Reply
 
Thread Tools Search this Thread
 
Old 04 January 2012, 15:16   #1
Member
 
lightning's Avatar
 
Country: UK - England
Town: Marple
Make: Zodiac
Length: under 3m
Engine: Tohatsu 9.8
Join Date: Jun 2009
Posts: 601
Tohatsu 9.8 on my Zodiac 285

I have the opportunity to buy a Tohatsu 9.8 2-stroke engine

I have a Zodiac 2.8m SIB with a solid floor and air keel. At present I have a Mercury 6hp 4 stroke on it, and it's a good engine.
The boat will plane with two adults on board, achieving about 14mph on the GPS. However with three of us on board (rare) it won't plane.

The Tohatsu weighs the same (26kg) as my existing engine, and offers an extra 4hp. also it can be carried and stored at any angle. Is it a single or twin cylinder?

Would this be worth buying for my boat? I use it in various waters, from trolling on the canal to higher speeds on Scottish Lochs.

I was wondering if the Tohatsu would be more refined, as the Mercury is flat out when planing and also vibrates a bit through the tiller.

Will the Tohatsu 9.8 2 stroke sit at idle speed on the canal OK? And how is it for noise levels at lower speeds? On the canal we are generally at 2-4 mph which is about 1/4 throttle on the Mercury.
__________________

__________________
lightning is offline   Reply With Quote
Old 04 January 2012, 15:24   #2
RIBnet Supporter
 
willk's Avatar
 
Country: Ireland
Make: Redbay Boats
Length: 9m +
Engine: 370hp
Join Date: Feb 2008
Posts: 13,819
RIBase
They don't like idling for too long and need the odd "blip" to keep them running. I'd imagine it would HAVE to be noisier than the 4 stroke. They're a refined enough unit at revs - I don't notice any big vibration at close to WOT. At low speeds, they're not overly loud.

The performance should improve, especially the time to plane (hole shot). However, the extra 4hp won't make a massive difference to your top speed, but might mean that you can plane with three, on calm water.

With a similar SIB, my max speed was 18kts, one up, sweet FA on board.

Go on - buy it - you know you want to!
__________________

__________________
willk is offline   Reply With Quote
Old 04 January 2012, 15:46   #3
Member
 
Country: UK - England
Town: Winchester
Boat name: The Bandit
Make: Ribtec 535
Length: 5m +
Engine: Yamaha 90 2-Stroke
Join Date: May 2009
Posts: 433
If I where you I would, I bought one in the Autum and its great.
__________________
Ribtecer is offline   Reply With Quote
Old 04 January 2012, 16:38   #4
Member
 
SIBer's Avatar
 
Country: UK - England
Town: South Yorkshire
Boat name: Sold it !
Length: 3m +
Engine: Totallyhotsue 9.8 2S
Join Date: Sep 2011
Posts: 258
Details here
TOHATSU 9.8 HP 2-STROKE prices, specs, manuals and brochures.

Its a 2 cylinder and as its a 2 stroke you can lie it down anyway you like.
Its a bit noisy on low speeds but a bullet proof engine.
__________________
SIBer is offline   Reply With Quote
Old 04 January 2012, 17:28   #5
Member
 
Country: Ireland
Length: 6m +
Join Date: Jan 2012
Posts: 56
Highly reccomend the 9.8 tohatsu,i have one from new and will probably never sell it,currently pushes my Avon 3.1 tender with jockey console easily on the plane with myself and the youngfella at about19/20 knts.
__________________
moonshadow is offline   Reply With Quote
Old 05 January 2012, 09:47   #6
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: snagglepuss
Make: Shetland
Length: 6m +
Engine: 90 hp Outboard
Join Date: Nov 2011
Posts: 562
Hi

As a dealer for these engines we have found no problems with them and are great value for money.

if you are comming up to the scottish lochs you can always bring it in a drink camerons naff coffee why we check it over but I doubt it will need it.


However if you are pottering on the canal at 1/4 or less throttle I would stick with a 4 stroke.


Dave
__________________
clydeoutboards is offline   Reply With Quote
Old 05 January 2012, 10:17   #7
Member
 
Country: UK - England
Town: Sussex
Boat name: Bombard, Y-162
Make: Aerotec 380, Y-Class
Length: 3m +
Engine: Mercury Mariner 15hp
Join Date: Jul 2010
Posts: 3,016
I've got one so I guess I'm biased and agree with others here. Almost ridiculously simple engines to maintain and for the size very light. However, as others have said for canal pootling a 4 st may be better - running the Tohatsu at 2 - 4 mph it will be quiet enough - but up it to 6 - 8 (maximum displacement speed) it can get noisy.

