only run with choke

Disschord

Seaman Apprentice
Joined
Aug 28, 2013
Messages
40
Hi my mercury 2007 8hp 4 stroke will only run with choke I have pulled the carbs and striped and cleaned them. But I'm still having the problem

Any ideas people
 

G_Hipster

Petty Officer 2nd Class
Joined
Sep 24, 2016
Messages
131
I'm not familiar with that carb. You've missed something in the idle/pilot jet/ emulsion tube circuit. Called a choke , but normally it's an enrichener circuit and why it runs with it pulled.
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
As he said, you missed something in the cleaning, not uncommon.
 

G_Hipster

Petty Officer 2nd Class
Joined
Sep 24, 2016
Messages
131
Poke around the holes with a copper strand out of a piece of wire .
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,891
Poke around the holes with a copper strand out of a piece of wire .

With a good 100# compressed air blowout as your exit point.

If all that doesn't work try these two things:

Pump the primer bulb (attempting to pump fuel) and see if it gets hard with the engine off. If not, you have hose problems in the engine, usually a cracked fuel line or bad check valve in the fuel pump.

Then another fuel pump check: Run the engine and squeeze the bulb as you are running....it should partially collapse as you squeeze it as the engine is consuming fuel, but not collapse completely which would signal a problem at the bulb or toward the tank.....fuel hose degradation. Back to the action: If the engine picks up with you squeezing and you can quit "enhancing" and the engine runs better, much better, go after a fuel pump kit.
 
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25xs

Cadet
Joined
Sep 30, 2008
Messages
22
Agreed that some debris was likely missed during carburetor cleaning... on that engine, there are tiny passages in the float bowl so pay careful attention to clean and blow out (with compressed air) those tiny passageways inside the float bowl. If you have an exploded view of the parts used to assemble the carburetor, BE SURE that you have fully disassembled it. There will be orifices, tubes, etc... down in the bottom of holes that you can remove and clean.
 
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