Crankcase Parts

Oil tube seal for crankcase distribution oil pipes.
Sold each.



Fits:
Porsche 911 1970-89
Porsche 964 1989-94
Porsche 993 1994-98

Click 'Zoom in' for large parts diagram.
Diagram Ref No 14.

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Related, superseded, cross reference or alternative numbers for comparison.

9997071124A

The product you are viewing cross references to these numbers

Oil tube seal for crankcase distribution oil pipes.
Round oil return tube O-ring used at the outer ends of the crankcase oil distribution / return tubes. Each tube uses two seals, and a complete engine typically requires multiple O-rings depending on tube type and configuration (often eight per engine on many 911/964/993 applications).
Sold each.

Fits:
Porsche 911 1970 - 1989
Porsche 964 1989 - 1994
Porsche 993 1994 - 1998

Diagram ref no 14.

This seal provides a leak-tight joint between the oil return tube and the crankcase or associated oil galleries. By sealing the tube ends, it:
• Prevents engine oil leaks at the tube junctions.
• Helps maintain correct oil circulation and system pressure.
• Keeps oil off the heat exchangers, exhaust and underside of the engine, reducing smells, smoke and contamination.

With age, heat and constant oil exposure, original O-rings can harden, flatten, crack or shrink. When they fail:
• Oil begins to weep or drip from the crankcase / tube junctions.
• The underside of the engine, heat exchangers and exhaust can become oil-soaked, causing burning smells and smoke.
• You may see oil spots under the car and gradual oil loss between services.

Replacing tired seals is a low-cost, high-impact fix that significantly reduces leaks and keeps the engine bay cleaner.

When to Replace
Consider replacing these oil tube seals if:
• You see oil leaks or dampness around the oil return tubes or crankcase unions.
• The engine is undergoing an oil return tube replacement (solid or collapsible).
• You’re performing an engine refresh, top-end rebuild, or major oil system service.
• The car shows persistent oil drips on the floor despite other seals being renewed.

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Related, superseded, cross reference or alternative numbers for comparison.

9997071124A

The product you are viewing cross references to these numbers

Oil tube. (Non Collapsible)
The OE Match Oil Tube (Non-Collapsible) is a high-quality replacement engine lubrication component designed to transport engine oil between critical parts of the lubrication system. Manufactured to OE specifications for fit, durability and performance, this rigid oil tube ensures a reliable flow of oil throughout the engine, helping to maintain proper lubrication, cooling and oil pressure.  
Sold Each.
x4 Required Per Car.

Fits:

• Porsche 911 1965-1968 2.0L / 912 SWB (F)
• Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 911 1978-1983 3.0L / SC
• Porsche 911 1984-1986 3.2L
• Porsche 911 1987-1989 3.2L G50
• Porsche 911 1975-1977 3.0L Turbo (930)
• Porsche 911 1978-1989 3.3L Turbo (930)
• Porsche 964 (911) C2 1989-93
• Porsche 964 (911) C4 1989-93
• Porsche 964 (911) RS 3.6L 1991-93
• Porsche 964 (911) RS 3.8L 1991-93
• Porsche 964 (911) TURBO 3.3L 1991-93
• Porsche 964 (911) TURBO 3.6L 1991-93
• 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
• Porsche 993 (911) TURBO 1994-96
• Porsche 993 (911) GT2 1994-97
• Porsche 993 (911) TURBO S 1994-97  

Diagram Ref No 13

Constructed to replicate the original factory design, this non-collapsible oil tube provides a secure and dependable oil passage capable of withstanding the high temperatures, pressures and vibration associated with normal engine operation. It is an essential component for maintaining the health and longevity of the engine's lubrication system.  

What This Product Does:

• Transfers engine oil between lubrication system components.
• Maintains consistent oil flow and oil pressure.
• Supports lubrication of critical engine parts.
• Assists with engine cooling through oil circulation.
• Helps ensure efficient operation of the lubrication system.
• Provides a secure, leak-resistant oil passage.
• Supports long-term engine reliability and performance.

