Would You Buy Another Tohatsu??

[a64pilot]

Originally Posted by hlev00

Someone pointed to the fact that Tohatsu now have EFI at the 9.9+ HP range. That seems to be a game changer for that range.

Suzuki has had a fuel injected 9.9 -20 HP since at least 2014, when I bought my 20.
But here’s the thing on both the Suzuki and apparently the new Tohatsu’s the 9.9 thru 20 HP are all the same motor, so the Tohatsu 9.9 weighs 95 lbs, the Suzuki 99 lbs.
The 20 HP’s weigh exactly the same, I don’t know about you, but a 100 lbs for a 10 HP motor is way over the top, light for a 20 though.

[Ike]

MY Suzuki 9.9 with electric start, 20 inch shaft, and high thrust gearbox and prop, weighs 98 lbs. This engine comes in four or five (lost count) models from a plain no extras 15 inch with pull start model, to a model with electric start and remote controls and steering. They all vary in weight. Yes that is heavy for a 9.9, but not for a 20 which the engine is based on, They have different computer profiles and setups. But basically it is the same machine.

But that has been standard practice in the outboard biz for a long time. In 1985 I visited the Mercury Marine operation (their testing facility) in Oshkosh WI. On one rack they had about 10 engines, they all looked exactly the same (they didn't have cowlings on them so you could actually see the engine. ) The engineer from Merc said this first one is 130 HP. They are all a different horsepower, and the one down on the far end is over 200, but they are all based on the same block.

[cottonsail]

Originally Posted by Ken Pole

Gave up on conventional outboards; Lehr propane altenative a treat in terms of fuel availability and consumption as well as storage.

Research on Lehr was not good.

[Chotu]

Originally Posted by hlev00

I assume this is a 4-stroke. Is the engine tilted up, or down in the normal position for operation, when on the davits? If it is tilted up and there is much movement on the davits underway, you are shaking the oil around and it is getting into the cylinder. We have a similar problem if we leave it on the dinghy, tilted up, while towing if there are many waves, so we don't. If we tow with the engine on it is only on calm days or off the wind with relative small (< 2ft) seas. Other than that we put it on the pushpit bracket.


If tilted up, be sure you rotate around with the tiller down. Even if you leave it down, there may be enough movement to slosh the oil around.

I leave it down in the normal operating position. It’s at an angle opposite of the tilt up setting. Tipped toward the rear/stern part of the outboard because the entire dinghy is tilted back like that. It is kept bow-up so the rain can drain out of the self bailing plug aft.

This gets oil into the cylinder every single time I’m putting the dinghy on the davits, which is actually every day. I don’t leave it down in the water.

I’d this harming the new engine?

Any other suggestions aside from removing the outboard every time I use it?

[Ox76]

I'm not a sailor but I'm a lifelong mechanical type person. To keep oil from getting past your piston rings while the outboard is on your dingy which is nose high for drainage purposes, the short answer is to do whatever you have to do to keep that engine straight and level. You won't have any more problems with oil in the combustion chamber after you do this. It'll start easier too, because oil doesn't compress and causes harder starting and/or fuel ignition problems.

Edit: For what it's worth, this is my first post in the 5 years since I've been registered here and a couple years before that!

[motion30]

It sounds like you have possibly blown a head gasket when you overheated that motor

[a64pilot]

Originally Posted by Chotu

I leave it down in the normal operating position. It’s at an angle opposite of the tilt up setting. Tipped toward the rear/stern part of the outboard because the entire dinghy is tilted back like that. It is kept bow-up so the rain can drain out of the self bailing plug aft.

This gets oil into the cylinder every single time I’m putting the dinghy on the davits, which is actually every day. I don’t leave it down in the water.

I’d this harming the new engine?

Any other suggestions aside from removing the outboard every time I use it?

My Suzuki will smoke when started if it was tipped, and sometimes there will be a sheen on the water too, but I think it’s fuel, not oil.
Oil smoke doesn’t clear up real fast, and this does. If it’s oil it’s less than a drop because it doesn’t take much oil to make a LOT of smoke. Plus I have no oil consumption.
Been doing it for six years, so I don’t think it harms anything.

