Genuine BMW M30 Thermostat Housing 11531250352 – 1974

Genuine used BMW thermostat housing for early M30 inline-six engines, manufactured in 1974.

The aluminium housing carries casting number 1 250 351.9 and a circular date marking that appears to read 7/4, indicating approximately July 1974.

This is an original early-style BMW thermostat housing with the characteristic rounded thermostat cover. It is suitable for restoration, refurbishment or use as an original replacement on a compatible early M30 engine.

Because BMW used different sensor configurations, hose connections and thermostat-cover designs throughout M30 production, always compare the original housing carefully before ordering.

Details

• Part: Thermostat housing assembly
• Manufacturer: BMW
• Manufacturer type: Genuine OEM/OE
• Engine family: Early BMW M30 inline-six
• Material: Cast aluminium
• Condition: Used – untested
• Casting date: Approximately July 1974
• Visible date marking: 7/4
• Casting number: 1 250 351.9
• Corresponding BMW number: 11531250352
• Included: Thermostat housing and rounded thermostat cover
• Supplied exactly as shown in the photographs

BMW Thermostat Housing Part Numbers

The number 1 250 351.9 cast into the housing is a casting or manufacturing number, not the complete BMW ordering number.

The corresponding early BMW part number is:

• 11531250352 — 11 53 1 250 352

Known BMW supersession sequence:

• 11531250352 — 11 53 1 250 352
• 11531263058 — 11 53 1 263 058
• 11531271475 — 11 53 1 271 475
• 11531272703 — 11 53 1 272 703
• 11531272870 — 11 53 1 272 870
• 11531278187 — 11 53 1 278 187
• 11531710959 — 11 53 1 710 959 — final later replacement version

Later replacement housings may have different sensor ports, hose connections, thermostat covers and sealing arrangements. The supersession numbers therefore do not mean that every version is externally identical to this early 1974 housing.

Associated Thermostat Components

Parts associated with this early-style thermostat housing include:

• 11531250356 — 11 53 1 250 356 — early thermostat cover
• 11531714861 — 11 53 1 714 861 — later replacement cover
• 11531250357 — 11 53 1 250 357 — thermostat-cover paper gasket
• 11531254065 — 11 53 1 254 065 — 80°C thermostat associated with the early housing
• 11531250399 — 11 53 1 250 399 — thermostat sealing ring
• 11531266459 — 11 53 1 266 459 — associated water or bypass hose

These reference numbers are provided to help identify the housing. The parts are not included unless physically present and visible in the photographs.

Vehicle Compatibility

Depending on the vehicle’s production date, engine version and cooling-system configuration, this early thermostat housing may be suitable for select BMW models with an M30 engine, including:

• BMW E3: 2500, 2800, 3.0 S, 3.0 Si, 3.3 L and 3.3 Li
• BMW E9: 2500 CS, 2800 CS, 3.0 CS, 3.0 CSi and 3.0 CSL
• BMW E12: 525, 528, 528i and 530i

The same basic thermostat housing was later superseded for additional M30 applications. However, this early 1974 configuration should not automatically be considered interchangeable with every later E23, E24, E28, E32 or E34 installation.

Always verify compatibility using the vehicle’s VIN, production date, existing housing, number of required sensor ports and hose arrangement.

Condition

Used original BMW component in unrestored condition.

The aluminium housing shows visible age-related wear, oxidation, dirt, old coolant deposits and surface discolouration. Oxidation is also visible around several coolant-hose connections.

The housing, internal thermostat and thermostat cover have not been function-tested or pressure-tested. The presence and condition of the thermostat underneath the cover have not been verified.

Cleaning and careful inspection are required before installation. Replacement of the thermostat, paper gasket, sealing rings and other service parts is recommended.

Important Notes

• Casting number: 1 250 351.9
• BMW ordering number: 11531250352
• Visible casting date: 7/4 – approximately July 1974
• Compare all mounting points and coolant connections before ordering
• Confirm the required sensor-port configuration for your vehicle
• Internal thermostat has not been inspected or tested
• Housing has not been pressure-tested
• Install using new gaskets and sealing rings
• Only the components shown in the photographs are included
• Ideal for restoration or refurbishment of an early BMW M30 cooling system