Information Stagnation - New Engine

[Keithb77]

I’m looking around for and researching a new outboard for my 3.3M SIB. With so many options and lack of experience with every model, I feel it is becoming increasingly hard to make a decision.

I have been enjoying my older 9.8 & 8.0 2 strokes and love their light weight. Yet, I feel like spoiling myself with something newer or maybe brand new.

I looked at a minty, low hour 2013 Yamaha F9.9 this week. Holy cow it was heavy. I’ll be lugging it around, in and out of my truck. On and off the transom. I don’t use a boat trailer for my SIB, so engine portability is a key factor. I have yet to look at a brand new Yamaha 9.9 yet will soon. I was informed that the new ones are lighter. I hope so. We’ll see. I’m a bit surprised that Yamaha has not gone to EFI yet. Still carbureted. Does anyone know why? Are they maybe planning EFI next year? Yamaha has a great reputation and strong re-sale value here in Canada. It seems that so many boaters on the ocean choose Yamaha around here. Its hard to ignore their reputation. The new 9.9 comes with a 5 yr factory warranty

I went to the local Mercury dealer yesterday. I looked at a 2025 9.9 EFI 4 atroke. It looked great. I picked it up and tossed it around pretty easily. The weight felt manageable compared to the 2013 Yamaha. The price is right. 3 year factory warranty. Made by Tohatsu if I am right? Anyone have any concerns with this engine? I’m hearing 24% better fuel economy over the same carbureted model. That’s considerable for longer range. The local Merc dealer has been pleasant to deal with. Professional and prompt when buying parts for my old Mercs.

Lastly a late model 2 stroke. Maybe a 15 hp Evinrude, Yamaha or Mercury. The last production years seem to be about 2000-2005 ish that were sold here in North America. I’d try and find the last generation of 2 stroke. It will be a challenge to find a low hour used one. I like the simplicity and weight of the two stroke. Yet, brand new (but heavier) 4 stroke with warranty is attractive.

I could also consider a brand new EFI Tohatsu 9.9 4 stroke. I’ve yet to view one.

Top speed is not a huge factor. Yet I’d like a bit more power for an extra passenger and gear. We have stronger river current here in the spring, early summer. 15 hp 4 stroke is out I think. Too much weight to lug about.

We troll and fish in freshwater lakes. We also zip about on local rivers and lounge on hot summer days, swimming & relaxing. I have run my son’s 9.8 4 stroke Parsun on his 3.3M SIB. It feels like it makes enough power for my needs.

Any feedback on my above comments, based on your experience/ownership is appreciated It may help me land on a decision.

[Pikey Dave]

General consensus is that you get more hp/kg with 2T. If you want to go new & EFI, then you’re going to need deeper pockets and a stronger back.

[Steve509926]

This week I briefly sibbed with a guy who was running with a 9.9 EFI Tohatsu on a 3.2 Honwave. Weight wise it fell between my 20hp EFI Mercury and my 9.8 2 stroke Tohatsu. It was very quiet like my 20hp EFI and didn't smell, unlike my 9.8 2 stroke. Performance wise, 1 up with only a rucksack (with I presume his lunch in it) it appeared to do exactly what it should do.
The big difference between my 4 stroke and my 2 stroke, irrespective of hp, is that the 4 stroke EFI will "tick" over and push the sib along at 1.5 - 2 knots without a hiccup
The 2 stroke Tohatsu won't do that, it needs a bit more revs to stop it from stalling.
Fuel wise, for my type of sibbing - 14 knots, the 20hp EFI is much more efficient than the 9.8 2s Tohatsu.
I think weight is very subjective. I can still cope with my 20hp (47kg) EFI - just! but I'm well aware that in 2 maybe 3 years time it may be a struggle. I'd like to think that the 37kg of the 9.9 EFI Tohatsu wouldn't be a problem, but I'm fortunate enough to have a very late, little used 9.8 2s Tohatsu to fall back on, which weight V performance is excellent.
If I was in a position that I needed to "downsize" from my 20hp EFI, I think it would only be for 3 OB's - a late 15hp 2s Yamaha or 9.8 2s Tohatsu (fortunate to already have) or a new 9.9hp 4s EFI Tohatsu

[Keithb77]

Thanks Steve. I have had a previous back injury and its never been the same since. I can function ok I just need to be cautious and go lighter. Especially as I age. My 3.3M SIB is about as big as I’ll ever own. Its rated for 15 hp. Bigger SIB just means more weight to lug around. So a 4 stroke 20 hp is definitely out. I also hear the 15 hp 4 stroke weights the same as the 20. So its out too.

Back when I 20 yrs younger I had a 4.2M or so SIB with a 2000 yr 25 HP 2-stroke Merc on it. I dragged it around fairly easily but dang, it was heavy enough. I swore to myself this time around I’d keep it light. Yet here I am upping from my current 29 kg 2 stroke to. 4 stroke. That 25 HP Merc was like a low flying jet. It was fast! If I recall it weighed about 56 kg.

At 54 yrs old today, this next purchase is ideally a 10-20 yr commitment for me. At some point a boat trailer is inevitable.

