1999 Johnson 70hp 100 psi compression

[nim713]

I was wondering if I can get some answers from a recent compression test. I have just done a compression test on my Johnson 70hp. All 3 cylinders came back at almost exactly 100 psi. Is that too low of a compression? is there anything i can do short of a rebuild to gain more? I just had the carbs rebuilt about a year ago. Any info about this would be appreciated.

 

[racerone]

Those cylinders do have a wee hole that bleeds off compression at cranking RPM.----So may not be bad at all.----Are you having running issues ?

 

[nim713]

On top end no. But when I am idle its pretty rough and I feel like it wants to bog down when Im getting up on plane. Has been known to stall if its low idle just past put in gear. I just checked compression as a precaution ad felt it might me low. I am kinda leaning torwards low speed adjustment right now. But open to suggestions

 

[oldboat1]

Carbed models have a slow speed needle, so you might be right. Not sure what the initial setting is -- guessing maybe 3 or 3 1/2 open(?) Sounds like you might want to nudge it a little richer (c.clockwise). Stalling when going into gear can indicate too lean.