MV4508 Universal Cooling System Adapter


The MV4508 Universal Cooling System Adapter is simple and quick to install in virtually any radiator or coolant reservoir neck. The rubber, step-and-cone design features a self-locking, nested cam and internal restrictor combine. This provides a secure, airtight seal with only a single rotation of the expansion knob. The unique adapter is fully self-contained - no component change is required - so there are no extra parts to maintain. Also, its compact size allows for convenient storage in a toolbox. 

The MV4508 is an economical alternative to application-specific adapters. It fits pressure pumps with a common radiator neck-style connection. The MV4805 replaces more than 20 individual adapters used to pressure test the cooling systems on cars, vans and light- and heavy-duty trucks.


The Mityvac Universal Cooling System Adapter utilizes a multi-step, expandable rubber bushing design to adapt to the radiator and expansion tank filler necks on most domestic and import automobiles. Each of the five steps on the bushing has a unique diameter ranging from ¾" (20 mm) up to 1½" (40 mm). The diameters are designed slightly smaller than the most common filler neck sizes. So that the adapter easily installs into the filler neck until the largest possible diameter fits with only slight interference. The tension knob is then rotated causing the bushing to expand and securing the adapter in the neck. 

Once properly installed, the adapter forms an airtight seal with the radiator or expansion tank. It can be utilized for vacuum, pressure or temperature related diagnostics as well as evacuating and refilling coolants while eliminating air locks.

The Mityvac Universal Cooling System Adapter will not fit every automotive radiator and expansion tank available. However, it can be used in conjunction with many specialized adapters. If the sole intended use of the universal adapter is for a specific or unique application, please verify the size and depth of the application for proper fitting.


  • Replaces more than 20 individual cooling system pressure test adapters for cars, vans, light- and heavy-duty trucks
  • Patent-pending cam mechanism helps to ensure an air-tight seal with radiator and coolant bottle necks
  • Compact one-piece design fits conveniently in tool box
  • Compatible with Stant-style cooling system pressure pumps


  • Universal Radiator Test Adapter (1 piece)


Packaged weight0.60 lbs. (0.27 kg)
Packaged size2.6 x 2.4 x 6.7 in. (65 x 60 x 170 mm)

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