2017-2021 Acura NSX Radiator: A Guide to the Complex Front-Mounted Cooling System

Understanding the NSX's Multi-Radiator System

The second-generation Acura NSX (NC1) features a complex cooling architecture with three separate radiators mounted at the front of the vehicle to cool the gasoline engine. The largest is the center Primary Radiator (OEM Part No. 19010-58G-A01), with smaller Auxiliary Radiators on the left and right sides. It is crucial to correctly identify which radiator has failed before ordering a replacement. This guide focuses primarily on the main center radiator, but the symptoms and inspection advice apply to all three.

Symptoms of a Failing Radiator

While the 2017-2021 NSX is not known for widespread radiator issues, any vehicle's radiator can fail. Recognizing the signs early is key to preventing catastrophic engine damage from overheating.

• Engine Overheating: The most obvious sign is the engine temperature gauge climbing into the red zone. On a high-performance car like the NSX, overheating can cause severe engine damage very quickly.
• Visible Coolant Leaks: Finding puddles of brightly colored fluid (typically blue for Honda/Acura Type 2 coolant) under the front of your car is a clear sign of a leak. The leak could come from the radiator core, the seams where the plastic end tanks meet the aluminum core, or the hose connections.
• Sweet Smell: The ethylene glycol in antifreeze has a distinct sweet smell. If you notice this smell around your car, especially when the engine is warm, it's a strong indicator of a coolant leak, even if you can't see it.
• Low Coolant Level: The NSX owner's manual recommends checking the coolant reservoir frequently. If you constantly need to add coolant, there is a leak somewhere in the system that needs to be found and fixed.
• Steam from Under the Hood: If you see steam coming from the front of the car, pull over immediately and shut off the engine. This indicates coolant is escaping and boiling on hot surfaces, meaning the system is no longer pressurized and cannot cool the engine effectively.

Known Issues, TSBs, and Recalls

As of mid-2024, there are no specific recalls or widespread Technical Service Bulletins (TSBs) related to the radiators or engine cooling system for the 2017-2021 Acura NSX. Searches for common problems on owner forums do not reveal a pattern of premature radiator failure.

However, owners should be aware of other recalls for this vehicle, which include:

• Fuel Tank Crossover Pipe: A recall was issued for 2017-2018 models due to improperly welded crossover pipes between the left and right fuel tanks, which could lead to a fuel leak.
• Center High-Mount Brake Light: Some 2017 models were recalled for a potential short circuit in the third brake light that could cause all brake lights to fail.
• Fuel Pump Motor: A recall was issued for certain 2017-2020 models for a faulty fuel pump motor.

You can check if your specific vehicle is affected by any recalls by entering your VIN on the Acura recalls website or the NHTSA website.

Buying a Used 2017-2021 NSX Radiator

Given the high cost of a new OEM radiator, a quality used OEM unit from a reputable recycler is an excellent value. Aftermarket options exist, but for a precision-engineered vehicle like the NSX, a used OEM part often provides better fitment and guaranteed compatibility with factory mounting points and fan shrouds.

Inspection Checklist for a Used Radiator:

• Check the Part Number: First, ensure you are buying the correct radiator. The main center unit is 19010-58G-A01. Verify if you need the center, left, or right radiator.
• Inspect for Physical Damage: Look for significant bending of the cooling fins. While a few bent fins are cosmetic, large areas of crushed fins will impede airflow and reduce cooling efficiency.
• Examine End Tanks and Seams: Carefully inspect the plastic end tanks for any cracks, especially around the hose inlets/outlets. Check the seams where the plastic tanks are crimped to the aluminum core for any signs of weeping or chalky coolant residue, which indicates a slow leak.
• Look for Corrosion: Check the hose connections for any heavy corrosion or damage. This can prevent a proper seal with the coolant hoses.
• Internal Inspection: Look inside the inlet and outlet ports. If you see heavy, sludgy buildup or a rusty color, it may indicate the previous vehicle was run with old or improper coolant, and the radiator could be partially clogged.

Replacement Overview & Procedure

The replacement process involves removing the front bumper cover and other body panels to access the radiators. Because the engine is in the middle of the car, the cooling system contains very long coolant pipes running underneath the chassis. This makes bleeding the air out of the system extremely difficult without specialized equipment.

Professional technicians use a vacuum-lift tool (such as an Airlift) to pull a deep vacuum on the entire cooling system and then use that vacuum to draw fresh coolant in, ensuring no air gets trapped. Failure to perform this step correctly will almost certainly result in air pockets, leading to overheating and potential head gasket failure.

Related Parts to Replace

When replacing the radiator, it is highly recommended to also replace the following components:

• Radiator Hoses: The rubber hoses that connect to the radiator can become brittle and weak over time. Replacing them is inexpensive preventative maintenance.
• Radiator Cap: The cap is responsible for holding pressure in the system. A weak cap will lower the boiling point of the coolant and can cause overheating.
• Thermostat: While not attached to the radiator, the cooling system will be drained, making it the perfect time to replace the thermostat as a preventative measure.

Cost Comparison

Prices for the main center radiator can vary. Labor costs for an NSX will be significantly higher than for a standard vehicle due to the complexity of removing the front bodywork and the special bleeding procedure required.

Frequently Asked Questions (FAQ)