thinking of buying an 5-6 hp Tohatsu

So I am thinking of buying an Tohatsu outboard and I have 2 choices:

2 stroke 5 hp
4 stroke 5 hp

so which one would you take? The 4s is 100 euros more expensive but at using 2l of fuel per hour less and 1l costing 1euro in 50 hours (2 years in my case) it would repay the difference but cause I have like 20-25 hours a year fuel isnt a big issue

My main question is about reliability and maintenance and over all performance and which one is more quieter and so more pleasant for driving

and cause as I saw on the tohatsu website the only difference between 5 and 6hp is in the rpm and cause the rpm is controlled in this case by the ignition could it be changed so that i get the 1000 more rpm on the 5hp so it will have more power?

I would go for the 2 stroke

pro's of the 2-stroke is lighter weight and easier to maintain. con's are less fuel economy, have to pre-mix oil/gas, more smoke (due to premix) and less environmentally friendly.

Quietness and smoothness at this h.p. range (1 cylinder) is about the same. As you get bigger h.p. (2, 3 4 cylinders) the 4-stroke is smoother. But a single cylinder is going to be about the same either way.

So it really just depends on what's important. If you're going to be lifting/carrying the motor a lot, less weight is important and if you'll be traveling to a lot of underdeveloped countries, then a 2-stroke will be easier to get service (just about anyone knows how to work on a single cylinder 2-stroke)

But if you like better fuel economy, don't want to mess with pre-mixing oil/gas and don't like the smell of 2-stroke smoke, then 4-stroke is the way to go.

Oh and the 5hp & 6hp 4strokes are the same block. The additional hp is due to different carburetors. While you could buy a 6hp carb and put in in the 5hp, it's just a inexpensive to just buy a 6hp to start with.

Thanks guys

so I am probably going with the 2stroke cause if its cheaper,lighter and easier to maintain I will probably deal with the premixing and smell of the premix.

And any suggestions when I buy it on some useful things I should know?

I have a 5hp 4 stroke and it is the best small engine I have ever owned. Very quite and smooth. Burn no gas! I have it on a 10 foot inflatable and can use it all day on less then two gallons of gas. It only weighs 55lbs. Great engine. The two stroke is much louder and vibrates a lot more.

I say go with the 4 stroke . Ihave a tohatsu 4 hp 4stroke (bought new) and it runs good !!!!!! No mixing gas oil runs all day on less than 1gallon
has a crank case for oil so lubes better than a 2cycle and has lots of new invoations like single peice ingintor (no different parts for ingition under flywheel (i could go on)!!!!! If you get it in the box youll need to do the setup yourself (which is what you shoud do to learn the motor)
check both oil levels spark plug etc. When you go to start/choke motor for first time have it in a 5gal bucket of water and be ready with a screw driver to set the idle screw (is on top of carb with little spring0
once engine fires you push in choke and bring throttle grip up to half way position ( if engine reving to much (adjust the idle screw) thats the frist part hope it helps !!!!!!!!!oh one other thing get the 4hp motor the 5 and 6 are really exactly the same you will see no difference except price
wheter its mercury nissian or tahatsu(by the way yamaha has a big background in the invoations of these motors !!!!!!!!!!!

If you are looking at single cylinder motors you should consider -

with a 2 stroke every revolution is a powerstroke

with a 4 stroke every SECOND revolution is a powerstroke (exhausts every other)

so that poor little 4 stroke has to get the flywheel around twice before the cylinder fires again - which also makes it gutless compared to a 2 stroke of similar horsepower and displacement

while it may be "smooth" during it's first year or two of life many find that it starts to shake like a wet dog on a cold day unless you keep it perfectly tuned and end up on this site asking how to fix the idle on their "shaky" outboard

If the smallest twin cylinder 4 stroke is too big for your purposes, despite that huge burden of mixing a couple gallons of gas with oil, over the longer term most are much more pleased with the performance of a single cylinder 2 stroke

new here and bringing up an old post, but thanks "Galamb" and all the rest for some info on 2 stk. 5 hp. Lookin this weekend at one for sale. Circa 1993 2 stroke 5 hp. He's asking $800. I'll be honest I'm into cars/trucks not so much boat motors (this one for my porta-bote) what do you guys think of this price. Funds are CDN. Thanks Greg.

