johnson high idle

[steven]

ok i have had alot of posts on a 150 johnson lets just forget them i finally run the numbers and it is a 1995 150 johnson and i need help trying to figure out why it is idling high at like 2000 rpm any ideas also wats a good compression reading for it im getting areading of 105 on all 6.

 

[Chris]

Well if you have 105 across the board that's a good sign.

I'm not sure what it should be brand new, (probably a bit higher I would think) but even if the compression is off a slight bit from new, as long as it's even across the board than you'll probably be ok.

For the idle, I would make sure that the slow speed jet(s) are adjusted properly. Usually turning them in, increases the RPM's and turning them out lowers the RPM's.

-Chris

 

[steven]

thanks ive just got to get the time to check it out lol im sure it wouldnt but just to be sure having the air box off wouldnt cause it would it.

 

[Chris]

thanks ive just got to get the time to check it out lol im sure it wouldnt but just to be sure having the air box off wouldnt cause it would it.

Having the air box off might effect it a bit actually.

If you have a good service manual, they typically tell you to gently seat the low speed-jets and then they give you a general guideline as to how many turns out to turn them. After that, you fine tune them when the motor is running.

-Chris

 

[steven]

thats a problenm i dont have a service manule does any one know where i find this info online.

 

[steven]

well i think i found my problem yay, i took the carbs off again to check them again and i found that the last time i put them back on i my gasket fell out of place and pinched it good so im 99.99999% positive thats the issue......... thank for the inputs