Hard starting 4-stroke
 

Took my Yamaha 9.9 4 stroke out of storage (after 2 years) and tried to start it today.
It would not catch until I sprayed in some starting fluid, but then it would only
rev up a bit and then die. I think it is getting sufficient fuel from a supply tank,
but that is one thing to check. I ran the engine dry and fogged the carburator when I put
it away last time. Could the fogging material be blocking one of the jets? Do I have
to remove the carburator from the engine to clean it, or can this be done with the
carburator attached to the engine? I was using fresh fuel, and this is an almost new
engine, with about 20 hours on it. Somewhere I saw a recommendation to partially
or fully cover the air inlet to assist in getting fuel to the engine. Is that a good idea?

Sherwin D.

Sounds like no fuel to the motor. Is the fuel bulb pumped up hard. And
there is a choke on the front of the motor, at least on my T-8, that does
the job of covering the carb inlet.

"sherwindu" wrote in message
...
Took my Yamaha 9.9 4 stroke out of storage (after 2 years) and tried to
start it today.
It would not catch until I sprayed in some starting fluid, but then it
would only
rev up a bit and then die. I think it is getting sufficient fuel from a
supply tank,
but that is one thing to check. I ran the engine dry and fogged the
carburator when I put
it away last time. Could the fogging material be blocking one of the
jets? Do I have
to remove the carburator from the engine to clean it, or can this be done
with the
carburator attached to the engine? I was using fresh fuel, and this is an
almost new
engine, with about 20 hours on it. Somewhere I saw a recommendation to
partially
or fully cover the air inlet to assist in getting fuel to the engine. Is
that a good idea?

Sherwin D.

"sherwindu" wrote in message
...
Took my Yamaha 9.9 4 stroke out of storage (after 2 years) and tried to
start it today.
It would not catch until I sprayed in some starting fluid, but then it
would only
rev up a bit and then die. I think it is getting sufficient fuel from a
supply tank,
but that is one thing to check. I ran the engine dry and fogged the
carburator when I put
it away last time. Could the fogging material be blocking one of the
jets? Do I have
to remove the carburator from the engine to clean it, or can this be done
with the
carburator attached to the engine? I was using fresh fuel, and this is an
almost new
engine, with about 20 hours on it. Somewhere I saw a recommendation to
partially
or fully cover the air inlet to assist in getting fuel to the engine. Is
that a good idea?

Sherwin D.



Yamaha 4-stroke 9.9 has very small carb passageways and yours may also have
the "automatic choke" on it. Almost invariably leftover fuel in the carb
will gum up inside, blocking or restriction fuel flow. Running a motor out
of gas does not get rid of everything in the carb. The owners manual
recommends the use of a fuel stabilizer to minimize the problem.

Ask any repair facility, in the spring, most repairs are carb cleanings due
to today's fuels decomposing and leaving tar-like deposits.

Chances are you will need a complete carb cleaning and a repair kit for your
motor.

Bill Grannis
service manager

As an update to my posting,
In preliminary discussions with outboard mechanics, they point the finger at the extremely fine
jets in the 4-stroke engines. One mechanic said gasoline dries to a powdery residue, which then can
become imbedded in these jets. This problem seems peculiar to 4-stroke engines. My former
2-strokes never needed a carburator cleaning or rebuild. Why is this sensitivity of 4-strokes one
of the world's greatest secrets? I would have taken extra pains to run something like 'Stabil'
through the carbs before storing the engine. I might have not bought a 4-stroke if I thought they
would be so problematic. I checked the engine today and gas is definitely coming out of the hose
that supplies the carborator. I will probably have to get my boat towed to the nearest mechanic.
I hope they don't have to remove the engine from the boat to do this job.

Sherwin D.


sherwindu wrote:

Took my Yamaha 9.9 4 stroke out of storage (after 2 years) and tried to start it today.
It would not catch until I sprayed in some starting fluid, but then it would only
rev up a bit and then die. I think it is getting sufficient fuel from a supply tank,
but that is one thing to check. I ran the engine dry and fogged the carburator when I put
it away last time. Could the fogging material be blocking one of the jets? Do I have
to remove the carburator from the engine to clean it, or can this be done with the
carburator attached to the engine? I was using fresh fuel, and this is an almost new
engine, with about 20 hours on it. Somewhere I saw a recommendation to partially
or fully cover the air inlet to assist in getting fuel to the engine. Is that a good idea?

That didn't help.



Sherwin D.