| WARNING ALUMINUM CYLINDER HEADS ARE HIGHLY POLISHED AND MUST BE HANDLED WITH EXTREME CARE. AFTER REMOVING THE HEAD BOLTS, WITHDRAW THE HEAD FROM THE ENGINE COMPARTMENT. USE EXTREME CARE NOTING THAT THE GASKET SURFACE OF THE HEAD COULD BE DAMAGED ON THE WAY OUT OF THE VEHICLE IF ALLOWED TO HIT AGAINST OTHER ENGINE COMPONENTS. ONCE REMOVED, PLACE THE HEAD ON A BENCH, GASKET SIDE UP, USING A PIECE OF CLEAN CARDBOARD ON THE BENCH SURFACE UNDERNEATH. DO NOT SLIDE THE HEAD GASKET SURFACE ALONG THE BENCHTOP OR DAMAGE WILL OCCUR.
NOTE SOME ENGINES REQUIRE A "DE-TORQUING" PROCEDURE OF THE CYLINDER HEAD BOLTS. CONSULT WITH THE APPROPRIATE MODEL YEAR WORKSHOP MANUAL FIRST, AS THIS PROCEDURE IS USUALLY DONE ON FOUR-VALVE ENGINES. HOWEVER, ALL ALUMINUM HEADS ARE PRONE TO WARPAGE DURING REMOVAL IF TAKEN OFF WHEN HOT OR WARM. THE ENGINE SHOULD BE COOLED SUFFICIENTLY BY THE TIME THE HEADS ARE ACCESSIBLE DURING TEARDOWN. ALLOW AN ADEQUATE COOL DOWN PERIOD.
NOTE IN SOME ENGINE APPLICATIONS, IT MAY BE NECESSARY TO "RUBBER BAND" A FEW OF THE HEAD BOLTS TOGETHER DUE TO TIGHT CLEARANCES OF THE HEAD NEAR HEATER/AC PLENUMS AND THE BODY COWL. THIS WILL ALLOW THE BOLTS TO CLEAR THE BLOCK DECK AS THE HEAD IS WITHDRAWN FROM THE VEHICLE.
Place CLEAN shop towels over the cylinder block bores to prevent further contamination from reaching internal parts and surfaces. If a towel is to be removed, do it SLOWLY . Debris collected on the towel can fall on the engine if care is not exercised as it is removed.
Gasket surfaces are machined to near-mirror surface quality. Scratches, dents, gouges, and other impressions may allow oil, coolant, and compression gases to leak into other sealed cavities and/or the atmosphere. Surface imperfections deteriorate the head gasket's ability to seal effectively. Contamination on these surfaces will cause leaks from "shimming" the head even under full head bolt torque. Contamination will also cause marks on the polished gasket surface, creating a leak path.
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