Mercury-Mercruiser 8M0187378 Quicksilver Longblock 8.1 HO 2001 and Up

8M0178378 Quicksilver Value Series New Longblock. Superseded from part number 8M0137121
8 Cylinder 8.1 Liter, 496 High Output V‑8 (Left‑Hand Standard Rotation)

100% New Content - 3 Year limited warranty in the USA

Replaces 2001 & up 496 Mag H.O. & 8.1L H.O. MerCruiser, Mercury Remanufacturing, & Quicksilver High Output engines. Also this service block can be used with other makes of engines.

Engine Features:
Heavy Duty Iron Block with Splayed 4‑bolt Main Bearing Caps
Priority Main Oiling System
8.6:1 Hypereutectic Pistons
Roller Camshaft
1.7:1 Rocker Arms
Forged Steel Crankshaft and billet oil adapter.

Quicksilver Iron Cylinder Heads feature Black‑X Valve Technology, hardened seats, and shot peened marine valve springs.

420 & 425 HP 100% New Quicksilver Marine Engine

Parts that will need to be transferred or purchased separately

• Balancer
• Flywheel
• Spark Plugs
• Distributor
• Water pump
• Manifold gasket set
• Quicksilver Synthetic Blend 25W‑40 4‑Stroke Oil