1991 mercury classic 50

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
I have this engine and it boggs down before planning out. When I move the fuel line at engine to the side a little it leaks gas. Can this be the problem? I changed filter and cleaned carbs still no change. My bubble from tank was horizontal so I stood it up. Now it holds pressure can this be a fix? Runs but is holding back
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
At that age replacing all our fuel lines and fuel pump diaphragm/valve seals (a fuel pump kit) and the squeeze primer bulb (OEM Merc has fewer problems from respondents on here and arrow points toward the engine (direction of fuel flow) would be a great idea. Check your tank screen for crud. While apart look for pieces of hose. If so, do a carb kit dismantling the carb looking for little black critters. Ensure the carb work includes air pressure at any hole you can find.
 

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
I cleaned carbs and it cranks and idles perfect but when I give it throttle it won't run but 10mph. Boggs down when I throttle up and acts like it's trying to run better
 

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
I have a gas line running to the back at the engine and when I move the gas line to the left or right it looks a little gas is that normal or do I have a blown seal
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
No leaking gas externally from any gas line under any condition. Time for an upgrade and check for debris as I mentioned earlier.
 

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
I have taken it into the shop it had the carburetors clean new fuel lines gas tank cleaned carburetors cleaned and adjusted compression check new plugs new fuel pump new coil pack it runs great out of water when I put it in the water it'll take about a quarter of the throttle and start holding back and when I gas on it it just bogs down and won't take any gas at all it cranks perfect Idols perfect is just when you gas on it it bogs
 

jpcampbell

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Joined
May 22, 2017
Messages
13
The Boat Shop told me that somebody had upgraded the engine it had a high performance flywheel and some kind of plate behind the carburetor system that adjusted to Air and gas. He thought electric fuel pump would fix it we tried that but it does the same thing it runs perfect when you gas on it it'll start to pick up and then just bogs down and it won't run five miles an hour
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,032
??-------Never heard of a " high performance flywheel "-----Sounds like the low speed jets need to be opened 1/8th turn at a time.-----That wee procedure often cures a bogging MERCURY.
 

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
have a 1989 Mercury classic 50 it runs and idles and cranks perfect when I gas on it it doesn't want to take any power I have had the tanks cleaned the carburetors rebuilt a new power pack put on new plugs and when I crank it I drop it in gear when I give it to gas it just acts like it's hitting on one or two cylinders I crank it up in the yard and pulled the each plug wire off and number two didn't really face the engine at all when I pulled it off
 

quicktach

Petty Officer 1st Class
Joined
Aug 24, 2012
Messages
394
Shouldn't be leaking any gas. You could also be sucking air which won't help things....
 

jpcampbell

Cadet
Joined
May 22, 2017
Messages
13
I have a 1989 50 classic Mercury 2 stroke I've had the carburetors rebuilt you power pack you spark plugs your gas tank you fuel line it cranks and idles perfect drop it any gear that it idles great you get out past the buoy throttle up on it it'll bog down for about 2 minutes and then slowly start picking up speed again can anybody give me some advice on this?
 
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