Just overhauled the engine and want that “wow” factor when you lift the bonnet.

Is water leaking from around the thermostat housing or hose?

Thermostat cover has corroding away?

Time to replace it before you do further damage to your engine and run the risk of cooking your engine.

We have a top quality genuine Mercedes replacement part to suit the job.


This part will suit the following MB applications: -

  • M121.921
  • M121.928
  • 190SL


This kit is shown as no 43 in the diagram above


Original Part Nos:-



A121 203 01 74

121 203 01 74

121 203 0174



Don’t not pay over $300 for a genuine part. Our price only $85.00


Please check you have the correct part number for your vehicle.

Most parts available for M121 engines and 190SL vehicles.


McStarparts – “Keeping classic Benz’s on the road.”

Mercedes M121 & 190SL Thermostat top cover Pt No: - 121 203 01 74, 1212030174

SKU: 121-203-01-74RZ
  • Lead time for this part is:- 10 - 12 working days

  • International buyers – please note: Import duties, taxes, and charges aren’t included in the item price or postage cost. These charges are the buyer's responsibility. Please check with your country's customs office to determine what these additional costs will be prior to bidding or buying.

"Keeping Classic Benz's On The Road"

Kevin McCarthy
+61 0418 634 080

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