wondering how the 3.0 merc 165 would perform on a 20' boat

jwilkey84

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I just saw a boat for sale that caught my eye. It is a 20' open bow with a 3.0 merc, which they said was 165hp, how would that perform on the water? Would it be plenty of power? I wonder how fast it would go?
 

Laddies

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

You have posted in the outboard forum, you will get more answers in the I/O forum. If the engine is a 4cyl. 165 HP it is a engine that was built by Mercury and after a few years went out of production it was 3.7 Liters and troublesome I would not get involved with it. Not many shops will even take them in for engine work other than a tune up.
 

starsnstripers

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

Well that depends on the price, yr., and what shape its in? The hp is fine i have a 21' 1970 with 165hp it's a straight 6 but it came stock that way at 4700lbs 30-40 mph depending on hull, tuned and proped correctly. I'd worry more about what shape it's in than the engine size. Good luck on it let us know.:D
 

Don S

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

Well that depends on the price, yr., and what shape its in? The hp is fine i have a 21' 1970 with 165hp

There is a 4 cylinder 165, and a 6 cylinder 165. The 6 cylinder was a great engine, the 4 cylinder (aka 470) were/are, how should I say this, less desirable than the 6 cylinders that were not used after 1981.
Since he called it a 3.0L, I would guess it's the 4 cylinder.
 

starsnstripers

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

Yeah i figure he's talking 4cyl too. My point was he has alot more to look at than the hp. And by the sounds of it the 3.0 4cyl. hasen't been bragged about to much. All i've seen on here if it's a 470 beware. I'd say keep shoping. good luck !;)
 

jwilkey84

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

I was just curious because I thought I had read somewhere that a 3.0 liter was 135 hp, not 165. I don't know much about I/O's, but one would think that a 165hp outboard would push a 20' boat pretty well, so I was wondering how the I/O would compare to the outboard for speed and power. My father had a 21' deck boat with a 125merc outboard, and it would pull two skiers pretty well, so I figured a 165 would do even better. If someone could fill me in on the differences in a outboard and an I/O I would appreciate it. How do they compare in weight related to horsepower, fuel economy compared to an outboard, and ease, or lack thereof in self-maintenence. I think they might be nice on my next boat because they are not in the way as much as an outboard. I am just trying to weight the pros and cons of each and determine what I want.
 

watermellonI

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

You can get the power and durability out of both worlds with proper maintence and care.

What I like about an inboard engine is its quieter and out of your way, usually below decks or under the euro hood.
 

ziggy

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

ya should find out what it is... 3.0 or 165. if 165 find out 4 or 6 cyl. if it's a 165 4 cyl. better check it our realllll gooood.... some like it, most don't... if it's the 6 cyl. one. everyone likes that one... if it's really the 3.0 most folks like that too. just a shade underpowered usually are the comments....
 

jwilkey84

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

I have found another boat that has a 3.0 135hp motor. Are there a lot of complaints about this motor also? It is a on a 1996 crownline that is 17' long, I figure 135hp should move a 17' boat pretty good. Just wondering if this a motor that typically most of you gearheads would recommend.
 

JustJason

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

if you want to know more about the pro's and cons of the 3 major engine configurations (outboard, inboard, and I/O).... start a new thread!!
 

Bondo

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

I have found another boat that has a 3.0 135hp motor. Are there a lot of complaints about this motor also?

Nope,....

The 3.0l motors are 40 year Proven preformers.....

Underpowered if in a hull bigger than about 19' or so,....
But Proven Reliable motors.....
 

Bry21317

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

Crownline Makes an awesome boat. I have one that is a 94 19 ' Model. I love it. I upgraded to this from a Bayliner. I also have the 5.0 Liter V8 in it though. But it is great.

I have a buddy that has a 3.0 in his 18 Foot Galaxy boat, and it will run about 45, and he can keep up with me in my boat, pretty decent. I can run 50 or a little over but he can hold his own for a 4 cyl.

Bryan
 

cosborne

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

I have a 1996 Bayliner with the 3.0L Merc, but I do not remember if it is the 135hp or the 165ph. It is a Capri 1950. The fastest I had it was 40mph. I like the motor and it runs good. It also gets good gas mileage. I just wish it went faster.
 

Don S

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

I have a 1996 Bayliner with the 3.0L Merc, but I do not remember if it is the 135hp or the 165ph.

It's very simple. There is no such thing as a 165 hp 3.0L, it was a 3.7L Motor, not a 3.0L. They just assumed (dumb thing to do) that since it's a 4 cylinder engine, that it must be a 3.0L Gm engine. Wrong. The 3.7 is a 470 syle, Mercruiser designed aluminum block with a Ford 460 head on it and a charging system built like an outboard, only with a raw water cooled regulator along with only a 3" heat exchanger, BUT WAIT, there is more............. Never mind.
It was a design that didn't work.
 

rob935

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

the 3.oL mercruiser is a basic 135 h.p. with a variant up to 145h.p but all this is relative to the weight of your boat, i had an 18 ft wellcraft with a 3.o merc and it was sluggish at best and needed to stay at high revs while skiing, this is very hard on the engine and i have seen many 3.o mercs give endless trouble due to this fact,

my advice would be to go for a boat with a 4.3L merc or volvo may be a little more expensive but will work out cheaper in the end .
 

dcg9381

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Re: wondering how the 3.0 merc 165 would perform on a 20' boat

the 3.oL mercruiser is a basic 135 h.p. with a variant up to 145h.p but all this is relative to the weight of your boat, i had an 18 ft wellcraft with a 3.o merc and it was sluggish at best and needed to stay at high revs while skiing, this is very hard on the engine and i have seen many 3.o mercs give endless trouble due to this fact,

my advice would be to go for a boat with a 4.3L merc or volvo may be a little more expensive but will work out cheaper in the end .



I 2nd this. Family has owned 2 x 3.0L powered boats.. And I've played with a friends. For low occupancy, cruising, it's a good reliable motor.
Not fast, but reliable and reasonable.

If you're going to ski with more than about 2-3 people in the boat, it's tough.

Even empty, single occupant, 18" boat, If I sit, I can keep the boat from going to plane if they're trying to pull me out of the hole.

Depends on what you're going to do with it, but if you're going to use it for skiing or with water toys, get a 4.3L.
 
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