Sierra 18-449 Boat Cylinder Head Fits 2.5L/3.0L GM (1968-95),non-Mercruiser LX Models 1968-95. Condition is "Brand New". Condition is Brand New. Brand: Sierra Model: 18-4489 Shipped with USPS Priority Mail Or UPS Ground Either At Sellers Option . You Will Receive 1 ea Model: 18-4489 Sierra cylinder boat head assembly for Mercury Marine boat engine. RARE VINTAGE COLLECTIBLE SHIPS N 24 HOURS Packed By Our Award Winning Packaging And Shipping Department Long Time E-commerce Seller For Over 20 Years LIMITED AVAILABILITY Inventory Box Number: 3 Bay Warehouse Door #1 Additional Information; Features Sierra cylinder head assembly for Mercury Marine engine. Fits 2.5L/3.0L GM (1968-95), non-Mercruiser LX models (1968-95). Sierra Part #18-4489. OEM Part Numbers: 936-986767 936-5544 936-810840 Show more Sierra Part #18-4489 Cylinder head assembly For Mercury Marine engine Replaces 2.5L/3.0L I4 GM 1968-95 (non MerCruiser LX models) 1968-95 Brand:Sierra Marine Manufacturer's Part Number:18-4489 Part Type:Cylinder Heads Summit Racing Part Number:RRA-18-4489 UPC: 808282228781 Key Features: New stainless steel valves, hardened steel exhaust seats, valve springs, valve locks and retainers GM cyl. heads utilize high performance screw-in rocker arm studs in place of factory press studs Fits: 2.5L/3.0L GM (1968-95) Cross References Mercruiser Stern Drive 936-5544 Mercruiser Stern Drive 936-810840 Mercruiser Stern Drive 936-809890 Mercruiser Stern Drive 938-8M0115134 Mercruiser Stern Drive 938-8M0115135 Mallory 9-59000 Fitment Information Mercruiser 120 GM 1983-1986 120hp 4 stroke 2.5 liters 4 cylinders 153 cid 140 GM 181 I/L4 1968-1986 4 stroke 3, liters 4 cylinders 181, cid 2.5L GM 1983-1989 120hp 4 stroke 2.5 liters 4 cylinders 153 cid 3.0L GM 1983-1995 140,hp 4 stroke 3 liters 4 cylinders 181 cid 3.0LX GM 1990-1995 4 stroke 3 liters 4 cylinders 181 cid Description Sierra Cylinder Head Assembly for 2.5/3.0L (1968 - 95) Fits: 2.5L 3.0L GM (1968-95) (non MerCruiser LX models) (1968-95) NON-VORTEC Features: Hardened Steel Exhaust Seats Threaded Rocker Studs Assembled with Stainless Steel Valves, seals and springs Casting Numbers: 954, 748, 950, 758, 087, 852, 531 Note: Engines made between 1968-1982 use manifold to head gasket BARCHV-47-0120, Engines made between 1983-1995 use manifold to head gasket 18-1204 Details Brand: Sierra Manufacturer Item Number: 18-4489 Engine Make: Mercruiser SIERRA 18-4489 CYLINDER HEADS All cylinder heads are new castings and complete assemblies with new- stainless steel valves, hardened steel exhaust seats, valve springs, valve locks, and retainers. All GM cylinder heads utilize high performance screw-in rocker arm studs in place of factory press in rocker arm studs. Replaces: MerCruiser 936-5544, 936-810840/986767 Fits: 2.5L/3.0L GM (1968-95) (non MerCruiser LX models) (1968-95) Cylinder Head Assembly 18-4489 Marine cylinder head assembly for GM 2.5L and 3.0L non-LX model 4 cylinder engines. For 2.5L 153 CID 3.0L 181 CID non-LX model engines from 1968-95 Replaces Mercruiser 936-5544 and 936-810840/986767