Gates 33118 Engine Coolant Thermostat

Gates 33118 Heavy-Duty Thermostat Overview

The Gates 33118 heavy-duty engine coolant thermostat is built for demanding cooling systems in trucks, buses, tractors, and heavy equipment. Its top by-pass design and 180°F opening temperature help regulate coolant flow in applications that face constant vibration and harsh underhood conditions.

Gates Heavy-Duty Thermostat 33118 is part of the Green Stripe line, a product family focused on heavy-duty cooling components for commercial and off-highway service. For buyers searching for a Gates thermostat 33118 replacement or a heavy-duty thermostat for truck and equipment cooling repair, this part delivers a direct-fit service option where the application calls for this specification.

Key Features

• Engine coolant thermostat with heavy-duty construction
• Top by-pass design for specified cooling system layouts
• Starts to open at 180°F / 82°C
• Built from steel, brass, and copper
• Sealing flange outside diameter: 2.46 in.
• Height between flanges: 1.51 in.
• Valve diameter: 1.6 in.
• Single seal design with no jiggle pin weep hole

Product Details

The Gates 33118 thermostat is engineered for heavy-duty cooling service where stable temperature control matters. Its metal construction and top by-pass configuration support consistent coolant routing in systems used on commercial trucks, buses, tractors, and heavy equipment. If you are sourcing a Gates 33118 thermostat for a cooling system repair, this part matches the listed dimensions and operating temperature for the specified application.

This part cross-references Four Seasons 33118 and Stant 14558 for the same application.

Common Cooling System Issues

• Engine running too cool or too hot due to thermostat wear
• Delayed coolant circulation after startup
• Temperature fluctuation under load in heavy-duty service
• Cooling system service needs on truck, bus, tractor, or equipment applications
• Replacement of a thermostat with the same 180°F opening specification

Installation Notes and Tips

Verify the thermostat housing style, by-pass configuration, and dimensions before installation. Clean the sealing surfaces thoroughly and inspect the coolant system for contamination, gasket residue, or housing damage. Confirm the replacement thermostat matches the required opening temperature and flange measurements for the vehicle or equipment application.

Compatible With heavy-duty truck, bus, tractor, and heavy equipment cooling systems where this thermostat specification is required. For make/model-specific searches, use Gates 33118 with the exact cooling system dimensions and temperature rating.

Quality Assurance

Gates positions the Green Stripe Heavy-Duty Thermostat line for service in environments with high noise, vibration, and harshness under the hood. The 33118 is built to meet those operating demands with a metal-bodied thermostat design for heavy-duty cooling applications.