EXCESSIVE smoke…

ryanp1227

Petty Officer 3rd Class
Joined
Apr 17, 2022
Messages
78
1988 Mercury 9.9hp two stroke. About 2 years ago it was great, had not started it since then until today. Was stored horizontally on the floor, carb side down, with no fuel in the bell. Prior to starting, I replaced the water pump, gear oil, spark plugs, fuel filter, thermostat, and filled up new gas with a 50-1 mix and a couple ounces of seafoam. Motor started right up and was smooth, but it was immediately smoking badly. Smoke from the exhaust, tell tale, and where the shift rod goes into the lower unit. Smoking got worse as RPMs increased. Also was not pumping water.

Shut it down, dropped the lower unit again, confirmed the impeller was oriented correctly and the key was in place. Shot a stream of water thru the intake above the prop and water streamed from the tell tale. Put it back together, checked over everything, and started again. Started right up, smooth idle and throttle advance, still excessively smoking (like cant see the motor when standing right next to it thick smoke when giving it throttle), and still no water from tell tale.

Any thoughts?
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,082
1988 Mercury 9.9hp two stroke. About 2 years ago it was great, had not started it since then until today. Was stored horizontally on the floor, carb side down, with no fuel in the bell. Prior to starting, I replaced the water pump, gear oil, spark plugs, fuel filter, thermostat, and filled up new gas with a 50-1 mix and a couple ounces of seafoam. Motor started right up and was smooth, but it was immediately smoking badly. Smoke from the exhaust, tell tale, and where the shift rod goes into the lower unit. Smoking got worse as RPMs increased. Also was not pumping water.

Shut it down, dropped the lower unit again, confirmed the impeller was oriented correctly and the key was in place. Shot a stream of water thru the intake above the prop and water streamed from the tell tale. Put it back together, checked over everything, and started again. Started right up, smooth idle and throttle advance, still excessively smoking (like cant see the motor when standing right next to it thick smoke when giving it throttle), and still no water from tell tale.

Any thoughts?
Did you rebuilt the carbs?
Replace the needle values and adjust the flats?
A stuck needle will cause this condition
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,833
Motor running in a test bucket with water 6" above the impeller ?
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,833
Well----The water pump impeller must be SUBMERGED as these pumps are not self priming.-----Launch the boat or get a bigger test bucket !
 

ryanp1227

Petty Officer 3rd Class
Joined
Apr 17, 2022
Messages
78
Well----The water pump impeller must be SUBMERGED as these pumps are not self priming.-----Launch the boat or get a bigger test bucket !
Im aware. I thought having it 4” under would be sufficient. Working on a fix
 
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