Symptoms Of Wear Or Failure:

• Visible engine oil leaks.
• Oil drips beneath the vehicle.
• Low engine oil level between services.
• Oil residue around oil line connections.
• Reduced engine oil pressure.
• Oil pressure warning light illumination.
• Burning oil smell from oil contacting hot engine components.
• Corrosion, cracking or physical damage to the oil tube.
• Signs of oil seepage at connection points.

Why Replacement Matters:

• Engine oil tubes operate in demanding conditions and are continually exposed to heat, pressure fluctuations, vibration and environmental contaminants. Over time, corrosion, fatigue, physical damage or deteriorated sealing surfaces can lead to leaks and reduced lubrication system efficiency.
• A damaged oil tube can result in oil loss, reduced oil pressure and insufficient lubrication of critical engine components. If left unresolved, oil leaks can contribute to accelerated engine wear, overheating and potentially severe engine damage. Even minor leaks can worsen over time and create reliability and maintenance concerns.
• Replacing a worn or damaged oil tube restores proper oil circulation and helps maintain the integrity of the engine lubrication system. An OE Match replacement provides factory-style fitment, dependable performance and long-term durability, ensuring reliable oil delivery and continued protection for your Porsche engine.

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

90110735101

The product you are viewing cross references to these numbers

Oil Tube (non Collapsible). Stainless steel.
O-rings required part number  9997071124A
Price is for 1 but there are 4 per engine.

Fits:
Porsche 911 2.0L 1965 - 1969
Porsche 911 1970 - 1989
Porsche 964 1989 - 1994
Porsche 993 1994 - 1998

Diagram Ref No 13.

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

90110735101

The product you are viewing cross references to these numbers

Oil Tube. (Non Collapsible)
Sold Each.
x4 Required Per Car.

Fits:
Porsche 911 911 2.0L 1965>>1969
Porsche 911 1970>>1989
Porsche 964 1989>>1994
Porsche 993 1994>>1998

Diagram Ref No 13

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

90110735101

The product you are viewing cross references to these numbers

Rear Main Oil Seal. 90 x 110 x 12.
Fitting Position: Transmission End, Inner Diameter: 90 mm, Outer diameter: 110 mm, Width: 12 mm, Radial Shaft Seal Design



Fits:
Porsche 964 1989-94
Porsche 993 1994-98
Porsche 996 Turbo / GT2 / GT3 MKI

Porsche 944 - All models including 944S, 944 Turbo & 944S2 built 1982-1991

Porsche 924S - All models built 1986-1988

Porsche 928 - All models built 1986-1995

Porsche 968 - All models built 1992-1995

Click 'Zoom in' for large parts diagram.
Diagram Ref No. 21

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

99911342641

The product you are viewing cross references to these numbers

Rear Main Oil Seal for Porsche 

Restore engine sealing integrity and prevent costly oil leaks with this OE Match Rear Main Oil Seal for the Porsche 964, Porsche 993 and Porsche 996. Manufactured to OE specifications and measuring 90mm inner diameter, 110mm outer diameter and 12mm width, this critical engine seal is designed to prevent engine oil escaping around the rear of the crankshaft where it exits the engine case and connects to the flywheel assembly.

Fits:

• Porsche 964 (911) C2 1989-93
• Porsche 964 (911) C4 1989-93
• Porsche 964 (911) RS 3.6L 1991-93
• Porsche 964 (911) RS 3.8L 1991-93
• Porsche 964 (911) TURBO 3.3L 1991-93
• Porsche 964 (911) TURBO 3.6L 1991-93
• 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
• Porsche 993 (911) TURBO 1994-96
• Porsche 993 (911) GT2 1994-97
• Porsche 993 (911) TURBO S 1994-97
• Porsche 996 TURBO 2000-05
• Porsche 996 GT2 2001-05
• Porsche 996 GT3 MKI 1999-02
• Porsche 924S 2.5L 1986-87
• Porsche 924S 2.5L 1988
• Porsche 944 2.5L 8V 1982-87
• Porsche 944 2.7L 8V 1988-89
• Porsche 944S 2.5L 16V 1987-88
• Porsche 944S2 3.0L 16V 1989-91
• Porsche 944 Turbo 2.5L 8V 1985-88
• Porsche 944 Turbo 2.5L 8V 1989-91
• Porsche 944 Turbo S 2.5L 8V 1988
• Porsche 968 3.0L 1992-94
• Porsche 968 Sport 3.0L 1994-95
• Porsche 968 CS 3.0L 1993-95
• Porsche 968 Turbo S 3.0L 1993-94
• Porsche 928 4.5L 1978-82
• Porsche 928S 4.7L 1981-83
• Porsche 928S2 4.7L 1984-86
• Porsche 928S4 5.0L 1987-92
• Porsche 928GT 5.0L 1989-91
• Porsche 928GTS 5.4L 1992-95

Diagram Ref No. 21

The rear main oil seal, often referred to as the RMS (Rear Main Seal), is one of the most important sealing components in the engine. It retains engine oil inside the crankcase while allowing the crankshaft to rotate at high speed. A worn or damaged seal can lead to oil leaks, clutch contamination and unnecessary engine maintenance costs if left unattended.

This OE Match replacement provides the correct fit, sealing performance and durability required for maintenance, engine rebuilds and preventative servicing.

What Does the Rear Main Oil Seal Do?

The rear main oil seal forms a seal around the rear section of the crankshaft.

Its primary functions include:

• Preventing engine oil leaks
• Sealing the rear crankshaft opening
• Protecting the flywheel area from contamination
• Maintaining correct engine oil levels
• Preventing oil reaching the clutch assembly
• Supporting long-term engine reliability
• Allowing smooth crankshaft rotation

Without a properly functioning rear main seal, oil can escape from the engine and create a range of reliability issues.

Why Do Rear Main Oil Seals Fail?

Like all rubber sealing components, rear main oil seals are subject to wear and ageing.

Common causes of failure include:

• Heat cycling
• Age-related hardening
• Crankshaft wear
• Engine vibration
• Long-term oil exposure
• Improper installation
• Excessive crankcase pressure
• High mileage use

Over time, the sealing lip can lose flexibility and its ability to maintain consistent contact with the crankshaft surface.

Symptoms of a Failing Rear Main Oil Seal

Common warning signs include:

• Oil leaks between engine and gearbox
• Oil drips beneath the vehicle
• Oil contamination around the flywheel housing
• Clutch slip caused by oil contamination
• Burning oil smell
• Gradual oil level loss
• Oil residue on transmission bellhousing

Because the seal is located behind the flywheel, leaks can often be mistaken for other engine oil leaks unless properly diagnosed.

When Should the Rear Main Oil Seal Be Replaced?

Replacement is recommended when:

• Oil leakage is present
• The gearbox is being removed
• Replacing the clutch assembly
• Rebuilding the engine
• Refurbishing the crankshaft
• Carrying out preventative maintenance
• The original seal shows signs of ageing
• Engine mileage is high

Many Porsche specialists recommend replacing the rear main seal whenever the clutch or flywheel is removed, as labour access is significantly easier during these procedures.

Why Replacement Matters

A leaking rear main oil seal can lead to far more expensive repairs if ignored.

Benefits of replacement include:

• Prevention of engine oil leaks
• Protection of the clutch assembly
• Improved engine cleanliness
• Reduced maintenance costs
• Improved reliability
• Professional rebuild standards
• Long-term sealing performance
• Greater peace of mind

Replacing the seal during clutch or engine work is considered a smart preventative maintenance measure.

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

99911342641

The product you are viewing cross references to these numbers