At some point, the carburetor in your outboard motor may develop some issues.
One of it might be a mercury 9.9 4 stroke carburetor leakage problem.
When this occurs, it reduces the performance of the outboard motor and also leads to wastage of fuel.
Some of the reason why the carburetor of mercury 9.9 4 stroke leaks include stuck float, damaged bowl gasket, loose drain screw and incompatible carburetor rebuild components.
These issues can easily cause your carburetor to leak.
When you notice them, you have to fix them.
This will help increase the performance of your outboard motor and also avoid wastage of fuel.
Causes Of Mercury 9.9 4 Stroke Carburetor Leakage Issue
1) Stuck Float
The float in a carburetor controls the performance of the outboard motor in a lot of ways.
it dictates if the outboard motor will perform well or not.
One of the most important component of an outboard motor carburetor is the float needle.
With these components, the inflow and outflow of fuel into and out of the carburetor is controlled.
But when they develop a fault like getting stuck, the carburetor will be abnormal when the outboard motor is running.
This will lead to cases in which the carburetor overflows with fuel when the float needle is stuck in the open position.
Due to the overflow of fuel from the carburetor, the carburetor will leak and release fuel to the environment which is bad.
2) Damaged Bowl Gasket
Before the carburetor sends out fuel to the engine for combustion, it stores some volume of the fuel.
One of the reasons for this is to allow some debris to settle at the bottom before sending out fuel.
This part of the carburetor is the bowl gasket.
When the bowl gasket gets damaged due to cracks, leakage of fuel will occur.
3) Loose Bowl Gasket Screw
At the bottom of the bowl gasket, there is a screw.
This screw can be adjusted.
If the screw is not well tightened, it will become loose.
Due to this, fuel will leak out of the carburetor through the loose screw tread.
4) Loose Carburetor Drain Screw
Apart from having a bowl gasket screw at the bottom of the bowl gasket, there is another screw too.
This screw is the drain screw.
It plays a vital role when you want to perform a quick drain of fuel from the carburetor.
To achieve this, you just loosen the screw and then the fuel in the carburetor will flow out.
But trouble sets in if the screw is not well tightened.
This will cause a leakage from the carburetor when the carburetor drain screw is loosely tightened.
5) Incompatible Carburetor Rebuild Components
When a carburetor develops a fault like having a leakage, a lot of people prefare to rebuild it instead of buying a new one.
This is usually a cheaper alternative to keep your carburetor functional when it develops a fault.
But in making use of this method, there are always some flaws.
This is usually due to the compatibility of the rebuilding components with the damaged carburetor.
If the components do not fit well into the carburetor, then there will still be issues.
That is why you have to make sure that you buy your rebuilding kits from a supplier that has a positive review from buyers.
This will help save you the stress of an incompatibility issue and avoid leakage after rebuilding the faulty carburetor.
How To Fix Mercury 9.9 4 Stroke Carburetor Leaking Issue
1) Free Stuck Float Needle
When you discover that your carburetor is leaking, you have to make sure that you perform a troubleshooting.
This will help you determine what is the cause instead of making a guess work.
When you discover the cause, you have to fix it so that your outboard motor will perform well.
If after troubleshooting you discover that the cause of the leakage is a stuck float, you have to fix it.
To fix a stuck float, you have to open the carburetor and perform the fix.
If the carburetor is really damaged, then you have to consider getting a replacement.
2) Replace Damaged Bowl Gasket
When you notice a mercury 9.9 4 stroke carburetor leakage, you have to trace the leakage.
To do this, make sure that you wipe the carburetor with a clean clothe.
After that, observe where the leakage is originating from.
if it is from a crack through the bowl gasket, then you know that you need to replace the bowl gasket with a good one.
3) Tighten Loose Bowl Gasket Screw
After running a maintenance, some technicians can be careless.
One of the ways in which their carelessness shows up is when they fail to tighten the carburetor bowl gasket screw well.
Due to this, there will be leakage of fuel from the carburetor.
To solve this, you have to make sure that you tighten the bowl gasket screw well.
4) Tighten Loose Carburetor Drain Screw
At some point, you may want to drain the fuel in your carburetor.
It could be due to using a bad fuel or when its time to store your outboard motor for a long period of time.
In such a situation, it will be good to empty the carburetor.
To perform this, you need to loosen the carburetor drain screw.
This will allow the fuel in the carburetor to flow out.
But after that, you have to make sure that you tighten the drain screw well.
Without that, you will have a leakage from your carburetor.
To fix this, make sure that you tighten the drain screw well.
5) Use The Right Carburetor Rebuild Components
Carburetor rebuilding is always a very good decision.
It helps revive a bad carburetor back to functionality.
But during the rebuilding process, you have to make sure that you buy a good rebuilding part.
The part has to be durable and also match the dimensions of the faulty carburetor.
This will help avoid incompatibility issues.
If the parts are not compatible, you will still have issues.
It could be that the new float needle does not fit well thereby getting stuck.
To avoid scenarios like this, you have to make sure that you use a compatible rebuilding components.
What Happens When Mercury 9.9 Four Stroke Carburetor Leaks
1) Poor Performance
When you have an outboard carburetor that is leaking, the performance of your outboard motor will suffer.
A leaking carburetor will end up starving the combustion chamber of the volume of fuel it would have used for combustion.
Due to this, the performance of the outboard motor will reduce.
2) Wastage Of Funds
When fuel is put into the tank of an outboard motor, it requires funds.
But during a carburetor problem situation like leakage, some of the fuel will be lost due to the leakage.
This leads to wastage of fuel and wastage of funds too.
To avoid this, you have to make sure that you fix mercury 9.9 4 stroke carburetor leakage problems early when they occur.
This will help improve the performance of your mercury four stroke outboard motor and also avoid wastage of funds.