1986 Mercury 115 six-cylinder will not run in the water

[Crazydave1243]

1986 Mercury 115 six-cylinder will not run in the water. It will Run fine on muffs but will not idle in the water the only way to get the boat to move is Revit up in neutral and drop it into gear if you try to just ease into gear it will die every time i'll check the compression replace the fuel line and drained all the old fuel out of the tank still cannot get this thing to run on the water any thoughts are appreciated

 

[racerone]

It only sounds " fine " to you on the trailer.--------It might be as simple as opening the low speed needles 1/2 turn each.-----------Check for spark on all leads too.------Ruptured diaphragm in fuel pump ?--------And yes report the compression numbers.

 

[Crazydave1243]

I will and thank you. When you say 1/2 turn which screws are you referring to. I have yet to check I'll six cylinders I check the dreaded number one and number three they were both well above 120

 

[Crazydave1243]

One more thing if I pump the primer bulb I will get fuel running from the carbs

 

[racerone]

The human hand can generate more pressure than the fuel pump on the motor.---Any leakage when motor is running ?----The idle needle screws are on top right hand side looking straight at the carburetor.

 

[Crazydave1243]

Ok I checked the compression its around 110-115 on all cylinders. I also checked to make sure there was fire on all cylinders which there was. Would there be a diffence with in or out of the water? I sprayed the carbs down with cleaner and removed the drain plug in the top two carbs couldn't get to the bottom one. Still will not idle in the tub. Checked the fuel pump there was some trash in the screen. Any other ideas in all out of ideas thought it may be the low speed triger but spark seemed good at a idle.

 

[Georgesalmon]

Those are not drain plugs they are covers over the main jets. Sounds to me like you need to clean and rebuild the "INSIDE" of your carbs.

 

[Crazydave1243]

Just a fast update I may be wrong but I noticed a day if I manually move the timing arm it will idle up and smooth out is there anyway itcould be a link Sync. also it feels like the return spring and the timing mechanism is broke or not making connection there is a lot of play in the timing arm and is not springing back like I think it should

 

[Willdiver]

To be honest, the carb kit is pretty cheap. I ordered floats, carb kits, and pump kit from iboats, and it just arrived today. Do that, run a link n sync, and it should even out pretty nicely.

Will