1995 150hp merc

[wyeknot]

I recently purchased a 1985 v-20 steplift with a 1995 150hp merc and am very happy with them except...First, the engine runs great at high speed but at idle it runs quite rough,someone told me that some of the cylinders drop out at low speeds and that it normally runs rough -but I'm not so sure-it shakes alot and almost stalls.Second , the power trim is getting water in it -what is one to do about this -thanks

 

[andy6374]

Re: 1995 150hp merc

What are your RPM's at idle speed, or the speed at which it is running rough? <br /><br />The first place I would look is at the carbs, have they ever been cleaned? Are the throttle shutters in the carb throats closed all the way at idle. Even if just one of the throttle shutters is open a little bit it will cause a rough idle. If this all checks out we will move from here.<br /><br />As far as water in the trim, I'm sure someone else can give you some help.<br /><br />-andy

 

[papasmurf]

Re: 1995 150hp merc

Usuall if water is getting into the trim system you would see oil leaking out. Any leaks? How did you determine that water was entering the system? The only motor I'm aware of that "drops" any cylinders at idle ,is the big 4 cylinder inline motor.

 

[wyeknot]

Re: 1995 150hp merc

Originally posted by andy6374:<br /> What are your RPM's at idle speed, or the speed at which it is running rough? <br /><br />The first place I would look is at the carbs, have they ever been cleaned? Are the throttle shutters in the carb throats closed all the way at idle. Even if just one of the throttle shutters is open a little bit it will cause a rough idle. If this all checks out we will move from here.<br /><br />As far as water in the trim, I'm sure someone else can give you some help.<br /><br />-andy

 

[wyeknot]

Re: 1995 150hp merc

thanks for the advice i'll check the carbs. i did see milky oil coming out of the top of the pump',i'll replace the seal and oil on the trim piston