[Icarus]

Originally Posted by Chotu

My 5 year old Tohatsu MFs 8 outboard has been just awful to me.

It was overheating because the thermostat went. Finally got that squared away and running well, now a month later, there is water in the oil!!

Today, I couldn’t get the pull start going. Seemed seized.

I rotated it by turning the prop by hand and then it started being able to be pulled by the pull start.

Pulled it hundreds of times since it sometimes requires that after sitting in the davits.

Some hydrocarbon droplets were seen in the water, but I figured it might have been a carb overflow from tipping the motor.

After getting too tired from pulling and having it only attempt to start a couple times out of the hundred or so pulls, I decided to check the oil.

The oil spurted out the dipstick hole and overflowed. It was not normal color. Not super milky but a bit milky. Like caramel.

I had been running with no thermostat waiting for one to come in. I have it now and it’s on my to do list. But, now water is getting into the oil.

What the heck is going on with this thing???

Should I cut my losses and get a new outboard? Get it professionally repaired?

Would you buy another tohatsu after this?

Apart from some gasket issues your motor seems to have ignition problems.
Why not get the ignition parts and the integrity of the ob tested?
Sometimes too much 2stroke oil in the petrol mix can give starting dramas.
Get it looked at by an ob mechanic.

[Icarus]

Originally Posted by Dockhead

I have the 3.5 (branded Mercury). It stopped running due to deteriorated gasohol fuel. But I'm not sure why these would be more vulnerable to that than any other small 4 stroke. I have switched to naphtha based "engineered" fuel and so far no
It's a cheaply made engine but it was cheap to buy. I haven't yet concluded that it's not a decent engine, but we'll see.

These small engines are very basic, they tend to be fussy about the correct fuel/oil mix. 50:1
I learned to keep the carburettor clean and empty when the ob is stored for longer periods.

[Lake-Effect]

Originally Posted by Icarus

These small engines are very basic, they tend to be fussy about the correct fuel/oil mix. 50:1
I learned to keep the carburettor clean and empty when the ob is stored for longer periods.

The OP is discussing 4-stroke engines.

But yes emptying the carb before storage is a good idea for both types.

[Chotu]

The 2020 9.9 EFI has more tilt positions than my 5 year old 8hp did. I was able to tilt it up about 10-20 degrees to match the tilt of the dinghy while on the davits. No more oil where it shouldn't be going and starts second pull without the cloud of smoke.

The EFI starts in 2 pulls instead of one because the first pull is needed to energize the EFI system.

Looks like I have a working setup now.

[s/v Jedi]

Originally Posted by Chotu

The 2020 9.9 EFI has more tilt positions than my 5 year old 8hp did. I was able to tilt it up about 10-20 degrees to match the tilt of the dinghy while on the davits. No more oil where it shouldn't be going and starts second pull without the cloud of smoke.

The EFI starts in 2 pulls instead of one because the first pull is needed to energize the EFI system.

Looks like I have a working setup now.

Hmmm... I think it takes two pulls on my 20hp efi as well... even though I have a battery hooked up?

Amazing how light the pull is with automatic decompression. My old motor was a Yamaha 25hp Enduro which is a beast to pull... when it was new I could barely do it. I am very happy with the new motor and it is a perfect match with the Highfield Classic 340.

[a64pilot]

The Suzuki starts first pull almost every time, that’s what amazed me, that it could do that. It does so without any capacitor holding current too, or since it will do that after sitting for months I assume that anyway.
There can’t be any “booting” of the system, so no software. I say can’t because fuel injection and ignition is pretty much instaneous.

That can be done, the GE H-80 turbine is electronically controlled now, limiting torque, TGT and N1 speed and other limits, without any software, they did that because software is notoriously hard to certify.
So if you can electronically control a turbine without software, I’m sure you can an outboard.

[s/v Jedi]

I found this in the manual:

[a64pilot]

This states the Suzuki and the Mercury require two pulls, but mine starts first pull?
Either they are guessing, or maybe I’m pulling out more rope?

Interesting, do any others Suzuki start on the first pull?