Genuine BMW M30 NOS Thermostat Housing 11531278187

Genuine BMW New Old Stock thermostat housing for M30 inline-six engines, manufactured around 1981/1982.

This housing was installed once on a restored vehicle, but the restoration project was canceled before the vehicle was completed. The part was therefore never put into service and has not been used in an operating cooling system.

Because it was previously installed, a small amount of gasket residue remains on one connection/mating surface. Minor installation and storage marks may also be present. Please inspect all product photos carefully.

Details

• Part: Thermostat housing
• Manufacturer: BMW
• Manufacturer type: Genuine OEM/OE
• Engine family: BMW M30 inline-six
• Material: Cast aluminum
• Condition: New Old Stock – previously installed once, never used
• Approximate casting period: 1981/1982
• Casting number: 1 250 351.1
• Configuration: Multiple threaded ports for temperature sensors, switches, and plugs
• Included: Bare thermostat housing only
• Supplied exactly as shown in the product photos

BMW Part Numbers

Based on the casting period, the corresponding period BMW part number is:

• 11531278187 — 11 53 1 278 187

Associated earlier and superseding BMW part numbers:

• 11531250352 — 11 53 1 250 352
• 11531271475 — 11 53 1 271 475
• 11531272870 — 11 53 1 272 870
• 11531278187 — 11 53 1 278 187
• 11531710959 — 11 53 1 710 959 — final superseding part number

The number 1 250 351.4 cast into the housing is a casting number and not a separately orderable BMW part number.

BMW Part Number Supersession

The thermostat housing was updated several times during production:

• 11531250352 — early version
• 11531271475 — intermediate version
• 11531272870 — used approximately from September 1980 through January 1982
• 11531278187 — used approximately from September 1981 through March 1986
• 11531710959 — later and final superseding version

The production periods overlap because BMW introduced updated versions gradually and listed some versions as retrospectively interchangeable.

Vehicle Compatibility

Depending on the model, production date, engine version, and required sensor configuration, this thermostat housing may be suitable for the following classic BMW models equipped with an M30 engine:

• BMW E3: 2500, 2800, 3.0 S, 3.0 Si and 3.3 L/Li
• BMW E9: 2500 CS, 2800 CS, 3.0 CS, 3.0 CSi and 3.0 CSL
• BMW E12: 525, 528, 528i and 530i
• BMW E23: 728, 728i, 730, 732i, 733i and 735i
• BMW E24: 628 CSi, 630 CS, 633 CSi and 635 CSi
• BMW E28: 525i, 528i, 533i, 535i and M535i

The later superseding housing number 11531710959 is also cataloged for selected M30-powered BMW E32 730i/735i and BMW E34 530i/535i models. Compatibility with these later vehicles depends on the required sensor and plug configuration.

Condition

Genuine BMW New Old Stock component. The housing was previously mounted during a restoration project, but the vehicle was never completed and the part was never put into service.

A small amount of gasket residue is visible on one connection/mating surface. The housing may also show minor marks from installation, removal, and long-term storage. These details are visible in the product photos and do not represent normal operating wear.

Important Notes

• This listing is for the bare thermostat housing only
• Temperature sensors, switches, plugs, thermostat, thermostat cover, O-ring, gasket, and mounting hardware are not included
• The threaded ports are empty, as shown in the photos
• The correct sensors and plugs depend on the vehicle’s model, production date, market version, and wiring harness
• Clean the mating surfaces and remove any remaining gasket material before installation
• Always install the housing with the correct new gasket and seals
• Compare the casting, hose connections, mounting points, and threaded ports with your original part before ordering
• If you are unsure about compatibility, please contact us with your VIN and the part number from your original thermostat housing
• Rare genuine BMW component, ideal for an OEM-correct restoration