Recommissioning procedure for 2-stroke outboard motor ?

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Boo2

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Hi,

I've got a Tohatsu 3.5 hp 2-stroke outboard that has been standing for 4 years and wondered what I need to do to ensure reliable operation when I recommission it ? Obviously I will change the plug and discard / renew the fuel but it may have been left with fuel/oil in the carbs etc so does anyone have a complete list of what is required to look at / renew ?

Many thanks,

Boo2
 
Boo2 said:
Hi,

I've got a Tohatsu 3.5 hp 2-stroke outboard that has been standing for 4 years and wondered what I need to do to ensure reliable operation when I recommission it ? Obviously I will change the plug and discard / renew the fuel but it may have been left with fuel/oil in the carbs etc so does anyone have a complete list of what is required to look at / renew ?

Many thanks,

Boo2
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There is a guide on the iboats forums but it is mainly concerned with larger outboards. You can cherry pick the relevant parts though.

http://forums.iboats.com/forum/engi...231-awakening-a-sleeping-outboard-by-boatbuoy

water pump impeller would be near the top of my list, together with checking the gear oil and doing all the other normal routine service items.
 
Tam Lin said:
Just put some new petrol in it, if it starts, use it. It will be fine!
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That was my first thought too. And if it doesn't start, take the carb off and give it a clean.

But Vic's suggestion of checking the impeller is a good one. They're often neglected. And gear oil while you're down there wouldn't hurt.

Pete
 
I left my Evinrude 4hp for 4 years....got it out the shed...started 3rd pull. Didn't even get new fuel....been using it all season not missed a bit... :-)

Just wondering if I should give it a treat and rinse with fresh water....or maybe some vinegar even now it's home in garage again.

Guess it depends on how critical it is...mine is tender use and should it pack up I can row.
 
Most engines like this have a drain screw under the carb float bowl; worth undoing, but they can require unbolting the carburettor for access.

Wheelie bins make good test tanks...
 
I'm
prv said:
That was my first thought too. And if it doesn't start, take the carb off and give it a clean.

But Vic's suggestion of checking the impeller is a good one. They're often neglected. And gear oil while you're down there wouldn't hurt.


Actually, thinking about it a bit, checking the gear oil is a good idea. I bought an engine off eBay once, saw it running, thought I would give it the once over when I got home - no oil in the gearbox! Filled it and congratulated myself for having the forethought then put it away. A few days later I went to get it out and discovered why the gearbox had been empty, the oil had leaked all over the floor! New seals sorted it.
Pete
Click to expand...
 
Boo2 said:
I've got a Tohatsu 3.5 hp 2-stroke outboard that has been standing for 4 years and wondered what I need to do to ensure reliable operation when I recommission it ?
Click to expand...

Open the fuel tap. If petroil piddles out, unstick the carburettor float. If it doesn't, just start it.
 
Shirley not the best idea with fuel that old ?

I was told by the chap in the motor section of our garden centre that a large part of his annual work is in the Spring when people try using mowers etc with last year's mix - and that modern unleaded fuel is much more prone to gumming up jets etc.

He could see he wasn't getting any money out of me so I don't imagine he made it up, my top notch mechanic chum ( also A22 owner :) ) feels the same.
 
Seajet said:
I was told by the chap in the motor section of our garden centre that a large part of his annual work is in the Spring when people try using mowers etc with last year's mix - and that modern unleaded fuel is much more prone to gumming up jets etc.
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That can certainly happen if you leave the float chamber full so that the petrol evaporates and the oil remains to gum things up. I'm not convinced that much can go wrong with petrol or oil in a sealed tank, though. How many millions of years was the stuff underground?
 
The way I've heard it, from mower bloke and mechanic chum, is that unleaded petrol alone can go gummy, even without 2-stroke oil - but of course old mixed fuel is more dodgy.

Being half Scottish myself I always use the old fuel in my ( non catalytic ) car when there's a decent amount in the tank to mix it all up.
 
Seajet said:
Shirley not the best idea with fuel that old ?

I was told by the chap in the motor section of our garden centre that a large part of his annual work is in the Spring when people try using mowers etc with last year's mix - and that modern unleaded fuel is much more prone to gumming up jets etc.

He could see he wasn't getting any money out of me so I don't imagine he made it up, my top notch mechanic chum ( also A22 owner :) ) feels the same.
Click to expand...

I only use the most expensive (£20 a litre, as used in super high performance kart) 2 stroke oil....maybe that's the difference.
 
New fuel.

If it does not start check plug. If dry clean carb. [ NB if stored with fuel in carb and tank expect to do this this at least twice. ]

When it starts check to see water is flowing from pee hole. If not rod it out with some wire.

If no flow from pee hole tilt the running engine and see if water is coming out the exhaust. Before attacking lower unit be really sure you need to do this. Getting it apart can be a b***** seized bolts etc. Getting it back together is really fiddly.
 
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In addition to all that I usually pull the plug out give it a clean and pour a little bit of 2 stroke oil down the bore and give it a few pulls before putting the plug back in, just gets it all lubricated as it may have gone completely dry and thats when wear happens, you get a nice puff of smoke when she fires too
 
I had the 2.5hp version of that outboard and recommissioning was fairly straight forward. Impellor check, gear box oil, new spark plug, clean carb new fuel.

Also worth checking the float height in the carb. Mine was out by a bit leading to flooding.
 
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