50 hp mercury problem

butros

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Jul 28, 2010
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3
I have a 1985 4 cyclinder 2 stroke. Engine starts and idles fine but when giving throttle its bogs and will not plane out. Hitting the choke but makes it momentary pick up speed but then dies back down. Any suggestions..
 

Coloradolakeboy

Petty Officer 2nd Class
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Jun 21, 2010
Messages
197
Re: 50 hp mercury problem

Typically, when you can keep an engine going with the choke, you are basically giving it more fuel. You probably need to rebuild you fuel pump. Don't run it like this, it is too lean and could burn a piston. Check the fuel bulb, you could be losing fuel thru a bad check valve, unlikely but possible.
 
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jimdd810

Chief Petty Officer
Joined
Mar 18, 2006
Messages
532
Re: 50 hp mercury problem

I would look at rebuilding the carbs.
 

butros

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Jul 28, 2010
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Re: 50 hp mercury problem

Thanks for the imput..I removed the carbs , took um apart and cleaned them. Put back on and it runs like a champ. Replaced a few hose clamps while I was at it.
 

butros

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Jul 28, 2010
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Re: 50 hp mercury problem

Now new problem. Motor was running fine. Cut the switch off. Tryed to restart and nothing. Motor turns over fine but no spark. Had been running fine all that day. Started it several time through out the day. Then nothing. There is power going to the engine from the battery. But none of the plugs are fireing....
 

markplayn4life

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Jul 28, 2010
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Re: 50 hp mercury problem

I have a 1985 4 cyclinder 2 stroke. Engine starts and idles fine but when giving throttle its bogs and will not plane out. Hitting the choke but makes it momentary pick up speed but then dies back down. Any suggestions..
i have a 115 1990 mecury 4 cylinder 2 stroke.just replaced coil pack cleaned carbs,checked compression.runs fine at quarter speed,.so when you find out or anybody knows please tell mebut full throttle goes maybe 10 mph
 

jimdd810

Chief Petty Officer
Joined
Mar 18, 2006
Messages
532
Re: 50 hp mercury problem

check all your wires to make sure there isnt a short somwhere like the kill circuit. If you disconnect the kill circuit and get spark then theres your problem.
 
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