2. Oil Leaks (M30)
Symptoms
Oil weeping from the valve cover gasket, oil filter housing gasket, oil pan gasket, rear main seal, and front crank seal. Oil residue on the underside of the engine and on the exhaust manifold.
Cause
Cork and rubber gaskets degrade over decades. The oil filter housing gasket, a large O-ring that seals the filter housing to the block, is the most critical because it leaks directly onto the exhaust manifold.
Fix
Full reseal.
Valve cover gasket ($15-25, 30 minutes), oil filter housing O-ring ($8-15, 1 hour), oil pan gasket ($25-40, requires lifting the engine slightly, 3-4 hours), rear main seal ($20-30, requires gearbox removal, 6-8 hours).
Workshop cost for full reseal: $1,000-2,000.
Prioritise the oil filter housing gasket, oil on the exhaust manifold is a fire hazard.
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