I have a oil pump leak on my 1998 subaru 2.5l outback. I have taken it apart three times. The first time I replace the o-ring and gasket. I used a high temp silicon gasket. It still leaked. I'm pretty sure it is leaking around the bottom bolts close to the o ring because there is no oil residue above these bolts. I took it apart again and used an anaerobic gasket and it is still leaking. I think the gasket might be failing inside near the o ring. I'm wondering if there is some other type of gasket material I should use. Or if I should put something on the bolts.

 

Thanks in advance!!

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