I wouldn't ask that much for an 18-y/o M5B on my used rack. Just sold a very clean 10 y/o M8B for $500 last week. With US/Can exchange at about par, I think you can do a bunch better.

my bad....yr.=2003

Assuming the model is M5B, since you cannot buy a new one (all the new ones will be 4-strokers), if you want it, and it's in good shape, OK... but the price still seems a bit high.

5B, ended up grabin it and I'm pretty excited. I'm aparently the third owner. Just looking at it it looks brand new and seemed to run very nicely. This is my first real boat motor not counting the elec. 55lbs thrust. Winter is fast aproching so wanted to do a little winter maintance. Today after work changed out lower unit gear oil (#90), ran tank dry until motor quit and there is just maybe 2-3 tea spoons of fuel left in the tank. Is this a good thing? Should I be removing the line where the filter is located and getting it all out? Speaking of fuel filter is that a replaceable part or just wipe off? Air filter-I see a cover and I removed the 2 philips screws holding it on, but no air filter??? Do these motors require one? I assume they do. Fogging-can anyone recomende one brand over another. It comes in an aresol can just like wd-40 can correct? When fogging just spray some in the spark plug hole and the carb? I reaize thats alot of questions, but I'm pretty anal when it comes to maintainance on anything and like to keep her running right. Last, but not least do they make a Haynes/Chiltons manual for these particular motor? Thanks very much Pidge. Paul it seems while serching around that they dont offer the built in gas tank on the 5's anymore. Just the 4hp and down right. What was the last year for the 2 stroke 5hp. with the built in tank on top of the motor?
EDIT: found these sources for repair manuals for anyone wondering http://www.nissanmarine.com/tech_talk/faqs.html#Q2

Would this one be the one I'm looking for? http://www.internetoutboards.com/partdetail.asp?id=579

Best to remove all fuel from everything for winter storage. When we winterize these in Buffalo, we use shop air to blow out all fuel lines and leave the tanks bone dry. We also drain the carbs using the drain screw. If too difficult to completely empty the tank, a couple of teaspoons in the tank would be OK, even though it will spoil and gel somewhat, since you will add a couple of liters of fresh, stabilized, 50:1 fuel in the spring. But beware it can clog the strainer at the fuel cock. The in-tank filter is part of the fuel cock. We do replace them when clogged. The filter for the remote tank, if so equipped, is a standard on-the-shelf in-line filter as used on the newer 4-strokes.

No air filter is used on any of the small outboards. That carb cover is the backfire spark arrestor, which reduces the chance of a puff of ignited fumes jumping out in the event of a backfire.

If you will only store the motor for a couple of months -- in a dry area -- fogging would be optional (though recommended) on a 2-stroke, since the fuel residue already contains 2% oil. If longer, or not dry, yes, aerosol fogging is a good idea. For tech info, including winterizing, see the Factory website at http://www.tohatsu.com/tech_info/index.html and click on the appropriate topic for a full rundown.

Don't bother with an aftermarket "doorstop" manual. Get the real Factory service manual from a dealer. Much better. Part # 003-21035-1 $42.47, available at any dealer, including me.

The M5 was available with either onboard or dual tank setup. The modern 4/5/6 is also capable of that arrangement, but in the 2010 models, only the MFS4 comes standard with integral tank -- one would add it to a 5 or 6 if desired.

If not known when the water pump was last serviced, installing a new WP kit would be a prudent thing to do.

Paul you've been a wealth of info my friend thank you very much. This 2 stroke thing is new to me. I've owned nissan trucks in the past and currently drive one today and take really good care with maintainance and I'm a firm beliver in it. I'll take your advice and use some compressed air to blow everything out concerning fuel lines. I've got the 5hp "in-tank" by the way. Your saying the fuel filter is part of the flow cock thingie, what I gather from what your sayin its one piece and both get replaced as one assembely? If so I'll grab one and replace. Good on the air filter. "Step 3" in the link you sent me for fogging, thanks. Will do on the water pump deal. I'll get one when fuel filter/fuel cock gets ordered. Thanks for the catolouge part #, gotta grab one of those as well. Paul thanks again for you assistance, I feel more confortable now. By the way I'm not to far from your location, just outside Toronto.

