Sierra 18-70945 Molded Hose, Thermostat Housing to Port Manifold, Replaces 32-862139, Fits Mercruiser 4.3L (Gen+) 1998-07

The Sierra 18-70945 is a molded coolant hose engineered to connect the thermostat housing to the port manifold on Mercruiser stern drive engines equipped with a two-piece exhaust manifold. Rather than a generic length of tubing that has to be trimmed and clamped into a rough approximation of the original routing, this hose is molded to the factory bend and connection points, so it seats correctly against the thermostat housing and port manifold fittings without kinking or requiring extra hardware to hold its shape under engine heat and vibration.

It is built from glass (glass-reinforced) hose material in white, giving it the heat resistance and structural rigidity needed to handle the closed cooling system's flow between the thermostat housing and the port manifold. Sierra designs this hose to meet or exceed the performance of the original equipment part it replaces, and each package contains one hose. It directly replaces Mercruiser stern drive part 32-862139 and is intended for Mercruiser 4.3L (Gen+), 4.3L EFI (Gen+), and 4.3LH (Gen+) engines that use a two-piece exhaust manifold configuration. Because this hose is specific to the thermostat-housing-to-port-manifold routing, confirm your engine's manifold configuration and engine designation before ordering to make sure it matches your application.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-70945
• Product Type: Molded Hose
• Application: Thermostat Housing to Port Manifold
• Exhaust Manifold Configuration: Two-Piece Exhaust Manifold
• Material: Glass
• Color: White
• Weight: 0.68 pounds
• Package Quantity: 1 hose
• UPC: 808282265595

Fitment

• Mercruiser 4.3L (Gen+) (1998-07)
• Mercruiser 4.3L EFI (Gen+) (1998-01)
• Mercruiser 4.3LH (Gen+) (1998-02)

Replaces (OEM)

• 32-862139

Frequently Asked Questions

What does the Sierra 18-70945 hose connect? It connects the thermostat housing to the port manifold on applicable Mercruiser stern drive engines, and is molded specifically for engines with a two-piece exhaust manifold.

What OEM part does the 18-70945 replace? It replaces Mercruiser stern drive part number 32-862139.

Which engines is this hose designed for? The Sierra 18-70945 fits Mercruiser 4.3L (Gen+) (1998-07), 4.3L EFI (Gen+) (1998-01), and 4.3LH (Gen+) (1998-02) engines with a two-piece exhaust manifold.

Is the 18-70945 hose side-specific? Yes, this hose routes to the port manifold; it is not a universal port-or-starboard fitting.

What material is the hose made from? The 18-70945 is made from glass (glass-reinforced) hose material in white, chosen for heat resistance in the closed cooling system.

How many hoses come in a package? Each package of the Sierra 18-70945 includes one molded hose.

What color is the Sierra 18-70945 hose? It is white.

How much does the 18-70945 weigh? The hose weighs 0.68 pounds.

Does this hose fit engines with a one-piece exhaust manifold? The 18-70945 is specified for engines with a two-piece exhaust manifold configuration on the listed 4.3L (Gen+), 4.3L EFI (Gen+), and 4.3LH (Gen+) engines.

Is the 18-70945 a genuine Sierra part or generic aftermarket? It is a genuine Sierra part, molded to meet or exceed the performance of the original equipment hose it replaces (32-862139).

Does the 18-70945 fit 4.3L EFI models? Yes, it is designed for 4.3L EFI (Gen+) (1998-01) engines in addition to 4.3L (Gen+) and 4.3LH (Gen+) applications.

How is 18-70945 different from Sierra's other similar molded hoses, like 18-70953? The 18-70945 routes the thermostat housing to the port manifold on 4.3L-family engines, while 18-70953 is a separate part number for a seawater pump to oil cooler application on different engine fitments, so make sure you are ordering the part number matching your specific connection point.