Possible Causes:
1. Damaged Oil Filter O-Ring:
- Inspect the oil filter O-ring located where the cylinder head meets the bottom of an oil filter can for damage or improper seating resulting in an oil leak.
2. Damaged oil passage plug:**
- Inspect oil passage plugs for being stripped or not screwed in all the way. These can get hit when replacing engine covers etc.
3. Incorrect Cylinder Head Gasket/improperly tightened cylinder head:**
- Verify if proper head gasket was used by part number/dimensions when assembling and if correct torque specs were applied.
