Calorstat TH5111.88J Engine Coolant Thermostat

Engine Coolant Thermostat for BMW Cooling Systems

Calorstat TH5111.88J is a standard engine coolant thermostat built for precise temperature control in BMW cooling systems. It opens at 190.0 degrees and includes a rubber O-ring seal for a secure, leak-resistant installation.

• Standard engine coolant thermostat for belt and cooling service
• Start to open temperature: 190.0
• Gasket or seal included: Yes
• Seal type: O-Ring
• Seal material: Rubber
• Sealing flange outside diameter: 2.63
• Valve-seat diameter: 67.0
• By-pass valve diameter: 35.0
• Height between flanges: 1

Fitment and Application Details

Compatible with BMW cooling system applications including Fits 1998-2000 BMW Z3, N/A; Fits 1995-1999 BMW M3, N/A; Fits 1996 BMW 328i, N/A; Fits 1996 BMW 328is, N/A; Fits 1995 BMW 320i, N/A; Fits 1992-1995 BMW 325i, N/A; Fits 1992-1995 BMW 325is, N/A; Fits 1995 BMW 525i, N/A; Fits 1991-1992 BMW 525i, N/A; Fits 1991-1994 BMW 318i, N/A; and Fits 1991-1994 BMW 318is, N/A. Vernet is an OE supplier to BMW, and this thermostat follows the same application coverage used across these models.

What This Thermostat Helps Address

• Engine running too cool or too hot due to thermostat wear
• Delayed coolant flow control during warm-up
• Temperature fluctuation from a sticking thermostat valve
• Coolant seepage at the thermostat seal interface
• Cooling system service on BMW Z3, M3, 328i, 328is, 320i, 325i, 325is, 525i, 318i, and 318is

Installation Notes and Tips

Verify housing condition and clean the sealing surface before installation. Replace the thermostat only with the correct orientation for the cooling circuit, and confirm the O-ring seats evenly to prevent leaks. Because this part is specified by temperature and dimensions, match the original thermostat specification before assembly.

Quality Assurance

Calorstat TH5111.88J is built to OE-style specifications for BMW applications, with interchange coverage that includes Gates 34027, Motorad 274-192, NGK 48648, Quality-Built 11444, and Remy 14622 for the same application.