Sweet Johnson, except

[oakhill2009]

My 1992 50 Hp VRO equipped motor is a real trouble free work horse. My only beef with the outboard is at idle. For the past eight years or more the engine will run extremely rich at idle, even to a point that one of the two cylinders will cut out periodically, but only at idle. During engine flushes a river of milky exhaust residue will flow from the propeller exhaust port and one cylinder will miss fire. Rev up the RPM's at bit and the situation will clear up. I feel that one cylinder is receiving more 2 cycle oil than the other. Are there any adjustment to the VRO pump or the Carbs I can make to correct this dilemma. If not I will live with it and continue to run this baby for another 10 years. Please send advice. Thanks John

 

[ob]

Re: Sweet Johnson, except

oakhill,There is an adjustable idle mix screw on your carbs.Depending on the model no. of the 92 50 hp the location is either on the side of the carb body or on the bottom .You can determine the open position of these by screwing them clockwise until they lightly seat counting the exact turns.A good starting point for preliminary adjustment is lightly seated clockwise and then opened 1 1/2 to 2 turns.A water submerged final adjustment will be necessary for optimal setting.You can use the engines present set point as a reference to return mix screw to if you have no luck in remedying idle situation.<br />There is also an idle fixed orifice located at the top face of the carb that should be removed and cleaned of any debris that may be causing even a minor restriction.A manual specific to your engine would be of great benefit in performing this adjustment if you are not familiar with the procedure.There is no adjustment of the VRO pump.<br /> If you have the model number of motor it would be helpful to post it so that the exact carb that your engine uses will be easier to identify.

 

[oakhill2009]

Re: Sweet Johnson, except

OB thanks alot for your time and advice. I will attack both your recommendations. First starting with the jet on the top of the carb. More than likely I have had a piece of debris in the passage for years. Secondly I will adjust the idle mixture needle valve you recommended. I know the problem is only on one of two cylinders so troubleshooting should not be to difficult...thanks again.....John

 

[steelespike]

Re: Sweet Johnson, except

I believe if there is a hole in the fuelpump diaphram gas will get in the cylinder that supplies the pulses to the pump this would cause a rich condition on that cylinder.