engine lugs down at full throttle

lud2316

Recruit
Joined
Oct 16, 2004
Messages
3
I have a 1989 force engine[model#1258A9D] 125HP <br />Motor starts and runs fine when going out,but once it is shut off after running a while it starts up ok but doesn't want to idle and shuts down when taking off or trying to load it,Lugs down.Had it checked out at the boat repair shop.Compression ok-ign system ok-dyno tested ok.They just ran it at the shop not in the water.HELP
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,750
Re: engine lugs down at full throttle

Sounds like a classic case of fuel pump flooding.<br />Seems to happen alot, especially with 10-15 year old Force motors. Seems they didn't hold up to the new fuels on the market today.<br /><br />Basicly the seals, springs, and diaphram in the fuel pump get old and develope leaks. All is fine when you first run the cold engine.<br />When you turn it off for a while, the fuel leaks thru the pump, into the powerhead, creating a severely flooded condition ( possibly fouling the plug) in the lower cylinder when you turn the motor over.<br /><br />The good news is that the rebuild kit is less than $15 at any Mercury dealer, and you can do it yourself in about 30 minutes.<br />The kit comes with directions. <br /><br />This should probably be done anyway, on a motor of that age.<br /><br />I hope this solves the problem.
 

97trophy

Seaman Apprentice
Joined
Aug 18, 2004
Messages
35
Re: engine lugs down at full throttle

I had this same issue. I rebuilt the carbs for 12 dollars per and rebuilt the fuel pump. The engine now runs like a champ.
 

12Footer

Fleet Admiral
Joined
Mar 25, 2001
Messages
8,217
Re: engine lugs down at full throttle

Welcome to iboats, lud2316.<br />Check for a dead cylinder or two, if the motor runs fine in nuetral, but stalls under load.
 

lud2316

Recruit
Joined
Oct 16, 2004
Messages
3
Re: engine lugs down at full throttle

have ordered carburator rebuid parts can tell more after installing them
 

fixin

Senior Chief Petty Officer
Joined
Apr 23, 2004
Messages
775
Re: engine lugs down at full throttle

I would do fuel pump too,cheep and easy.
 
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