Oil Filter Adapter
Inspect the adapter fitting and bolt for damaged threads (Figure 2-149). Replace either fitting if damaged. Inspect the filter adapter for stripped or crossed threads, cracks, and chipped sealing surfaces. Replace the adapter if damaged. Remove and discard the old O-rings and gasket from the bolts (Figure 2-149). Install new O-rings and seal on the bolt and lubricate them with engine oil.
Bypass Valve
Remove the two bypass valves (Figure 2-149), and inspect them carefully. Replace either valve if damaged, or filled with shavings and/or debris.
NOTE: The filter bypass and cooler bypass valves can be removed with a small hook tool.