Sierra Freeze Plug 18-5961-9, 1-5/8 Inch Bronze, Interchanges with Mercruiser 19-34270, Pack of 8

The Sierra 18-5961-9 freeze plug is a bronze expansion plug sized at 1-5/8 inch, sold in a pack of 8. Freeze plugs (also called expansion plugs) seal core casting holes in an engine block or manifold and are a routine replacement item when servicing internal engine components. This Sierra plug is built to meet or exceed original equipment quality and is manufactured in the United States, giving it a direct, drop-in equivalence to the factory part it replaces.

Constructed from bronze with a gold finish, the 18-5961-9 resists the corrosion that steel or brass freeze plugs are prone to in a marine engine's wet, saltwater-exposed environment, which is why bronze is the preferred material for this application. It is designed to be interchangeable with Mercruiser Stern Drive part number 19-34270, making it a straightforward replacement when servicing Mercruiser internal engine components. Each pack contains 8 plugs of the same 1-5/8 inch size, so a full engine or manifold resealing job can typically be completed from a single package rather than sourcing plugs individually.

Sierra also offers this same freeze plug in a 1-3/4 inch size under a different part number, so buyers should confirm the bore size needed before ordering.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5961-9
• Size: 1-5/8 inch
• Material: Bronze
• Color: Gold
• Package Quantity: 8 freeze plugs
• Weight: 0.61 pounds
• Country of Origin: United States

Fitment

Designed for Mercruiser Stern Drive engines using the equivalent freeze plug listed below.

Replaces (OEM)

• Mercruiser 19-34270

Frequently Asked Questions

What is the part number for this freeze plug pack? The Manufacturer Part Number is Sierra 18-5961-9, covering the full pack of 8 freeze plugs.

What size are the freeze plugs in the Sierra 18-5961-9 pack? Each freeze plug in this pack measures 1-5/8 inch.

How many freeze plugs are included? The 18-5961-9 pack contains 8 freeze plugs of the same 1-5/8 inch size.

What material is the Sierra 18-5961-9 freeze plug made from? It is made from bronze, which resists corrosion better than steel or brass in a marine engine environment.

Does this freeze plug interchange with an OEM Mercruiser part? Yes, the Sierra 18-5961-9 is designed to be interchangeable with Mercruiser Stern Drive part 19-34270.

How much does the 18-5961-9 pack weigh? The pack of 8 freeze plugs weighs 0.61 pounds.

What color is this freeze plug? The Sierra 18-5961-9 freeze plug has a gold finish.

Where is the Sierra 18-5961-9 freeze plug manufactured? This freeze plug is manufactured in the United States.

Is a larger size available if 1-5/8 inch is not the right fit? Sierra also offers an 18-5962-9 freeze plug pack in a 1-3/4 inch size for applications needing the larger bore.

Is the Sierra 18-5961-9 a genuine part or an aftermarket equivalent? It is a Sierra International part built to meet or exceed original equipment quality standards.

Can I buy a single freeze plug instead of the full pack? The 18-5961-9 is sold only as a pack of 8 freeze plugs, not individually.

What is a freeze plug used for on a marine engine? A freeze plug like the Sierra 18-5961-9 seals a core casting hole in the engine block or manifold and is a common replacement item during internal engine service.