Yamaha - Water Pressure Hardware Kit 3.3L Cooling System Component 6P2-83728-00-00. Overview. If you're running a 3.3L Yamaha, keeping an eye on water pressure isn't optional-it tells you exactly how your cooling system is doing. I've rigged setups where adding a proper pressure kit made it a lot easier to catch issues before they turned into overheating problems. When everything's installed right, you get real-time feedback and a lot more confidence pushing the motor. It's one of those upgrades that just makes sense once you've used it.. Key Features. • Real-Time Water Pressure Monitoring - Provides accurate feedback on cooling system performance.• Complete Hardware Kit - Includes necessary components for proper installation and setup.• OEM-Compatible Design - Built to integrate cleanly with Yamaha 3.3L systems.• Supports Engine Protection - Helps identify cooling issues before they become serious problems.. Engine & Boat Compatibility. Designed for Yamaha 3.3L outboard engines and si