1972 OMC 60HP Help

[kamikaze]

Hey guys I need some help.

I have a 1972 60hp OMC three cycle that surges like it not getting enough gas at high speed (4200 - and above) but the primer bulb is solid and squeezing backs no difference. Motor is making good power all along - just feels like it leans out at high speed. If you run it a lower speeds no problem. Here what I've done to the motor to date.

Compression is 130 in all three holes.
Rebuilt carbs
Replace fuel pump/and gas lines
New CDI amplifier
New points
New plugs
Checked timing/TDC and there all good.


One additional problem I noticed to day is at low speed the (1000 - 1200 rpm) the tach will occasionally spin the needle right around the dia making a 360 rotation before it settles back on correct RPM. Not sure if this some other problem or perhaps related to the issue I'm having at speed?

Any suggestions/ideas....