Hydraulic valve tappet. Porsche 993 Carrera / 993 Carrera RS  ❭  99310514107

Hydraulic Tappet 
Sold each - 12 required per car

Restore smooth and quiet valve train operation with this OE Match Hydraulic Tappet, designed for the Porsche 993. Manufactured to original equipment specifications, this replacement hydraulic tappet helps maintain correct valve clearance automatically, reducing valve train noise and supporting consistent engine performance.

Fits:

• Porsche 993 (911) C2 1994-97
• Porsche 993 (911) C4 1994-97
• Porsche 993 (911) RS 1994-97
• Porsche 993 (911) C2S 1994-97
• Porsche 993 (911) C4S 1994-97 
  

Diagram Ref No 25

Hydraulic tappets are an important part of the Porsche 993 valve train, helping the engine run smoothly without the need for regular manual valve clearance adjustment.

What Does the Hydraulic Tappet Do?

The hydraulic tappet, also known as a hydraulic valve lifter, sits within the valve train and uses engine oil pressure to maintain the correct clearance between moving valve components.

Its main functions include:

• Maintaining correct valve clearance automatically.
• Reducing valve train noise.
• Supporting smooth valve operation.
• Helping maintain efficient engine performance.
• Reducing wear on camshaft and valve train components.
• Compensating for thermal expansion as the engine warms up.

A correctly functioning hydraulic tappet helps ensure quiet, reliable and efficient engine operation.

Why Do Hydraulic Tappets Fail?

Hydraulic tappets operate under constant load and rely on clean engine oil to function correctly. Common causes of failure include:

• Oil contamination or sludge build-up.
• Low oil pressure.
• Internal wear after high mileage.
• Blocked oil passages.
• Poor maintenance or extended oil change intervals.
• Engine overheating.
• Wear to internal check valves or plungers.

When a tappet can no longer maintain oil pressure correctly, it may collapse or become noisy, causing tapping sounds from the valve train.

When Should the Hydraulic Tappet Be Replaced?

Replacement is recommended if you notice:

• Persistent tappet ticking or tapping noise.
• Noisy valve train after warm-up.
• Rough running caused by poor valve operation.
• Loss of performance linked to valve train wear.
• Wear found during engine inspection.
• During cylinder head overhaul or engine rebuild.

Many Porsche specialists recommend replacing worn hydraulic tappets during major engine work to restore smooth operation and protect surrounding valve train components.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99310514107

The product you are viewing cross references to these numbers