Mercury 9.8 has spark, won't start

jeff_32

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Aug 12, 2008
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I have a 1978 Mercury 9.8 that will not start. Has good spark, tried squirting gas/oil mixture in carb...nothing. Tried starting fluid in carb, nothing.

Is this a timing issue? How do I go about changing the timing.
 

jeff_32

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Aug 12, 2008
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44
How did it run for you last season?----What happened?
It always started up easily. Until one day it didn't and noticed bad wires coming out of the switch box. I attempted to fix them but not enough good wire. Replaced the switch box. Now I get great spark but will not start period.
 
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jeff_32

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Aug 12, 2008
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Although I have spark, could the trigger be the problem by throwing off the timing?
 

racerone

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Dec 28, 2013
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Put a few drops of fuel into each cylinder.----Put plugs back in.----Pull it over.-----Should bark / roar like a mad dog or lion.----If not try reversing plug leads.-----I say it is a timing issue.-----But you state that flywheel key has been verified good.
 

jeff_32

Seaman Apprentice
Joined
Aug 12, 2008
Messages
44
Put a few drops of fuel into each cylinder.----Put plugs back in.----Pull it over.-----Should bark / roar like a mad dog or lion.----If not try reversing plug leads.-----I say it is a timing issue.-----But you state that flywheel key has been verified good.
I tried to put gas/oil mixture through the carb again, nothing. I tried ether again...I know shouldn't do this...still nothing not even a cough. Pulled the plugs and put gas/oil in each cylinder and it fired right up. Then I was able to start it the rest of the day with barely a crank of the starter. Could a reed valve been stuck?

Thanks to everyone for all the help.
 

racerone

Supreme Mariner
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Dec 28, 2013
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There is more than one reed valve for each crankcase.----There are 4 reed valves for the top cyinder and 4 reed valves for the bottom cylinder.
 

saltchuckmatt

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Jul 19, 2019
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2,775
I tried to put gas/oil mixture through the carb again, nothing. I tried ether again...I know shouldn't do this...still nothing not even a cough. Pulled the plugs and put gas/oil in each cylinder and it fired right up. Then I was able to start it the rest of the day with barely a crank of the starter. Could a reed valve been stuck?

Thanks to everyone for all the help.
Whatever is was who cares....count your blessings!
 
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