Cold natured Johnson 150

[brad1945]

I have a 88 Johnson 150 (v6) that starts up easily but will not accelerate. You have to run at cold start until you hear the motor rpm's straighten out and then you can go the rest of the day. You will be running at a rough idle and then all of a sudden the motor will begin to run correctly. This normally takes a few minutes and you are not going anywhere until you feel the motor straighten up.

 

[Cricket Too]

Re: Cold natured Johnson 150

brad.....welcome to the post. When was the last time the carbs were taken apart, cleaned and rebuilt? It sounds like maybe you have a lean mixture condition which is causing the motor to idle rough when cold, then as soon as the motor gets a little heat in it the mixture is sufficient for the warmer motor and the idle smooths out. Check your plugs to see if any of them indicate a lean condition.

 

[brad1945]

Re: Cold natured Johnson 150

I have had the carbs off a couple of times and cleaned them. During the time it is warming up it also smokes bad but then as if you turned a switch on it will pick up rpms and will then be ready to go the rest of the day.

 

[DHPMARINE]

Re: Cold natured Johnson 150

Brad<br />How often to you use the motor?If it sits awhile,the fuel evaporates,leaving alot of oil in the system.When you use it again,the oil has to burn off first.<br />DHPMARINE

 

[brad1945]

Re: Cold natured Johnson 150

It has not been used that much. It had been sitting for over a year when I first bought it. I then had to take the carbs off and cleaned them before I could run it. Then it went thru a winter when I did not put any stabil in it and had to clean the carbs again. It will sit for a couple of weeks during the summer between uses. I changed the plugs one time and it ran perfect the first time I cranked it. The vro system has been taken off and I mix the oil.

 

[LubeDude]

Re: Cold natured Johnson 150

Im certainly not an outboard mechanic, but have a mechanical background! I personally think that what is happening is that it is just taking that long to get the oil burned off before it will pick up RPMs! With the injection disconnected you are running oil rich at idle anyway! Change plugs and change to a full synthetic oil and I think you will notice a big difference!

 

[Dhadley]

Re: Cold natured Johnson 150

Perhaps its not firing on all at first???