Duramax Engine Cover Coolant Plug 1.1" Bore (WCF100025)

Billet aluminum plug for the 1.1" coolant port in the Duramax engine cover. It replaces the factory plastic plug that gets brittle and weeps with age, seals on a high-temperature silicone O-ring, and comes black anodized so it matches the rest of a cleaned-up engine bay.

Machined from 6061-T6 billet, so it will not crack or deform under underhood heat cycling the way the plastic original does. Press it into the 1.1" bore and the O-ring does the rest. Confirm your engine cover uses the 1.1" (28 mm) port before ordering.

Part Number: WCF100025

• CNC machined 6061-T6 billet aluminum
• Black anodized finish
• Fits the 1.1" (28 mm) coolant bore in the Duramax engine cover
• High-temperature silicone O-ring seal included
• Direct replacement for the brittle factory plastic plug
• Made in USA

• Verify the port size on your engine cover is 1.1" (28 mm) before ordering.

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