Airframe and powerplant technician reported the primer nozzles close to the #1 cylinder intake gasket on some Lycoming O-320-D3G engines are prone to inducing leaks which could result in engine failure in flight.

Narrative

I have discovered after multiple inspections on various Lycoming O-320-D3G engines with primer nozzles close to the cylinder #1 intake gasket; the nozzles are prone to inducing leaks in the intake possibly causing rough running engines or failure in flight; I propose an airworthiness directive requiring inspection of cyl #1 intake gaskets on all O-320 models with the primer line above the #1 intake gasket every 100 hours or a mandatory relocation of the cylinder #1 primer line.