Lexus 13801-36020 Arm Sub-Assembly, Valve

This procedure requires engine and transaxle removal. Drain engine oil and coolant, then remove timing chains and sprockets. Ensure correct camshaft positioning before removal. Gradually remove bearing cap bolts, then housing bolts. Remove bearing caps and camshafts, and pry off camshaft housing. Remove and inspect rocker arms and lash adjusters. Check cam lobes and bearing journals for damage. Measure camshaft lobe and journal dimensions, replacing any outside specified limits. Check oil clearance for each camshaft journal, replacing if necessary. Lubricate and reinstall lash adjuster bores, rocker arms, camshafts, bearing caps, and housing. Apply RTV silicone sealer to sealing surfaces and tighten bolts. Repeat for front cylinder bank. Reinstall timing chains, cover, and components. Check for resistance by hand-rotating crankshaft. Refill oil and coolant, reconnect battery, start engine, and check for leaks.

1. Remove the engine and transaxle. 2. Drain the engine oil and coolant. 3. Remove the timing chains and sprockets.