2008 F15M Mercury only running on 1 Cylinder

[BoatBug]

Ahoy,

I have a 2008 F15M Mercury 4 Stroke

it’s only running on the bottom cylinder
fuel is running out the overflow
I have replaced plugs and ignition coil

hope for you help and ideas

Boat Bug

 

[racerone]

Post compression numbers.---Check for strong spark on both leads-----But the fuel leak suggests looking at carburetor float and float valve.

 

[BoatBug]

Post compression numbers.---Check for strong spark on both leads-----But the fuel leak suggests looking at carburetor float and float valve.

i am getting 60 psi on both
this seems low ?

 

[racerone]

Throttle open ?-----Readings are way too low.

 

[BoatBug]

Throttle open ?-----Readings are way too low.

sorry both 160 PSI open throttle

 

[BoatBug]

I pulled apart carby I looked at the float and valve they seem ok
what part fails ?

 

[BoatBug]

sorry both 160 PSI open throttle

Is 160 PSI ok when cold ?