Suzuki 100hp or merc 115hp cat repower

[Skusto]

Hey all

So looking at repowering a 2100 kevlacat, and can’t decide which engine should go for the suzuki 100hp is the lightest but the mercury are more power plus counter rotating.

The Suzuki’s are lovely engines and I think they would be better on fuel but I am also worried whether or not I would be wishing for a little more power or if I could still plane at low revs.

Also I feel resale wise if we were to ever sell that the Suzuki’s May sell it quicker.

So thought I would post here to hear people’s thoughts??

Cheers

[Flex]

I’m fairly sure the 115 Suzuki is available in CR box.
The 100,115,140 are all the same block and weight nearly the same
2100 is rated to 115? The 140 Suzuki is the pick as it weighs the same but if that’s overrated HP then 115 Suzuki is great choice.

Having said that, the latest mercury engines are fantastic bits of kit. But unfortunately they don’t hold same reputation here as they do over in the states.


Sent from my iPhone using Ausfish forums

[Skusto]

Hey flex

The only thing about the suzuki 115hp and why it’s off the list is they are around 185kg each from memory.

The current motors only weigh 140kg or there abouts.

The suzuki 158kg

And merc 165kg

Which is what makes it a hard decision.

Also the pricing of both merc and suzuki is pretty much the sane

[swof63]

The zuk 100b is a 1.5l motor, the merc is 2.1l motor. The merc will have better low/midrange torque which may be a contributor to staying on the plane at lower speeds. Only 8-odd kg each between them.


Sent from my iPad using Ausfish forums

[up the creek]

at the end of the day its what u want most, if thats low speed torque/ planning ability, and the suz cant do it as well, i dont know that youd have to figure that one, then the merc is the go, resale is important but you own it now and it has to do what u want and are happy with or its no use taking it out, im sure a couple of well looked after mercs wont hurt resale too much..

[lethal098]

Go the merc for sure, great little engine and outperforms all the others, Fuel will be close enough to identical,

[gazza2006au]

At this stage u really need to do some research and a bit of crystal ball reading into the near future (next 2-4 years) as the carb two strokes are being phased out people will only have the option of a lean two stroke or a 4 stroke and what u don't want is to buy a couple brand new engines that the market will be flooded in the near future as your resale value will greatly diminish

its kind of like those new Ford Trucks you know those big rangers... every man and his dog bought one so in 10 years they are going to be selling worse than a Ssangyong Chinese car's

if it were me i would go based on the above post 2.1L engine vs 1.5L as the yanks say u cannot beat cubic inch, in a horse race u can either ride a stallion or a donkey

[Noelm]

The zuk 100b is a 1.5l motor, the merc is 2.1l motor. The merc will have better low/midrange torque which may be a contributor to staying on the plane at lower speeds. Only 8-odd kg each between them.


Sent from my iPad using Ausfish forums
isnt the 100/115/140 Suzuki 2.04 litre (almost the same as the Merc)

[Flex]

Is there a new model 100 Suzuki? Is it based on the 90hp block?

Because most websites I look at have 100a same as 115,140.

A lot of 2100 runs 115 suzukis/yamahas from what I’ve seen?

Do you run far offshore? If your running along way with big loads then you’ll want the speed of larger block engine.

If your running in close the lighter one will be perfectly fine


Sent from my iPhone using Ausfish forums

[Noelm]

Hey flex

The only thing about the suzuki 115hp and why it’s off the list is they are around 185kg each from memory.

The current motors only weigh 140kg or there abouts.

The suzuki 158kg

And merc 165kg

Which is what makes it a hard decision.

Also the pricing of both merc and suzuki is pretty much the sane
if the 100 Suzuki weighs 158KG, it must be based on the 90.

[Skusto]

Yes they have two 100 these days one based off the 90 and one based off the 115.

Decisions decisions, cheers all. Will keep thinking. Have a buyer for the two strokes so will be pulling them off this weekend and start looking I suppose..

[BigE]

Suzuki will spin a much larger prop due to the gear ratio which I think would be helpful to a cat for load and low speed planning.

BigE

[gazza2006au]

The Mercury 115hp is based on the 75hp block and they don't mention the CC or cubic inch for some reason possibly because its a small engine perhaps? Zuki is based on there 70hp block.. maybe u could buy the 70hp cheaper and have the computer remapped i cannot see any difference in the motors from 70hp to 100hp other than there prices

also the Suzuki looks to have a second reduction gear set which means one more thing to wear out

Buy a Honda they pioneered the modern four stroke outboard.

[Noelm]

Actually the 70/80 is based on the 90, not the other way around, not too sure about a simple ECU rework to get the added HP, the reduction gear serves two purposes, to move the powerhead forward for better weight distribution and to increase prop size. Still can't see a 100 listed with the same specs as the 90, only the 100/115/140 version, but I didn't look too hard.

