Tohatsu 3.5 Gas Tank

Sea Rider

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Sep 20, 2008
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Was wondering if it's safe to turn up side down a new 3.5 engine to remove gasoline mix that has stayed in for a long period, which won't run the engine as expected. Will you have oil passing from tail to exhaust ?

Happy Boating
 

pvanv

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Apr 20, 2008
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Re: Tohatsu 3.5 Gas Tank

If you invert a Tohatsu/Nissan (or any other brand) 4-stroke OB, you will spill crankcase oil where you don't want it. No problem with a 2-stroke, as there isn't any crankcase oil.

LU lube will stay in the LU for either a 2- or 4- stroke, as it is sealed.

It's only a couple of 6mm bolts to pull the tank off to flush it, BTW. Of course on the M3.5 2-stroke, there are a bunch of screws to remove to get the cowling off to access the fuel tank.
 

Sea Rider

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Re: Tohatsu 3.5 Gas Tank

If you invert a Tohatsu/Nissan (or any other brand) 4-stroke OB, you will spill crankcase oil where you don't want it. No problem with a 2-stroke, as there isn't any crankcase oil.

LU lube will stay in the LU for either a 2- or 4- stroke, as it is sealed.

It's only a couple of 6mm bolts to pull the tank off to flush it, BTW. Of course on the M3.5 2-stroke, there are a bunch of screws to remove to get the cowling off to access the fuel tank.

Hola Paul,

Yes, that was the issue of removing 6 mm bolts to remove lateral cowling, too complicated for J-24 boaters to do it rather often, better do a quick 2T engine inversion and that's it. Thanks.

Happy Boating
 

Mark SF

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Jul 15, 2010
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Re: Tohatsu 3.5 Gas Tank

How I did it : remove the pipe from the output of the cut-off valve, and then place the output of the valve over a receptacle - open the valve and the fuel pours out. Let it all drain out then add a little more gas to the tank to flush it.
 

TOHATSU GURU

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Jul 22, 2004
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Re: Tohatsu 3.5 Gas Tank

How I did it : remove the pipe from the output of the cut-off valve, and then place the output of the valve over a receptacle - open the valve and the fuel pours out. Let it all drain out then add a little more gas to the tank to flush it.

Simplicity itself and that is the correct way to do it:)
 

Sea Rider

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Re: Tohatsu 3.5 Gas Tank

A valid answer, but will have my doubts if crew members will do the job, surely will be delegated to the boat's unskilled seafarer who will end loosing screws, breaking the pipe, fuel ****: unwanted trouble. If you have no experience whatsoever with 3.5 B2 engine removing gas procedures, better go simple and flip the small beast, anyway after complete removal of old gas, can add a small new amout and shake to rinse tank, flip it one more time :D

Don't have a 3.5 B2 at hand, but to perform that procedure, must you remove complete lateral cowling to gain access to gas **** hose ?

Happy Boating
 

TOHATSU GURU

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Re: Tohatsu 3.5 Gas Tank

Unless your a magician like me, yes....Actually anyone can do it from underneath if they are careful and don't mind scraped fingers. Sometimes the screws weld and it would take longer than the typical 30 seconds to remove it, that's when it's time for Bloody Fingers 101.
 

Sea Rider

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Re: Tohatsu 3.5 Gas Tank

Unless your a magician like me, yes....Actually anyone can do it from underneath if they are careful and don't mind scraped fingers. Sometimes the screws weld and it would take longer than the typical 30 seconds to remove it, that's when it's time for Bloody Fingers 101.

TG, next time a maintenance is needed on these babies will take a look at your procedure, but frankly, would preffer a bloody mary than bloody fingers!!!

Happy Boating
 
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