VP D2 55/75 Turbo Waste-gate Opening

[David1]

Hi
I've researched various threads on the Volvo Penta D2 waste-gate seizing issues.

My D2 waste-gate opens and snaps shuts by the return "spring" action. However, when its fully open, its travel is limited by the exhaust elbow (as my dented 0.01mm feeler gauge indicates).

My Question is how much should the waste-gate open? I know other owners have ground the exhaust elbow casting to allow more clearance.

Mine moves the actuator rod by 3-4mm is that enough? My guess on the waste gate arm rotational movement would be that it moves more than 10 but less than 30 degrees. Is this correct???

Thanks