Troybilt Super Bronco 54 FAB Fuel Leak

[Denna]

Regarding a Troybilt model 13AQA2KA011 with a Kohler KT-740 engine.

1) While mowing, a fuel leak occurred. The fuel is squirting into the air cleaner base. See attachments.

2) Also, the throttle lever is difficult to move to the start position.

Any idea as to where to start troubleshooting ?

 

[ILENGINE]

Look on the bottom side of that air cleaner base and determine were the line connects to. I suspect that it connects to the top of the fuel tank, and the tank has been overfilled and fuel is expanding and pushing fuel up the tank vent vapor line into the air cleaner housing. If the line connects to the breather on the engine then check the engine oil because that would mean there is gas in the oil.

 

[StarTech]

Shouldn't the roll over valve be stopping it? I can understand if is sloshing up the vent line before the valve closes but even that should be prevented.

 

[ILENGINE]

Shouldn't the roll over valve be stopping it? I can understand if is sloshing up the vent line before the valve closes but even that should be prevented.

The filter neck is extended down into the tank to help prevent basically overfilling, but people will keep slowing adding fuel to the tank until no space is left and then put the sealed cap on and it will push the fuel up the vent hose in combination with the slight vacuum created on the vent tube by the running engine. Lincoln welders a few years back had issues with people doing that with the Kohler engine equipped units, and it was causing hydrolock while running.

 

[Denna]

Look on the bottom side of that air cleaner base and determine were the line connects to. I suspect that it connects to the top of the fuel tank, and the tank has been overfilled and fuel is expanding and pushing fuel up the tank vent vapor line into the air cleaner housing. If the line connects to the breather on the engine then check the engine oil because that would mean there is gas in the oil.

The mower had been running for a few hours, so the fuel leak smell was noticed around half a tank.

If any amount of fuel is in the fuel tank (e.g. 1/2 inch), the fuel is spurted into the air cleaner base.

Looking underneath the air cleaner base, there is a 1/2" breather hose about 9" long and it routes at a 90 degree angle into the engine chassis. No fuel is leaking from this hose.

See page 30.

https://resources.kohler.com/power/kohler/enginesUS/pdf/32_690_03_EN.pdf

There is a 3/8" hose that is connected to the top of the fuel tank and the other end is hanging loose on the driver right side of the engine. I can't see where this hose would connect to the engine.