Volvo Penta 2002 Motor Surging

[albergsailor]

this thing surges worst at around idle, around 1700-2000 rpm its not really noticable(it cruises fine) But this problem has been driving me NUTS for about a week straight. Ive been dealing with the problem for the last 2 years as i had much more important things on the boat to fix. So i decided to try and tackle this problem head on this week and i have swapped out everything from injector pumps to injectors. I replaced all the fuel lines/fittings. I noticed yesterday very small air bubbles coming from the main return line into the tank(almost hard to see but im sure that i should be seeing only diesel right?. I just got a tip online about putting a clear hose on the main fuel line before the pump to watch for bubbles. Ive done that before thats how i knew i needed to have a water seperator hooked up on a diesel lol. I have an older raycore seperator with brand new filter/and have new engine filter. clear BRAND NEW diesel fuel is in the tank. I am very aware of the bleed process for this motor. I had a tiny leak in the small injector return line but i dont think that can suck in air?? I didnt replace the fuel lines with anything special i just used autozone cheap fuel line. SHould i have double clamped everything?? any ideas? thanks ahead of time, well im off to put a clear hose on the input line, ps i have the bosch injector pumps

[albergsailor]

fixed it!! the regulator bar that goes from injector pump to injector pump was ever so slightly bent, when i would check the movement of the bar with the motor on it seemed to move very easily but when the motor was off i noticed it was hanging slightly, i fixed the bar so the regulator moved the way it should and bam problem fixed. i didnt look so close at that bar at first because i had bought it used from another motor i took it out of myselff cuz i bent up my origional, I think i bought the used one slightly bent and didnt notice it.. going sailing today!