SKU: MMFN-L | UPC: 748354803853
Mishimoto 42mm Aluminum CNC Fill Neck MMFN-L
CNC machined from solid aluminum, the Mishimoto 42mm Aluminum CNC Fill Neck delivers precise coolant filling for custom radiator builds. Designed for welding onto fabricated aluminum radiators, it ensures reliable sealing and overflow management in performance applications. Pair it with Mishimoto radiator caps for consistent pressure handling in racing or street projects.
Key Features
- CNC Machined Aluminum: High-strength construction resists corrosion and withstands high-pressure cooling systems in demanding environments.
- 42mm Neck Diameter: Large opening allows fast coolant fills and easy viewing of fluid levels during maintenance.
- Screw-in Overflow Nipple: Integrated 1/4-inch NPT fitting connects directly to overflow tanks for clean hose routing.
- Weld-Ready Design: Flat mounting flange measures 60mm wide by 40mm high for secure TIG welding to custom radiator tanks.
- Cap Compatibility: Matches Mishimoto radiator caps for OEM-level sealing and pressure retention up to 30 PSI.
Product Notes
- Intended for welding to 0.08-inch thick aluminum radiator tanks using TIG method.
- Clean surfaces thoroughly before welding to prevent contamination.
- Compact packaging fits easily in tight shipping spaces.
Installation Notes
- Professional installation recommended.
- TIG weld to radiator tank. use argon shielding gas for clean joints.
- Hardware not included. torque cap to 4-5 Nm after install.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | All | Custom Radiator Builds | Fabrication Projects |
Why Choose Mishimoto?
- Trusted by racers worldwide for cooling components in motorsports.
- Direct-fit engineering from dyno-tested designs.
- Precision manufacturing with rigorous quality checks.
Frequently Asked Questions
-
Q: Does this fit specific vehicles?
A: Universal design fits any custom aluminum radiator fabrication project across all makes, models, and years. -
Q: What material and finish does it have?
A: Solid billet aluminum with raw machined finish ready for welding. bare aluminum requires no additional plating. -
Q: What is the warranty and install support?
A: Backed by Mishimoto lifetime technical support. stainless steel lifetime warranty, aluminum parts covered for durability.
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: 3.5 x 3.5 x 3.1 inches box
- Weight: 0.44 lbs gross shipping weight
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Shop premium Mishimoto performance parts at Black Ops Auto Works, your trusted source for Mishimoto radiators, intercoolers, oil coolers, catch cans, silicone radiator hoses, thermostats, intake systems, charge pipes, exhaust tips, wheel accessories, and cooling system upgrades. Mishimoto is known for producing high-performance cooling and airflow components engineered for reliability, fitment, and real-world performance across cars, trucks, SUVs, and off-road builds. Whether you are upgrading a street car, track build, tow rig, diesel truck, Jeep, or performance daily driver, Mishimoto products help improve cooling efficiency, airflow, oil control, durability, and engine bay performance. Shop Mishimoto Cooling, Intake & Performance Parts At Black Ops Auto Works, we carry a wide selection of Mishimoto aftermarket parts for popular performance, truck, SUV, and off-road applications. Popular Mishimoto Product Categories: Radiators & Cooling Components – Performance aluminum ...
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