Merc 9.8 fuel circuit

[PaulSidiro]

Hi all,
Thanks for all the info on the forums. I have spent the last 2 days running through troubleshooting of my 80's 9.8 2 stroke to try and get it started. No dice so far. I've gone through a dozen threads so similar issues but none exactly like mine.

What I've done:
-compression good
-completely disassembled and cleaned carb ( multiple times )
-set carb to stock spec
-new spark plugs
-confirm spark
-checked for leaking hoses and replaced any suspected leaking
-rebuild kit on the fuel pump gaskets.

What I've found:
-when I drop a few cc's of fuel in the cylinders it fires up and runs for a few seconds
-there is no fuel entering the cylinders
-premier bulb works and when firm and squeezed further will overflow fuel through the air intake nozzle
-fuel supply check valve is functional
-pulse check valve seems ok but can't check with engine off ?

I've got a sore shoulder pulling this thing and trying to start it the last few days

Please. If any one can give me some tips on where to look and replace I would greatly appreciate it.
I am using a 50:1 ratio of new fuel and oil.

Best regards,
Paul

 

[racerone]

Check reed valves.-----Checked upper and lower crankshaft seals ?---Does spark jump a gap of 3/8" or more , yes or no ?

 

[PaulSidiro]

Hi racerone, thanks.
Spark doesn't jump I just tested the plug grounded to the head.

I will look at the reeds next.
Can I access these from the intake or exhaust side?

 

[PaulSidiro]

The latest saga: I rebuilt the fuel pump and replaced the carb gaskets with a Sierra Kit. Put everything back and tried again.

Still no start. Tried some starter fluid through the carb intake and she fired up a bit and dies.

Interesting thing is I see that there is what smells like stale fuel dripping out the exhaust propeller area after I flood the cylinder with new premix. I'm thinking that the previous owner put this motor away wet and stagnant fuel has been sitting in there for a couple years. Perhaps this is the cause of the no-start?

I've put some water remover in the cylinders and left it overnight. Will try again after my shoulder recovers and give it more good pulls and see where that takes me.

Summary:
Good spark
Good compression
Good carb
Been sitting for 2 years wet with old fuel
Starts when cylinders are primed and then dies
Start with start fluid and then dies

Any further feedback? I want to avoid having to tear this motor down. Not worth it at this point.

Cheers
Paul