1985 Johnson 90 vro......too smoke

[delchilu]

My engine is ok now....but smoke too much.
Some tip?

 

[funpilot]

Re: 1985 Johnson 90 vro......too smoke

Delchilu,

Can you perform a compression test and post the results? Can you provide some information regarding the history of the engine? When was the last time the carbs were cleaned (and rebuilt, including float height), when was the last time the engine was decarboned. Do you ever run the engine at full throttle? Does the engine smoke just when it is idling or even under 1/2 or full throttle conditions?

And just on the chance... is your VRO system hooked up and working, i.e. do you put your oil in the gas, or do you put your oil in the small oil tank and let the VRO mix it with the fuel.

warmly,
fp

 

[delchilu]

Re: 1985 Johnson 90 vro......too smoke

Ok...I try to explain the story of my motor:

The carbs are cleaned and the spark plugs are new.
I checked the compression and is 95 psi for each cilinders. What does it means......decarboned ?
The engine smokes a full throttle 1/2 and during idling.
I am using the vro oil tank.

Another question....
Is normal that the trim pistons don't move togheter...better when I lower the motor...the pump start and before one and after the other the pistons move. Just the two rod are retracted the motor goes down.....is normal action?

 

[rickdb1boat]

Re: 1985 Johnson 90 vro......too smoke

Check to make sure all your fuel lines are tight. This includes the ones going to the VRO and the carbs. Any air leak in the lines will decrease fuel flow and excess oil will be injected into the cylinders causing smoke. This is more prominent at idle. Watch this video:

http://www.themarinedoctor.com/Vro.wmv ] Click Here [/url]

 

[funpilot]

Re: 1985 Johnson 90 vro......too smoke

If you have your motor in the supported, locked up position, the tilt and trim pistons may not retract in a coordinated fashion. When there is the weight of the engine on the pistons, they should move up and down together.

Decarbon means to run a cleaning agent through the engine (such as Seafoam Deepcreep) to clean out built up carbon. Carbon can cause sticky rings and subsequent engine failure. Your compression does sound good.

When the carbs were cleaned did you take them apart?

The video Rick recommended is pretty cool! definitely look for an airleak or a bad fuel line connection as well.

fp

 

[Dhadley]

Re: 1985 Johnson 90 vro......too smoke

What spark plugs are you using?

 

[wormboy]

Re: 1985 Johnson 90 vro......too smoke

I have a 1989 evinrude 150 XP that also had too much smoke. The VRO system on this engine is disconnected. Most of the problem was that the float in one of the carburetors was bent, so too much fuel was entering the carb and was getting into the exhaust without combustion--- and turning into fumes and smoke.
Take off the air silencer (cover) from the carburetors, pump the priming bulb (engine not running) and see if fuel starts coming out of the carburetors and the bulb stays hard.
From reading many helpful threads on my similar problem, it is usually not the VRO system that is the problem--- it is usually a leak in the fuel system that the VRO pump may be trying to compensate for-- or else a prblem with too much unburnt fuel in the exhaust like with my engine.
Pay attention to the experts, though-- i am a rookie!