The 5-Piece Mercury Lower Unit Washer KIT (OEM 822836) are precision washers used to secure the lower unit (gearcase) to the midsection on Mercury outboards. Built dimensions of .445" ID x .805" OD x .108" thickness, this washer ensures proper load distribution and secure mounting between the gearcase and midsection.
At Buckshot Racing #77, this washer is manufactured from stainless steel, providing a durability and corrosion-resistance upgrade over many original Mercury washers. It also serves as a direct replacement for Mercury OEM part number 12-35935, making it a widely used service component across many engines.
Stainless Steel Advantage
Many OEM washers were produced from standard steel, which can corrode over time when exposed to water, heat, and marine environments. This corrosion can weaken the washer and affect clamping force at the gearcase mounting points.
By upgrading to stainless steel, this washer offers improved resistance to corrosion, better strength under load, and longer service life. This is especially important in saltwater, offshore, and high-performance applications, where durability is critical.
Function in Gearcase Mounting
The 822836 / 12-35935 washer is used at the mounting points where the lower unit (gearcase) attaches to the midsection. It distributes clamping force from the mounting hardware, helping ensure a secure and even connection.
Proper washer condition is important for maintaining tight mounting surfaces, alignment, and structural integrity between the gearcase and midsection. Worn or corroded washers can lead to uneven clamping, loosening over time, or damage to mounting surfaces.
Using the correct washer ensures the gearcase remains securely fastened under load and vibration.
Fitment Across Mercury V6 Outboards
This washer fits a wide range of Mercury 2-stroke V6 outboards, including 2.0L, 2.4L, and 2.5L engines. Common applications include models such as 135, 150, 175, 200, and 225 HP, along with performance platforms like Black Max, XR2, XR4, XR6, XRI, Pro Max, 260 EFI, 280 ROS, S3000, and 300 Drag.
It is commonly used across gearcases found on engines such as 200 EFI Pro Max, 225 Pro Max, 200 XS, SST-120, and other Mercury Racing applications, as well as offshore and ROS setups. Mercury’s consistent mounting design makes this washer a common replacement across multiple generations.
Importance During Service
Whenever the lower unit is removed for impeller service, gearcase maintenance, or rebuilds, it is important to inspect the mounting hardware and washers. Over time, washers can become worn, compressed, or corroded.
Replacing them with a new stainless steel 822836 / 12-35935 washer ensures proper clamping force and helps prevent loosening or damage during operation.
Built for Reliability
From XR6 and Pro Max fishing engines to high-performance Mercury Racing platforms like the 260 EFI and 280 ROS, the connection between the gearcase and midsection must remain secure under extreme conditions.
The 5-Pack Mercury Lower Unit Washer KIT 822836, also replacing 12-35935, provides the correct fit along with improved corrosion resistance and durability. At Buckshot Racing #77, we supply precision components designed to keep your Mercury outboard secure, aligned, and performing reliably on the water.