idle adjustments on 85' Johnson 150

[bmurray]

sorry for all of the post, my manual is not in yet. How do you adjust the idle on this engine? When hooked up to the hose it is idling somewhere between 1000-1100 rpm's. I think I was told it shoulp be at about 800. thanks for any replies.

 

[hondon]

Re: idle adjustments on 85' Johnson 150

Idle speeds on these engines are generally set while in gear and on the water.Be carefull with the screw turning as you can do more harm than good without some guidance.

 

[ob1jeeper]

Re: idle adjustments on 85' Johnson 150

After several years as a faithful I/O boat owner, AND VERY MUCH to my Chagrin, It's been my experience that the ONLY things you can determine from running a Johnson 2-stroke outboard "on the hose" is:<br />1- that it starts, and<br />2- that the water pump is "pissing water"...<br /><br />Other than that... Unlike a 4-stroke I/O motor, NOTHING a Johnson two stroke does on the hose will match what it does on the water... BE CAREFUL when setting the idle !!! AND Good luck...

 

[R. Wood]

Re: idle adjustments on 85' Johnson 150

I'm not sure about your motor, but I initially set my idle to 1000 or so on the flushing unit.<br /><br />When I hit the water, the idle needed to be increased (but I had a lot of other issues not readily apparent when running on the flush)<br /><br />Don't bother setting idle on flushing unit.<br /><br />Last but not least, do rev past 2-3K on the flushing unit, you'll blow the exhaust to powerhead gasket (as I've learned!).

 

[R. Wood]

Re: idle adjustments on 85' Johnson 150

^ Typo above, for clarity DO NOT REV MOTOR on the flush.

 

[bmurray]

Re: idle adjustments on 85' Johnson 150

thanks all for your replies. I will keep the revs down. Also my base gasket is already in need of a replacement.

 

[ob1jeeper]

Re: idle adjustments on 85' Johnson 150

To: r. wood ( member # 10990) OK... So what physical manisfestation (what bad happens) when the exhaust to- Pwr head gaset blows ??

 

[R. Wood]

Re: idle adjustments on 85' Johnson 150

From my expierence the tell tale for me was in the lower "pan" of the motor, "gunk" everywhere.<br /><br />I can see puffs of white exhaust smoke coming from the interface. I also beleive it's spitting out water.<br /><br />Although I'm not sure to what degree this is effecting my performance, recirculation of the exhaust gas back into the carb (while cowling is on) can't help.