Oil Filter By-Pass Valve And Adaptor 3A-86; Inspection And / Or Replacement 3A-86 - Mercury MerCruiser MCM 454 Mag MPI Service Manual

454 CID (7.4L) / 502 CID (8.2L)
Oil Filter By-Pass Valve and Adaptor
Engine with front mounted vertical oil cooler MUST have a 30 psi oil pressure relief
valve installed. Severe engine damage or failure will occur if not installed.
Inspection and / or Replacement
Oil by-pass valve and adaptor should be inspected whenever engine is disassembled for
major repair or whenever inadequate oil filtration is suspected.
Refer to "Engine Parts List" when ordering parts for oil filter by-pass valve, adaptor assembly
or remote oil filter parts.
1. Remove oil hoses from adaptor.
2. Remove hose fitting and seal from adaptor.
3. Remove connector.
4. Clean parts in solvent and blow dry with compressed air.
5. Inspect fiber valves for cracks or other damage. Check that valves fit tightly against
seats. Push each valve down and release it. Valves should return freely to their seats.
If valve operation is questionable, by-pass valve should be replaced.
Typical By-Pass Valve and Adaptor
6. Wipe out valve chamber in cylinder block to remove any foreign material.
7. Install by-pass valve (if replaced) and connector. Torque adaptor nut to 20 lb-ft (27 Nm).
8. Lubricate adaptor seal with engine oil. Install hose fitting and torque to specifications.
9. Apply Perfect Seal to hose threads. Install and tighten securely.
Index
Page 3A-86
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a - Fiber Valves (Ensure That Valves Fit Tightly Against Their Seals)
CAUTION
a
SERVICE MANUAL NUMBER 23
72546
90-861326--1 MARCH 1999