Yes, there is a rubber gasket. You can test it by running the engine for pressure, and it will all depend on where the break occured. It is possible that the plug was cross threaded, and therefore may keep the seal.

Safety says don't drive it untill you get a new plug.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K