Oil shouldn't be blowing from the intake manifold. The engine EGR system may be plugged or there could be significant blowby. Have you checked for a vacuum leak in the carb base or throttle shaft? Does the 400 have the intake manifold the mounts under the valve cover, like the 360/390/460-series engines? Could be some leaks along the intake manifold to head also. Try uncapping the oil fill cap and run the engine, feel for the blowby there. <img src="/forums/images/graemlins/kewl.gif" alt="" />

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