Description
Product Overview
The SEI Marine Cam Follower Kit is a direct replacement for OE part 850315A, designed for inline 3‑ and 4‑cylinder outboard lower units ranging from 50‑125 HP two‑stroke to 50‑150 HP four‑stroke models. Crafted from hardened steel, the kit features a manual lift mechanism that provides precise camshaft positioning and smooth operation under demanding marine conditions. With a compact package measuring 12 x 10 x 2 inches and weighing just 2 pounds, it offers easy handling and storage. The kit includes all necessary components for a complete installation, ensuring a perfect fit for Mercury, Mariner, and Force outboards produced from 1987 to the present day.
Usage
Designed for marine environments, this cam follower kit excels in both recreational and commercial boating applications. Whether you are performing routine maintenance on a weekend fishing trip or conducting a full engine overhaul in a professional service shop, the kit’s robust construction resists corrosion and wear caused by saltwater exposure. It is ideal for boat owners, marine mechanics, and outboard service technicians who demand reliable camshaft control to maintain optimal engine performance and fuel efficiency.

Why Choose Us
SEI Marine Products has a reputation for delivering high‑quality marine components that meet stringent OEM standards. This cam follower kit undergoes rigorous testing to ensure dimensional accuracy and durability, providing confidence that the replacement will perform at or above original specifications. The manual lift design simplifies installation, reducing labor time and minimizing the risk of damage during assembly. Backed by a strong customer rating of 4.7 out of 5 stars from 20 reviews, the kit demonstrates consistent satisfaction among marine professionals.
Key Features
- Direct OE replacement for part 850315A, ensuring perfect fit.
- Hardened steel construction for superior wear resistance.
- Manual lift mechanism provides precise camshaft control.
- Compatible with 3‑ and 4‑cylinder Mercury, Mariner, and Force outboards (1987‑current).
- Lightweight (2 lb) and compact packaging for easy handling.
FAQ
Does this kit fit both two‑stroke and four‑stroke outboards?
Yes, the kit is engineered for inline 3‑ and 4‑cylinder outboard lower units covering 50‑125 HP two‑stroke and 50‑150 HP four‑stroke models.
What tools are required for installation?
Standard hand tools such as a socket set, screwdrivers, and a torque wrench are sufficient. The manual lift design eliminates the need for specialized equipment.
Is this kit corrosion‑resistant for saltwater use?
The hardened steel components are treated to resist corrosion, making the kit suitable for both fresh and saltwater environments.
Can I install the kit myself, or do I need a professional?
Experienced DIY enthusiasts can install the kit using the included instructions, but professional installation is recommended for optimal results, especially in high‑performance applications.
What is the warranty on this cam follower kit?
SEI Marine offers a limited warranty that covers manufacturing defects for a period of one year from the date of purchase.






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