WOT with 1.5 to 3 people on our Zodiac top speed varies but max is just over 17kts (20mph).
__________________
Max... is offline   Reply With Quote
Old 05 January 2012, 14:08   #8
Member
 
lightning's Avatar
 
Country: UK - England
Town: Marple
Make: Zodiac
Length: under 3m
Engine: Tohatsu 9.8
Join Date: Jun 2009
Posts: 601
Thanks for the advice.

It looks like the Tohatsu engine will not be ideal for the canal.

I think the best thing would be to have two engines, one for open water and a lightweight 4-stroke for the canal (maybe the Honda 2.5hp) which would be a fair bit lighter than my existing engine and plenty fast enough.
__________________
lightning is offline   Reply With Quote
Old 05 January 2012, 15:58   #9
Member
 
Country: UK - England
Town: Sussex
Boat name: Bombard, Y-162
Make: Aerotec 380, Y-Class
Length: 3m +
Engine: Mercury Mariner 15hp
Join Date: Jul 2010
Posts: 3,016
Beware - I think the baby Honda is air-cooled and not so quiet.
__________________
Max... is offline   Reply With Quote
Old 05 January 2012, 16:11   #10
Member
 
mister p's Avatar
 
Country: UK - England
Town: LONDON
Make: SR4/ZODIAC/3D
Length: 4m +
Engine: 30T/40T
Join Date: Oct 2011
Posts: 1,433
Very correct about the noise issue on the baby Honda
__________________
mister p is offline   Reply With Quote
Old 06 January 2012, 03:08   #11
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: snagglepuss
Make: Shetland
Length: 6m +
Engine: 90 hp Outboard
Join Date: Nov 2011
Posts: 562
Hi

i would hear the honda running before rulling it out, yes it is air cooled but this has been a plus and the noise never a problem when you hear other engines side by side.

The only downside for me is that Honda's always come with everything and the longest warranty but oh no. This engine comes in at 12.5kg for the short and 13.5 for the long but it does not come with a carrier/ shoulder bag! This is amazingly classed a an extra.

so as the mercury , mariner and Tohatsu's are the same for small engines the Tohatsu is also worth a look.
__________________
clydeoutboards is offline   Reply With Quote
Old 06 January 2012, 08:27   #12
RIBnet admin team
 
Poly's Avatar
 
Country: UK - Scotland
Boat name: imposter
Make: FunYak
Length: 3m +
Engine: Tohatsu 30HP
MMSI: 235089819
Join Date: Sep 2005
Posts: 11,040
Quote:
Originally Posted by clydeoutboards View Post
i would hear the honda running before rulling it out, yes it is air cooled but this has been a plus and the noise never a problem when you hear other engines side by side.
I used to have a 2HP air cooled Honda and at full throttle it was at least as noisy as my 20HP Yamaha 2 stroke... ...its not a pleasant noise either - but there are some advantages for canal running such as not having to worry about weed / plastic bags blocking the cooling water intake. I imagine the plastic prob and centrifugal clutch would also go a long way to protecting the gearbox from a shopping trolley strike. On the other hand transportation / storage of 4 strokes is a pain and I found that between this and extreeme sensitivity to angle of orientation when topping up the oil (to get it level in the sight glass) it would smoke more than a 2 stoke until it had been running for a while.

The Tohatsu 9.8 is a well liked engine. The only real benefits I can see from a small 4 stroke would be: lighter weight - but the tohatsu is not that bad; better fuel economy - but its not going to be a huge difference in terms of total litres per annum, possibly less likely to foul plugs on the 4 stroke - although I think that is possibly exaggerated from the old days of premix, and "add a bit extra oil to be sure", its also not the end of the world in a canal. Does that justify it compared to having a second engine to insure, maintain, winterise, etc?
__________________
Poly is offline   Reply With Quote
Old 06 January 2012, 10:21   #13
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: snagglepuss
Make: Shetland
Length: 6m +
Engine: 90 hp Outboard
Join Date: Nov 2011
Posts: 562
Hay Palwart

when am I servicing the honda? that sounds far to noisey compared to the one we serviced last week.

