury 150 HP Fourstroke loose from Jaco's and had it delivered to a local dealer who hung the motor. I took the boat home and did a complete rerigging and hook up of the engine, then had to return to the dealer for a PDI to initiate the warranty. Doing so was satisfying, money saving and familiarized myself with the boat and rigging.

You can read about it here, including the performance report.

http://www.whalercentral.com/forum/vi...rowstart=0

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I’m going into my fourth season with my mercury 150 four stroke on my 1989 20’ Outrage. I cannot say a bad thing about it. Sips fuel. I have the eco gauge which is real nice and helps you set trim and throttle in synch for long runs and fuel savings. Good luck. Feel free to reach out with any questions.

Stephen

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Cy, I believe the "catalogue" you downloaded is only showing new releases introduced this spring at the Miami boatshow. The standard Merc 150 Fourstroke remains very much available. And yes, the new 3.4L V6 engines (175/200/225) are the newest members and share the "Fourstroke" family name.

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Hard to say no to a Mercury after those comments and PRJ's history. Glad to see there are purchase options.

Gauges. Currently I only have a volt and RPM gauges, probably as old as the 1990 E150. There is a 20+ year old Humminbird display above the console that showed depth last time it was out.

What minimum set of Mercury engine gauges should I start off with versus adding later? Not worried about NAV yet.

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Personally, I would just get a tach, and then a decent GPS / fishfinder - most of them can be connected and set up to show all the data you'll ever need.

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I'll be interested to hear gauge recommendations from those who have the Merc 150 Fourstroke. But in studying it, I've been intrigued by the Vessel View Mobile option:

https://www.mercurymarine.com/en/us/g...ew-mobile/

Not having done any number crunching, would it make sense to invest in a small dedicated tablet to display the Vessel View?

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My brother bought trawler in Trenton, Ontario and we spent most of that summer moving it to the Chesapeake. It had a Standard Horizon 1010 in the main cabin but he liked to steer from the flying bridge. We used our phones and my old Nexus 7" tablet for the whole trip. Open Cpn is a free app (on my Android) that uses free NOAA ENC charts.

Easy to do from a fly bridge, will have to 'bag' it on the Outrage to stay dry..