[Steve509926]

Originally Posted by Keithb77

Thanks Steve. I have had a previous back injury and its never been the same since. I can function ok I just need to be cautious and go lighter. Especially as I age. My 3.3M SIB is about as big as I’ll ever own. Its rated for 15 hp. Bigger SIB just means more weight to lug around. So a 4 stroke 20 hp is definitely out. I also hear the 15 hp 4 stroke weights the same as the 20. So its out too.

Back when I 20 yrs younger I had a 4.2M or so SIB with a 2000 yr 25 HP 2-stroke Merc on it. I dragged it around fairly easily but dang, it was heavy enough. I swore to myself this time around I’d keep it light. Yet here I am upping from my current 29 kg 2 stroke to. 4 stroke. That 25 HP Merc was like a low flying jet. It was fast! If I recall it weighed about 56 kg.

At 54 yrs old today, this next purchase is ideally a 10-20 yr commitment for me. At some point a boat trailer is inevitable.

I'm similar to yourself with a glass back held together by a chiropractor, osteopath and a witch doctor with cortisone, but that's where the similarities stop, I've 10+ years on you!
If I was in your position, if you can't source a late, mint 9.8/15 hp 2 stroke, I'd seriously look at a 9.9 EFI Tohatsu (or Merc slightly heavier) At 37kg - yes it's heavier than you currently have, but it will probably do what you expect of it.

[Fenlander]

It is very easy to beat yourself up over there being something better, lighter or more powerful than what you have or what you are thinking of and end up going in circles trying to get that sweet spot.

Here is how I went round those loops. Oh must mention I hurt my back 25yrs ago lifting farm machinery so have been wise about carrying since.

Going back some 10-15yrs I had several different SIBs in the 3.4-3.8m range but always used a 15hp 2-stroke, first a Mariner and then the identical Mercury model both being a manageable 36kg. Since then I've had the same 3.8m SIB for ten years and all the outboards mentioned below have run on that same SIB.

When the two girls became teens I wanted a bit more power for all four of us together and bough a new Suzuki 20efi with a claimed 44kg but more like 46kg when filled with oil and a prop fitted. This needed careful lifting and was made more awkward by being super bulky compared to the 2-strokes. It was quiet and good at slow trolling, easy on fuel too.

Then several things coincided... daughters stopped holidaying with us, wife became less able to help me move it, I was suffering a shoulder/neck issue and then the last straw I had a reliability issue which lost me confidence. I traded it for a new Mariner 9.8 4-stroke carb model weighing 37kg which I planned to keep for years.

This was an unexciting but workmanlike motor which we used for a while until it suffered a near breakdown at sea causing me to return to what had served me so well in the past, a 36kg 15hp 2-stroke (Yamaha this time). 50% more power and greater simplicity for slightly less weight was a good deal.

Annoyingly my neck continued to play up and even the 36kg started to be a struggle. So I sold the Yamaha and bought a SIB known to go well with smaller engines plus a 27kg Tohatsu 9.8 2-stroke to go with it. The Tohatsu was a dream to lift about and performed well. However the new SIB wasn't to our liking so after the sea trial we sold it and reverted to the original 3.8m using the Tohatsu. Its performance was just acceptable on the bigger SIB but less than ideal.

By chance physio sorted my neck/shoulder issue so I bought another used 15hp 2-stroke, a 35kg Johnson. This had a ticking time bomb left by the previous owner and failed on the first outing so I scrapped it and bought a much nicer Yamaha 15hp 2-stroke. It's this motor that's just powered us for a week's holiday. There is no doubt any of the 15hp 2-stroke models around 36kg are our sweet spot. I have kept the light Tohatsu for occasional river use and when there may be a period when I really can't manage a 36kg motor but don't feel quite ready to give up. I'm 70 next year so the time will inevitably arrive.

Hope that gives you some ideas.

[Keithb77]

Good thought provoking comments. I appreciate it.

I went to the local Yamaha dealer today. Checked out a new 9.9 4 stroke. I’m not happy with the weight. I did some research on late-model tohatsu 9.8 2-strokes. They seem to be the magic one that is the right weight/hp ratio. Looking at my local on-line classifieds there are a couple of them in my region for sale. Labeled as Nissan, made by Tohatsu. I also see an 18 hp 2 stk Nissan/Tohatsu. Interesting for sure. Pretty far drive to get to them though. Be an overnight trip to check one out. I have asked sellers to send me compression measurements. If they are decent I’ll consider them more. If they can’t/won’t provide, I’ll pass.

[Steve509926]

Hi Keith, take a look at the two videos in this thread I did a couple of months ago.

https://www.rib.net/forum/f50/west-c...est-91966.html

The red Aerotec with the red canopy is running with a Tohatsu 18hp 2 stroke (ignore the 9.8 hood, he cracked his original hood) it is very fast and has loads of get up and go! I've personally never lifted it so I can't comment on weight, but the guy who owns it Big Al (irony) never appears to struggle with the weight.

[jonp]

I recently bought another little boat which has a 2020 Yam 15 2 stroke, last one before being banned here in Australia.

I believe it to be the same engine as the 9hp, which can easily be changed to 15hp at a very low cost.

The Yam 15 2 stroke is extremely sought after due to its simplicity and reliability, hence why I bought it. Have a look here for the detailed review on the 15 https://www.tradeaboat.com.au/news-r...table-outboard