Dave

ps you can always drop it off at my place and grab a coffee as I am only in gartcosh
__________________
clydeoutboards is offline   Reply With Quote
Old 06 January 2012, 12:09   #14
RIBnet admin team
 
Poly's Avatar
 
Country: UK - Scotland
Boat name: imposter
Make: FunYak
Length: 3m +
Engine: Tohatsu 30HP
MMSI: 235089819
Join Date: Sep 2005
Posts: 11,040
Dave,

I flogged the Honda a while back. It doesn't fit on the back of this boat beside my main engine so was no longer useful.
__________________
Poly is offline   Reply With Quote
Old 06 January 2012, 17:39   #15
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: snagglepuss
Make: Shetland
Length: 6m +
Engine: 90 hp Outboard
Join Date: Nov 2011
Posts: 562
you are still welcome to pop round for a coffee!
__________________
clydeoutboards is offline   Reply With Quote
Old 06 June 2012, 02:58   #16
Member
 
lightning's Avatar
 
Country: UK - England
Town: Marple
Make: Zodiac
Length: under 3m
Engine: Tohatsu 9.8
Join Date: Jun 2009
Posts: 601
Just thought I'd update this thread. I've used the Tohatsu 9.8 on my SIB and can report that it works fine at low speeds on the canal. We went out for about 3 hours at speeds of 2-4mph which is pretty low RPM.
The engine did not complain at all, and the noise it makes is just a fairly quiet humming, in my opinion no worse than my previous engine, a Mariner 6hp 4-stroke.
The Tohatsu has a rubber damped/mounted power head so vibrations are not transmitted to the tiller which is better than the Mariner, which made my hand go to sleep after a couple of hours.
At higher RPM the engine just hums and I imagine it will be easier on the ears when planing as well, not tested this on the canal of course.
I'm guessing that this is due to the Tohatsu being a twin cylinder engine as much as anything.
Oh and the fuel quantity in the tank hardly seemed to drop at all with 3 hours trolling.
__________________
lightning is offline   Reply With Quote
Old 07 June 2012, 17:32   #17
Member
 
Country: UK - England
Town: London
Boat name: Yellow Peril
Make: Ribcraft
Length: 5m +
Engine: Yamaha 100 (2T)
Join Date: May 2006
Posts: 82
Quote:
Originally Posted by lightning View Post
Just thought I'd update this thread. I've used the Tohatsu 9.8 on my SIB and can report that it works fine at low speeds on the canal. We went out for about 3 hours at speeds of 2-4mph which is pretty low RPM.
I have used my Yamaha 8hp 2T twin on a Zodiac. Nearly always WOT after warm-up.

It's now powering a displacement boat with a finer pitch prop. Running 10-20% power. Am thinking about changing spark plugs to a different temperature range, to avoid oiling the plugs. Might be helpful if the oiling becomes an issue for you.
__________________
hobnob is offline   Reply With Quote
Old 08 June 2012, 02:51   #18
Member
 
lightning's Avatar
 
Country: UK - England
Town: Marple
Make: Zodiac
Length: under 3m
Engine: Tohatsu 9.8
Join Date: Jun 2009
Posts: 601
I'll see how it goes, currently running in on 25/1 premix so it smokes a bit, should be better when I change to 50/1
__________________
lightning is offline   Reply With Quote
Old 08 September 2014, 17:16   #19
Member
 
lightning's Avatar
 
Country: UK - England
Town: Marple
Make: Zodiac
Length: under 3m
Engine: Tohatsu 9.8
Join Date: Jun 2009
Posts: 601
Two years down the line and still using the Tohatsu 9.8, which is currently fitted to my friend's Honwave SIB.

The boat is kept in Anglesey, at my friend's caravan site.

It is hard to fault this engine, in its' class. Just a shame it can no longer easily be bought new in the UK.

It started second time this year after being sat in the garage untouched all winter. I'd recommend this engine for any small boat where you have to manhandle the engine on and off.
__________________
lightning is offline   Reply With Quote
Old 10 September 2014, 03:25   #20
Spammer
 
Country: Canada
Town: Southern Ontario
Boat name: -Unknown-
Make: SeaMax
Length: 4m +
Engine: Merc/Minn Kota
Join Date: Mar 2012
Posts: 216
Tohatso makes all smaller engines for Merc. I'm using a merc (2004) 9.9hp and it pushes my 14' Seamax beautifully. Have had two other adults onboard and it still reaches plane easily. I keep my type 31 Battery, 55 lb thrust electric and 6 gallon fuel tank at the front to balance weight making the boat jump on plain fast as well as keeping the bow down.
__________________

__________________
Nightfisher is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




All times are GMT -5. The time now is 04:55.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.