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Exhaust idle relief system

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Waynebreau

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Hoping someone knows something about this problem I am having with my 2014 Mercury 60 hp Bigfoot. Water bubbles out from the lower exhaust and is worse while idling. Someone told me to insert a thin wire into the top exhaust port and try to unblock the line. Any suggestions or advice before I try this?
 
How about some history. There are two systems involved in non moving engine operation:
1. One is the exhaust that exits the prop.
2. The "Idle Relief" which ports are just below the rear of the clamshells at the top of the mid section which let exhaust gasses exit without having to overcome water pressure (against the prop outlet) as an aid in starting the engine.

When you go to start and run the engine, the idle Relief ports remove the back pressure from the combustion chamber so that the engine will start. Once the engine starts, the volume of exhaust gasses increases and they exit not only the Idle Relief ports, but the regular engine outlet which is bubbles out through the prop hub that rise to the surface.

Is this something that never existed before or has it possibly been happening since you had the engine and just now noticed it?
 
Texasmark said:
How about some history. There are two systems involved in non moving engine operation:
1. One is the exhaust that exits the prop.
2. The "Idle Relief" which ports are just below the rear of the clamshells at the top of the mid section which let exhaust gasses exit without having to overcome water pressure (against the prop outlet) as an aid in starting the engine.

When you go to start and run the engine, the idle Relief ports remove the back pressure from the combustion chamber so that the engine will start. Once the engine starts, the volume of exhaust gasses increases and they exit not only the Idle Relief ports, but the regular engine outlet which is bubbles out through the prop hub that rise to the surface.

Is this something that never existed before or has it possibly been happening since you had the engine and just now noticed it?
Click to expand...
 
Much appreciate that information as I am fairly new to boating and certainly not familiar with the workings of an outboard.
The boat was purchased in 2014, new and has a 60 hp Mercury Bigfoot. I had no issues whatsoever until last week when I noticed bubbling from the lower exhaust on both sides. Someone told me to insert a stiff wire into the upper idle relief port to try to clear any material that may be blocking it from releasing gas. Your thoughts would be most appreciated.
 
Waynebreau said:
Much appreciate that information as I am fairly new to boating and certainly not familiar with the workings of an outboard.
The boat was purchased in 2014, new and has a 60 hp Mercury Bigfoot. I had no issues whatsoever until last week when I noticed bubbling from the lower exhaust on both sides. Someone told me to insert a stiff wire into the upper idle relief port to try to clear any material that may be blocking it from releasing gas. Your thoughts would be most appreciated.
Click to expand...
Maybe the bubbling was always there and you didn't notice it.....those things happen.....to me anyway...learn something every day on my farm.
 
It is definitely happening when I first start the motor at the dock, and while it idles there, and when I am slowing down to dock the boat.
 
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