Sierra 18-5849 Shrouded Trim Relay, White, for Mercury 100 HP 4 Cylinder Outboards

The Sierra 18-5849 is a shrouded trim relay used to control the power trim and tilt circuit on applicable outboard engines. The white shrouded housing encloses the internal contacts to help shield them from moisture, salt spray, and debris in the engine compartment, while the panel mount design allows it to install into the same relay location as the original part. It is built as a three-terminal, quick-connect relay with a normally open contact configuration and nickel iron alloy contacts for consistent switching performance under repeated trim and tilt cycling.

This relay is engineered to meet or exceed the specifications of the original equipment part it replaces, and it is interchangeable with a number of OEM and aftermarket cross-reference numbers, making it a straightforward replacement for boat owners who need to restore trim function without waiting on an OEM-only part. It fits Mercury 100 HP 4 cylinder outboards equipped with 1 Ram Trim and a 5/16-18 starter terminal.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5849
• Product Type: Shrouded Trim Relay
• Connector Type: Quick Connect
• Contact Material: Nickel Iron Alloy
• Contact Type: Normally Open
• Mounting Type: Panel Mount
• Number of Terminals: 3
• Operation Mode: Motor
• Color: White
• Weight: 0.6 pounds

Fitment

• Mercury 100 HP 4 Cylinder outboards with 1 Ram Trim and 5/16-18 starter terminal

Replaces (OEM)

• CDI 852-9819
• Chrysler/Force/US Marine 828151
• Chrysler/Force/US Marine 828151A1
• Mallory 9-15210
• Mercruiser Stern Drive 882751A1
• Mercury Marine 828151
• Mercury Marine 828151A1
• Mercury Marine 882751A1
• Mercury Marine 882751A2

Frequently Asked Questions

What does the Sierra 18-5849 relay do? The Sierra 18-5849 is a shrouded trim relay that controls the power trim and tilt circuit on applicable outboard engines, switching power to the trim motor when the operator raises or lowers the drive.

Will the 18-5849 fit my Mercury outboard? The 18-5849 fits Mercury 100 HP 4 cylinder outboards equipped with 1 Ram Trim and a 5/16-18 starter terminal; check your engine's trim configuration and starter terminal size against these details before ordering.

Is the 18-5849 relay interchangeable with OEM Mercury Marine relays? Yes, the 18-5849 cross-references to Mercury Marine 828151, 828151A1, 882751A1, and 882751A2, along with Mercruiser Stern Drive 882751A1, so it can directly replace those OEM numbers.

Does the 18-5849 cross-reference to any non-Mercury brands? Yes, this relay also cross-references to CDI 852-9819, Chrysler/Force/US Marine 828151 and 828151A1, and Mallory 9-15210.

How many terminals does the 18-5849 relay have? It has 3 terminals and uses a quick-connect connector type, with a normally open contact configuration.

What material are the contacts made of? The internal contacts on the 18-5849 are made of nickel iron alloy, chosen for reliable switching under repeated trim and tilt use.

What color is the 18-5849 relay housing? The housing is white with a shrouded design that helps protect the internal contacts from moisture and debris.

How is the 18-5849 relay mounted? It uses a panel mount design, allowing it to install into the same mounting location as the original relay it replaces.

How much does the 18-5849 relay weigh? The Sierra 18-5849 trim relay weighs 0.6 pounds.

Is the Sierra 18-5849 an OEM part or an aftermarket replacement? The 18-5849 is a Sierra-manufactured replacement relay engineered to meet or exceed the specifications of the original equipment part it replaces, rather than an OEM Mercury Marine part itself.

What is included when I order the 18-5849? You receive one Sierra 18-5849 shrouded trim relay, ready to install in place of the original trim relay.