A question for outboard pros.

Bought a 2020 Tohatsu Sailpro 6hp. Went for a shakedown cruise and things were decent. We motored around our bay at various speeds with no problems. As we were returning, maybe 30 meters from our slip, the motor started to chuff at low rpms and just died. I tried to goose it with some throttle but there was no response, then it stalled. I'm wondering if there was crap in the fuel line that would cause this? When we got it to our slip, I noticed the primer bulb was a little soft, so I primed it again and things seemed normal again. Anynthoughts or suggestions would be appreciated. Cheers!

Posted Jul 4, 2022, 9:46 PM UTC

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Beechcraft77•

Non-Vented fuel cap? I sail on a tank that needs to be loosened a quarter turn so it doesn’t create suction that results in the exact same sequence of events you describe

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Alecto7374OP•

That could be a real possibility, never even thought to look. Thanks for the idea.

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Alecto7374OP•

One other tidbit I forgot to mention..when in either forward or reverse gear in low rpms, and I go to neutral, she revs super high so I need to back off the throttle so I don't damage the tranny. Doubt it's related to the other issue but wondered if there's a way to lower neutral idle speed

2
FunClothes•

There's a throttle tension adjustment thumbwheel knob on the underside of the throttle handle to hold the throttle setting where you set it - which is what you normally want when it's being used as an auxiliary - so you do need turn the throttle to back it down to minimum and wait for the boat to slow and revs to drop before you shift gear.

If that's not the issue then there's an idle speed adjust screw where the throttle cable turns the shaft for the butterfly in the carby. If it's not idling too fast in gear yet way too fast in neutral at minimum throttle setting, then combined with the other issues you've had, IMO you should probably get it checked and serviced by a tohatsu dealership.

3
sailingtroy•

I had this caused by a missing hose-clamp on my fuel line. Air was getting sucked in. Sometimes the fitting on the engine just sucks (air) literally. It may be that your idle screw has just backed off and turning it in slightly will fix your problem.

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FunClothes•

I think that sounds reasonably likely. If the vent was fully closed then the squeeze bulb would normally be more than "a little soft" but sucked in on itself before the engine starved for fuel. Even the sides of the plastic tote tanks get sucked in.

OP should also check for water in the bottom of the tank, a good dunking with cold water if the tank is warm and the vent open, then water gets sucked in.

There's a fuel filter - usually transparent or translucent plastic under the cover between the fuel fitting and carby. If the motor is run in a tank with the cover off, then you should be able to see if air bubbles are being drawn through.

1
SailingSpark•

I can remember motorsailing with my parents on a calm day decades ago. People looked shocked when I pointed out the half collapsed plastic tank.

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FunClothes•

It's an easy mistake that everybody has probably made at least once.

I looked at someone's setup when they had an issue with their outboard dying much as the OP describes, problem was a small split in the hose between the bulb and the tank. Possibly split from having the fuel locker hatch closed hard on it. He "thought he could smell fuel" earlier but assumed it was just a little bit coming from the vent - so closed it. It was a warm day, vapour pressure in the tank had been squirting fuel everywhere.

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brdynumnum•

I have the same motor. The low speed jets are very small and prone to plugging up, they're strong runners but notoriously sensitive.

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Alecto7374OP•

So, as previous posters replied, I wonder what mucking with the knob on the tiller would do?

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reflUX_cAtalystCatalina 22, J/80, Farr30•

Make sure the vent on the cap is open, otherwise you'll pull a vacuum and fuel won't flow.

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