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9.9 wont start

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dtsnell4

New member
I have an early 90's 9.9 mercury 2 stroke that a friend gave to me. Sat in his garage for about 2+ years. I got it started but it ran a little rough, so I figured I would clean the carb as it had been sitting so long. Took the carb apart, it was in really good shape all things considered, cleaned it and put it back on.

Now the motor wont start. It will start for a second with starting fluid, but thats it. Took the carb apart again but it doesnt look like I damaged anything.

Pulled the gas line off the carb to confirm that gas was getting there. When I prime the ball in the gas line, gas is getting there. However after I try to start the engine for a little while, i would take the gas line of the carb again it would be dry. Does this mean my fuel pump isn't working, or am I incorrect in thinking gas should still be in the line immediately after trying to turn the motor over?

If not, any other thoughts as to what I should try next?

Thanks in advance for any advise.
 
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The manual fuel pump ( aka primer bulb ) pumps fuel into the carburetor right through the pump.---------Check for strong spark on both cylinders.------Ckeck compression.
 
So you're saying the motor should start with me just priming the bulb, so the fuel pump isn't the issue. Got it. I can borrow a compression gauge from a friend. I held the wires in my hand while starting it and got a nice shock. Is that sufficient or is there a tool to test the spark? sorry if thats a dumb question.
 
Most shops have a tool where spark is checked across an adjustable gap ( up to 1/2" )----laying a plug on the block is a test but not a good test.-------------Right , the fuel pump keeps the motor running once it has started.---------Has nothing to do with actual starting.--------The primer bulb is nothing but a manual fuel pump.
 
...so I figured I would clean the carb as it had been sitting so long. Took the carb apart, it was in really good shape all things considered, cleaned it and put it back on.
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W/all due respect, did you set the throttle to full choke? After pulling the rope a few times did you squeeze the ball again? Remove the spark plugs and spray a shot of Seafoam into the plug holes, reinstall the plugs and give her a pull. If it fires but won't run you need to reclean the carbs. Check for dried varnish blocking the fuel line connector on the engine male connector.

There had to be some dried fuel varnish in the idle circuits. What did you use to clean it and how long did you soak it? Did you blow out the fuel passages w/compressed air?
 
The carb looks brand new at this point. There is no apparent varnish blockage, compressed air passes through everything.

Its the model with the shifter on the tiller, it has the primer/fast idle knob on the front of the housing, and it is working correctly. The primer button sprays fuel into the block, which must mean fuel is getting to the carb. I'll check the compression, spark, and I will try Seafoam, didnt think of that.

Sorry for my ignorance, but what are idle circuits? I cant find a reference to them in the service manual.
 
Sorry for my ignorance, but what are idle circuits?
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Anyone that asks a question is not ignorant. Idle circuits are the small fuel passages within the carburetor that feed the idle jet(s). Have you tested the stator and trigger coil w/an ohmmeter? Do that if a spark gap test fails to jump 7/16".
 
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