Oil Plug

Red plug closing the oil filler opening on the pump drive mechanism. Fitted directly on the filler neck, above the oil level sight glass.

Application

The plug closes the oil filler neck (Öleinfüll-Stutzen) after filling or topping up the oil level in the pump drive mechanism. It prevents oil leakage and keeps contaminants out of the oil chamber during operation.

Symptoms – when to replace

• The plug doesn't seal tightly and oil seeping around the filler thread is visible.
• The plug's thread is worn or damaged and it cannot be tightened fully.
• The plug body is cracked or discolored, especially after operation in high ambient motor temperature.
• The plug is seized in the filler neck and removing it requires excessive force, risking damage to the thread in the neck.

How to choose the right part

Selection is based on reference number 43437 – the same plug fits both the 18mm plunger variant (Kränzle 115-155) and the 14mm variant (Kränzle 185), as it seats on an identical filler neck regardless of the drive variant.

Note the suffix on the number – the "43.437 2" variant (Öleinfüllschraube) used on K 1050 TS/P is a different catalog item, despite the similar base number.