[Greg P]

Couple of pro xs 115 Mercs with command thrust legs would be the pick of that group. In the US Suzuki do a DF115SS which is a suped up version to compete with the pro xs. To bad we can’t get that here.

[robcam]

Actually the 70/80 is based on the 90, not the other way around, not too sure about a simple ECU rework to get the added HP, the reduction gear serves two purposes, to move the powerhead forward for better weight distribution and to increase prop size. Still can't see a 100 listed with the same specs as the 90, only the 100/115/140 version, but I didn't look too hard.

https://www.suzukimarine.com.au/outboards/midrange/product/df100b

[myusernam]

The Mercury 115hp is based on the 75hp block and they don't mention the CC or cubic inch for some reason possibly because its a small engine perhaps? Zuki is based on there 70hp block.. maybe u could buy the 70hp cheaper and have the computer remapped i cannot see any difference in the motors from 70hp to 100hp other than there prices

also the Suzuki looks to have a second reduction gear set which means one more thing to wear out

Buy a Honda they pioneered the modern four stroke outboard.
No the 75 is a derated 115. The 115 is 2.1L. no replacement for displacement. Same generation as the awesome 150hp 3.0L. self adjusting ohc. Designed for home servicing etc.

[gazza2006au]

Ahh thanks for clearing this up fella's

[myusernam]

If you speak to jono from jb marine in ingham he has experience in repowering i think more than one kevlacat from zucs to mercs (was a dealer in both) with gains

[robcam]

Hey Dan, surprised your not putting a couple of white motors on it.Anyway I believe the truisms " no replacement for displacement" & "always go max horsepower", so another vote for the merc 115 pro xs. Plus its got a red stripe.(but I`m probably biased) :builder2:

[up the creek]

Hey Dan, surprised your not putting a couple of white motors on it.Anyway I believe the truisms " no replacement for displacement" & "always go max horsepower", so another vote for the merc 115 pro xs. Plus its got a red stripe.(but I`m probably biased) :builder2:

thats what id be puttin on it. as rob says, no replacement for displacement, and these are said to be awesome engines.

[Skusto]

Just to end this thread I have decided to go with some mercury 90hp command thrusts. I am driving down to Sydney this wkend to grab them the price was right for a pair of 2017 models with low hours saving a lot of money over new which makes it worth the risk.

Cheers Dan

[Noelm]

I am about an hour south of Sydney if you need anything.

[Skusto]

Cheers Noelm hopefully we will be all good but will keep it in mind. Going to tow the cat down so I can just bolt them on and package up the rest and leave again hopefully all goes well.

[Noelm]

Jesus pretty keen towing the boat down.

[BigE]

what Props come with the CT's.

I had a CT 60 and there was a bit of trial an error in getting the right props.
Still have a spare 4 blade in the shed from my CT 60 HP

BigE

[Skusto]

14x19p enertia current motors have 18p vengeance So hopefully being higher gearcase should be right time will tell.

And yes Noelm I know but easiest way as engine crane will be on back of Ute so don’t really have the room for everything should be ok I hope. Will let you guys know Monday.

[Skusto]

Bit of an update. Well I done 1800km in
31 hours including removing motors and accesories off the other boat and fitting motors to our cat. Was buggered when I rolled back home at 230am Monday morning.

Finished fitting off motors this afternoon and took them for a quick run and I am extremely happy with them so far. They plane low have plenty of grunt and the props seam to be just right, had a light load today of 3 people and about half tanks and they revved out to 6000rpm so I know they aren’t over propped at least. The big 14x19 emerita props hold the boat so steady it’s like a completely different boat!

The only thing I have noticed so far is the counter rotating motor seams to be using about 4lt an hour more cruising which I thought was a little odd??? Could anyone care to confirm or deny?

[Noelm]

I know its common for one motor to use noticeably more fuel than the other, there is thoughts that the different gear box on the counter to affect fuel use, but not exactly sure on that, my motors are both standard rotation, and the port motor uses measurably more fuel than the starboard.

[ericcs]

I know its common for one motor to use noticeably more fuel than the other, there is thoughts that the different gear box on the counter to affect fuel use, but not exactly sure on that, my motors are both standard rotation, and the port motor uses measurably more fuel than the starboard.

Just like your anode problem Noel, it's difficult to get 2 identical motors to perform identically!

[Skusto]

Took the boat for another test run today have finished install completely and took a pad to jot down some fuel consumption figures. Quite happy with the overall consumption off the quick glance but once we do some of our fishing trips we should get a better indication of range etc. anyway figures below.

RPM LPH SPEED L/KLM
3500 25 38km 1.52
4000 31 44km 1.41
4500 40 51km 1.27
5000 48 57km 1.18
6000 64 67km 1.04

Cheers Dan

[Lovey80]

Looks like the sweet spot is 4000RPM.