4 cycle outboard maintenance

[tweitz]

As a long time sailor, I generally try to avoid dealing with engines whenever possible. However, I need to think about my dinghy engine, a 4 cycle Tohatsu. In the past it has run into problems which required cleaning the carburetor at some expense when done by the yard. I would like to do whatever needs to be done myself, and was wondering if those experienced in the matter could give me a checklist as to what needs to be done and how.

[LakeSuperiorGeezer]

You need a carburetor kit. Use a search engine and search for Tohatsu carburetor kit. You will have to narrow it down to the engine model. Hopefully there will be instructions with the kit. If not probably can find something online. You will need written instructions. You cannot guess at the float level setting. You may have to buy the shop manual, but if you are interested in doing your own work, you should get one anyway for any other issues. When was the last time you changed the water pump impeller and the gearbox oil for instance?

[Liquorice]

Did you have trouble with the carb after laying up the engine for the winter?
It's not normal to pull carbs apart unless the engine is getting old.

If it's a newer engine, and the carb got gummed up during a winter layup, you need to run the engine dry of fuel before putting it to bed for the winter.
Run the engine, turn off the fuel or disconnect the fuel line and let the engine burn up all the fuel in the carb. It will sputter to a stop.
That way there will be no fuel left in the carb and float chamber that can evaporate and gum up the tiny orifices (holes) that meter the fuel.

I've just had a look at the owners manual for the 4,5 & 6 hp Tohatsu, it says to strip the carb every 100 hrs - nobody does that!

sam :-)

[dabnis]

Tweitz,
Suggest you drain the carb instead of "running it dry", which may leave
a small amount of fuel in the bowl which can evaporate, leaving deposits
which can then be sucked up into the jets the next time you use it.
More here: http://www.sailnet.com/forums/gear-m...tml#post689419

Dabnis

[tweitz]

Thanks all, I have had the yard do the annual maintenance and it just seems to me to be way too expensive. I do run the engine dry each year, but it seems to be far more sensitive than my old 2 cycles, which did nothing but run.

[southshoreS24]

get the repair manual, run dry after each use, drain bulb if sitting for more than a few days. depending on what maint has been done, things to look into are the thermostat, impeller, plugs, lower unit oil, and engine oil. all normal maint and will be covered in the repair manual.

[PaulfromNWOnt]

Before I put a wrench to a still running engine, the first thing I try is adding a couple glugs of seafoam to the gas. I've run that stuff through my snowmachine, motorbike, and chainsaws with great results. If you are reluctant to try this, you can try the other method I used previously which was to run a couple of glugs of fuel injector cleaner in with every tank. Safe on aluminum parts, and kept things all nice and spiffy.