If you happen to be in Fort Erie or Buffalo some time, drop by the store; We're about 5 minutes from the Peace Bridge. We keep our boat in Wilson, and I compete in the LO300 sailing race every July, so am familiar with Port Credit and the GTA. Yes, the strainer is integral with the fuel cock. Also includes the stub of hose to couple it to the tank, and the clamp. They last a long time, but if they get really sludged up from gelling fuel, we change out the whole piece. 369703110M FUEL COCK (PLASTIC TANK) $25.18

Thanks Paul, but I currently dont have a passport nor have I ever had one. On the to-do list. Do you have a phone number for your store or a web link. If so I'll give you a shout about the manual and the nipple you thread into the motor to run a garden hose instead of dunking it into a drum. Thanks Greg.

You can always call the store at 716-877-8221, and we'll be happy to help you. Or our crummy web page, obersheimersails.com. This time of year, I'm only in the office a couple of days a week, typically MWF. We're as close as your mailbox or UPS truck, so no passport worries.

Still havent forgotten about you Paul. Having a few item shipped for the truck, after they arrive I'm calling.

tryed a long shot and called today, but you were out of office. I'll try again tomorrow. Thanks again Paul.

Thanks again Paul cant wait till summer and get this puppy in the water. One more question for the pro's. Should I, or is it nesacerry to leave the air bleeder on top of the gas cap open or closed while in storage? Its in the basement right now on the opposite side from the furnace and hot water tank. I opened it last week and there was definitly a vacume or pressure in the tank, I'm not sure which one and of course a hint of gas. Tanks empty per your instructions, but should I leave the bleeder open or closed? Thansk again Pidge.

Keep it closed whenever the tank isn't in use. There is a little residual gas in there that has expanded - that's a good thing - keep as much air out as possible (which will in turn keep moisture out). When you refill the tank in spring add a bit of fuel stabilizer (you don't have to go with the fancy marine stuff - "crappy tire" store brand is more than sufficient) - it will help prevent phase separation (water) in the tank caused by ethanol in the fuel, which attracts water.

Where are ya in Ontario?? I'm just north of Kingston...

Thanks Galamb makes sense. Brampton Ont.

PiDGE said:

Thanks again Paul cant wait till summer and get this puppy in the water. One more question for the pro's. Should I, or is it nesacerry to leave the air bleeder on top of the gas cap open or closed while in storage? Its in the basement right now on the opposite side from the furnace and hot water tank. I opened it last week and there was definitly a vacume or pressure in the tank, I'm not sure which one and of course a hint of gas. Tanks empty per your instructions, but should I leave the bleeder open or closed? Thansk again Pidge.

Click to expand...

Yes, if you're storing it with fuel in it, closed is best, as long as there won't be wide temperature swings that would pop the tank, or cause it to suck down and crack. However, it is better not to store the tank in the house at all. If you have a shed or garage -- some place that's OK for storing propane (LP) gas, that would be preferable. Gasoline fumes are heavier than air, and can settle on a basement floor (like coffee in a cup) until they find the pilot light of a furnace, boiler, or water heater.

Since these tanks only hold a whopping 3 gallons, better to dump the fuel out (run it in the snow blower, lawn mower, car, or whatever), leave the cap off for a few days so any residual evaporates completely out of the tank, and store the tank bone dry. Then there's no significant gas to make fumes at all, and whether the vent is open or closed is completely insignificant as far as fumes go -- though keeping the vent open will prevent the tank from puffing up or sucking down.

Right on thanks again guys. Theres just a touch, maybe 1/4 teaspoon mixed with gas stabilizer in one corner of the tank. Opened the bleeder again just now and there is still a little pressure in it. Paul I realize about the pilot light etc, thanks for looking out though.