60hp vs 75hp for 160ss

[Moserkr]

Hey Starmada!

The lakes n rivers are full out here and winter is still coming! Currently in a blizzard and expecting 3-7’ of snow!! Thank the Lord I didnt try to restore my boat this year - the winter I chose never saw a foot of snow. We have feet on the ground already and its cold!!

Its been a while since Ive worked on my boat or motor, and it has become apparent to me what I have more of - its not time. I love the old 2 strokes but mine have seen better days. I dont have the time to learn how to and then actually fix them. No one locally will work on a 40 year old motor either so cant throw money at the problem. After talking with the Admiral, she has come to like the idea of putting the cherry on top of a full boat rebuild - a brand new motor. There will be lots of full lakes to enjoy this year.

Ive been doing some homework and out of the big 3 - honda, yamaha, and mercury - Ive narrowed it down to wanting a mercury. The 2 biggest selling points? Local dealers that actually called me back, and maintenance free valve train. The yam’s n honda’s need valve adjustments to function well and the dealer service centers here are few n far. Mercury is also offering a 5 year warranty right now - 2 more than their standard 3 if bought in the next 30 days.

So, hearts really set on a merc. Question then is, does a 75hp really offer that much more than a 60hp? Im leaning heavily towards the 75hp. My biggest thing is getting up on plane fast - a good hole shot. We are usually loaded down pretty heavy, and Id like to use the boat for water sports - tubes n skis. The 75hp not only has more hp, but significantly more displacement. With the right prop, I can see it pulling out of the water well. Not concerned with top speed much, both should do 30mph+ no problem which is plenty.

Not worried about price, fuel usage, or weight. The new transom can handle the 100lb weight difference, and will actually benefit me I think. I shifted 100lbs forward when I put my 19g fuel tank towards the front. The boat rides slightly nose forward with the current 250lb motor on back and a full tank of fuel up front. So constantly having 100lbs off the back would rebalance her well in my mind. I could also move batteries to under the consoles from the rear, or put in lithium, to shift or save weight.

I wish I could slap a 90hp on the back but the coast guard rating is 85hp, and my insurance will drop me for going over that rating. Bummer. But seeing as how the 75hp is a tuned down 90hp, and with me living at altitude, I hear the air restrictor can be removed to squeeze a few more horses out of the 75s…

So those are my current thoughts. Most of y’all have been around boats far longer than I have so Id like some other opinions. Plan is to make the call within the next 2 weeks. A new motor would be here around the time the snow melts. Would get it installed and on the water right as summer starts warming up!

Thanks everyone,
Scott
Aka Moserkr

 

[DLNorth]

I've related our experience before but...
We have a SS16 that I put a 850 Merc on (4 cyl 2 stroke), later versions are 75 hp prop.
We bought the boat because my buddy had a SS16 but with a 70 OMC (powerhead rated) which was was rated 60 prop in later years.

So he had 60 prop, we have 75 prop.

With 3 guys in his boat, it worked a bit to get a skier out of the water, with ours no problem. Our boat is noticeably faster also, though I don't have any numbers to quantify it.

So, if you think you will have a light load, 1-2 people and small people skiing, 60 prop would work BUT if you think you will be loaded heavier and or larger people skiing, you will be happier with the 75 prop.

 

[Moserkr]

Thanks @DLNorth thats my thinking as well. Currently have a 75hp omc (powerhead rated). It has always been a bit slow to get out of the hole when we are loaded up. Top speed was decent. Pulling a tube was hard on her with a bunch of people. Id like to be able to pull an adult skier up with a bunch of people on board.

 

[racerone]

Get the correct prop for the 3 cylinder OMC.----Try a 15" pitch if it bogs with a 17" pitch.

 

[DLNorth]

Another thing you didn't mention but, T&T is night and day different then none. Don't know what you currently have, but if you don't have it, that along is worth upgrading a motor for. (my buddy didn't have it if I remember correctly)

 

[flyingscott]

If you are looking at the 3 cylinder Merc that is an excellent choice. The 75 omc will never be ideal for what you want to do.

 

[Moserkr]

Should add another poll option: Fly @racerone out to my place on an all expenses paid motor rebuilding / education vacation. Would cost as much as a new motor probably but then Id have 2 new (old) motors...

Appreciate you @racerone and your wealth of motor knowledge. Unfortunately my issues with the motor(s) are beyond just a prop change. My choice is spending a summer learning to rebuild old motors, or take the easy way out and put a new one on there. Easy way out gives me a summer of fun on the lakes with the Admiral and kids, instead of being alone in the garage. I was never raised around rebuilding anything so its foreign to me and I wish it wasnt.

@DLNorth My current motor (75 johnson) has TnT which is really nice. Definitely was not an issue there. Motor is tired - compression is fairly even but below where it should be.

@flyingscott Thanks, I agree, the omc has left me wanting more power. I have been looking at the i4 cylinder merc with 75hp. The 60hp merc is a i3 cylinder. Figure the bigger bore for more displacement and extra cylinder of the 75 would really make a difference.

 

[flyingscott]

How is the 75 a detuned 90 hp? That would only be on the 3 cylinder blocks.

 

[Moserkr]

The newer (2015+) merc 75hp is an inline 4 cylinder, and shares the same guts as the 90hp and 115hp. They just tune it down to make 75hp - same everything except lower rpms, programmed ECM, and an air restrictor from what ive read. Even read of people flashing the ECM to make it a 90 or 115. Go to merc’s website and take a look, Im pulling 90% of what I know from them. Heres a screen shot.

 

[SHSU]

I am sad to hear you are dropping the Stinger. I still like to tinker on my 1977 70HP Evinrude. But can't argue with going new. Wish I could justify the cost. lol

SHSU

 

[Moserkr]

@SHSU I wish I had the time to fix the old ones up. The old 2-strokes are nostalgic. I cant justify the time fixing them when my work and family is keeping me so busy. Same reasons make me justify the new one. Part of me wants to keep the stinger to work on it, but that will depend on what I get for the current motor on the boat when it sells.

Unfortunately I dont know any gear heads, or have much knowledge of motor work. My last 2 fixes on the motor ended up doing as much damage as I did fixing lol, and that was the simple stuff. But lack of time is really killing me. Top that off with a busted foot and a whole lot of snow - 7’+ and more coming! I can hardly stand to work as of now so Im way behind on so much already.

Other thing is altitude and efi is so much easier. I dont have to think about boating at sea level or 8000’ which Id like to do. Its been on my mind for a while and it kills me walking by the boat daily knowing that I have other things to do.

 

[SHSU]

I get that, I can't tell you how many trips we just puttered around because I couldn't get her above 2k RPM, but I guess I am stubborn and like to bang my head against a wall.

SHSU

 

[Moserkr]

@SHSU So far Ive only puttered around once where she almost failed to get me back to the dock. Usually its a failure to leave the dock lol. I just add up the money it takes for me to drive out and back, not have fun because its not working today. Doesnt take many of those trips to start adding up to a lot of wasted money. We only get so many trips out there a year and Im hoping to increase that number, as well as travel farther knowing we have reliability. Been tough to justify traveling to lakes further away when its a crap shoot whether we can actually use the boat.

Making my decision quick to take advantage of the extra warranty offer. Will see if it happens but Im trying. Controls, rigging, taxes…. Its getting steep!!

 

[flyingscott]

That clears it up