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lubby_1

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just had my 9.8 merc on the bo

just had my 9.8 merc on the boat and noticed a problem.engine runs perfect in neutral and reverse but when in forward it severley lacks power.engine seems to bog down in forward when i apply some throttle.is their a govenor on these little guys or could this be a mechanical problem.serial#is 7088559.please help before i get passed by another 4 horse on the lake.
 
sounds like the main jet in th

sounds like the main jet in the carb is plugged or it could be running out of gas. Try pumping the fuel bulb while running at full to see if it helps. Then remove and clean carb
 
"pulled the plugs and both hav

"pulled the plugs and both have good spark.pulled carb off and cleaned.there was a small amount of gunk in carb but not bad.noticed that top plug was dry and like new,could fuel be only getting to one cylinder and if so how could i fix."
 
"Yes, bad crankshaft seal or r

"Yes, bad crankshaft seal or read problem. With the plugs removed, spin engine by hand, listen for each cyl to go poof. The sound a 2 cycle makes. No poof and the air/fuel charge is going out the bottom or top."
 
pulled the plugs and spun the

pulled the plugs and spun the motor.can hear both cylinders go poof.compression is 98 on top and 102lbs on bottom.top of piston on bad cylinder seems to be wet but will not fire.is it possible it is not getting enough fuel or could in be not firing the plug under compression.
 
"care to try a cyl drop test f

"care to try a cyl drop test from TMD site.
Cylinder Drop Test
04/05/06 at 10:33:19 Instead of posting this each time I have to let someone know how to do it. Here it is.

Cylinder drop test is done this way.

When the symptoms show up on your engine.

1. Turn it off.
2. Remove ONE spark plug lead and ground it. <---Place bolt into it and allow it to touch the engine block.
3. Restart engine and see if the engine runs any different. If it does run differently, that cyl is most likely working properly and is not the problem.
4. Turn it off.
5. Replace the spark plug lead and remove a different one.
6. Follow the steps above until you isolate the cyl causing the problem."
 
"rotate the coils and try agai

"rotate the coils and try again, most common problem is a bad switchbox. Test compression before buying parts"
 
switched coils around and now

switched coils around and now the bottom cylinder is the one that dosent fire.i assume that means the coil is nfg.if so why does it have good spark out of the cylinder.
 
"I don't know, some times

"I don't know, some times things fail under a load test. As I said its usually the switchbox and thats more $. Try it and see."
 
"merc specs here for more trou

"merc specs here for more troubleshooting if you dont want to buy parts yet
http://www.maxrules.com/
tech specs in the middle, then troubleshooting,,, and look under tech assistance and then general troubleshooting guide, its a download"
 
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