Good afternoon every one, I'm a new member for this forum, from Malaysia. Happy to meet you all, friends. I'm utilizing Outboard Mercury 115, 4 stroke

[Mohamad Nor Awang]

Good afternoon every one, I'm a new member for this forum, from Malaysia. Happy to meet you all, friends. I'm utilizing Outboard Mercury 115, 4 stroke. Recently while navigating, my keep jerking. I suspect air in the fuel piping, between engine and fuel tank. Each time while this occured, I observed rubber fuel pump deflate. The fuel filter input and output pipe located higher or same level as fuel filter itself. I also observed that air in the upper part of fuel filter. Could this possiblity for the occurence ??

 

[Papa-t]

Welcome to the forum

 

[KJM]

Good afternoon every one, I'm a new member for this forum, from Malaysia. Happy to meet you all, friends. I'm utilizing Outboard Mercury 115, 4 stroke. Recently while navigating, my keep jerking. I suspect air in the fuel piping, between engine and fuel tank. Each time while this occured, I observed rubber fuel pump deflate. The fuel filter input and output pipe located higher or same level as fuel filter itself. I also observed that air in the upper part of fuel filter. Could this possiblity for the occurence ??

Welcome! Are you sure the engine is not sucking air into the lines from a improper or loose connection? Is it a built in or portable tank?

 

[Mohamad Nor Awang]

Welcome! Are you sure the engine is not sucking air into the lines from a improper or loose connection? Is it a built in or portable tank?

Portable fuel tank sir. Original engine came together with small tank, I had replaced with 160 litre tank for long distance moving. A connector at the portable tank were two outlet lines, so I blockked one line, only utilised one. The connector outlet was fitted properly by using metal clip.

 

[KJM]

Is it possible that the line is connected backward? I think those primer bulbs are only flow one way.

 

[KJM]

You also might get more replies if you post your question in the Mercury Outboard section instead of here.

 

[Mohamad Nor Awang]

You also might get more replies if you post your question in the Mercury Outboard section instead of here.

Thank you sir.

 

[Dave1027]

The primer bulb deflating would indicate a restriction in the fuel line from bulb to tank or the tank vent is plugged.

 

[Mohamad Nor Awang]

Thank you sir, I will inspect the parts you mention throughly, rectify if any defected.

 

[QBhoy]

Hi. If this is in anyway a modern 115 4 stroke..you shouldn’t have a primer bulb at all. I’d also suggest that if you do, it may be the wrong way around. I’d get rid of it altogether. I don’t have one fitted to my 115

 

[Mohamad Nor Awang]

Hi. If this is in anyway a modern 115 4 stroke..you shouldn’t have a primer bulb at all. I’d also suggest that if you do, it may be the wrong way around. I’d get rid of it altogether. I don’t have one fitted to my 115

Sir, you means the rubber pump, shape like rugby ball to pumping the fuel from the tank to the engine?

 

[Mohamad Nor Awang]

Sir, you means the rubber pump, shape like rugby ball to pumping the fuel from the tank to the engine?

I installed one, should this things caused the problem??

 

[QBhoy]

I installed one, should this things caused the problem??

You don’t need one on that engine. If it is fitted in the wrong direction, it could certainly be the issue

 

[Mohamad Nor Awang]

Thank you very much sir for you advice, I'll disamble the thing. Hopefully problem could be rectified.

 

[QBhoy]

Thank you very much sir for you advice, I'll disamble the thing. Hopefully problem could be rectified.

Just have a look at the arrow on the primer bulb. See what way it’s facing. They should only go one way. Don’t need it on this engine, as said, but may be handy occasionally for priming any water separator filter you might have…