Breather hose oil tank to crankcase bottom half. Porsche 911 1980-83  ❭  93010739409

Breather Hose – Oil Tank to Crankcase Bottom Half 

Maintain the integrity of your air-cooled Porsche's lubrication and crankcase ventilation system with this OE Match Breather Hose. Manufactured for precise fitment and long-lasting durability, this replacement hose restores the correct flow of crankcase vapours and oil mist between the engine and external oil tank.

Fits:

• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 911 1978-1983 3.0L / SC

Diagram ref no 35B

The dry sump lubrication system used on the classic Porsche 911 relies on a network of breather hoses to regulate crankcase pressure and allow oil vapours to circulate correctly. Over time, the original hose is subjected to constant heat, oil exposure and engine vibration, causing the rubber to harden, crack or become porous. As the hose deteriorates, oil leaks, vacuum leaks and poor crankcase ventilation can develop, leading to untidy engine bays, unpleasant oil smells and reduced engine efficiency.

Replacing this breather hose is an important part of preventative maintenance, particularly during engine rebuilds, oil system servicing or whenever ageing hoses begin to show signs of deterioration.

Manufactured to OE Match standards, this hose provides dependable sealing, correct routing and reliable long-term performance for your classic air-cooled Porsche.

What Does the Breather Hose Do?

This hose forms an essential part of the Porsche dry sump lubrication and crankcase ventilation system.

Its primary functions include:

• Carrying crankcase vapours between the engine and oil tank.
• Helping regulate crankcase pressure.
• Returning oil vapours through the lubrication system.
• Maintaining proper engine breathing.
• Supporting efficient engine operation.
• Preventing oil leakage from deteriorated hose connections.

Correct crankcase ventilation is essential for maintaining engine performance, reducing oil contamination and minimising crankcase pressure.

Why Replace the Breather Hose?

Breather hoses are constantly exposed to hot engine oil, temperature fluctuations and vibration, making them one of the more common ageing rubber components on classic Porsche engines.

Common reasons for replacement include:

• Cracked or hardened rubber.
• Oil seepage or external leaks.
• Hose becoming soft or swollen from oil exposure.
• Split hose walls.
• Vacuum leaks.
• Engine restoration.
• Oil system refurbishment.
• Preventative maintenance.

Replacing the hose before failure helps maintain the integrity of the lubrication system while preventing messy oil leaks.

Symptoms of a Failing Breather Hose

A deteriorating breather hose may cause:

• Oil leaks around the oil tank or crankcase.
• Oil smell from the engine compartment.
• Visible cracks or perished rubber.
• Increased crankcase pressure.
• Oil residue around hose connections.
• Vacuum leaks.
• Dirty engine bay caused by oil mist.
• Reduced crankcase ventilation efficiency.

Replacing the hose restores proper crankcase ventilation and helps protect the engine from unnecessary oil loss and contamination.

Benefits

• Restores efficient crankcase breathing.
• Helps maintain correct crankcase pressure.
• Reduces the risk of oil leaks.
• Supports reliable dry sump lubrication system operation.
• Straightforward direct replacement.
• Long-lasting, durable construction.

When replacing breather hoses, it is advisable to inspect the remaining crankcase ventilation hoses, hose clips and oil tank connections, as these components often deteriorate together due to age and heat exposure.

Why Choose OE Match Engine Breather Components?

OE Match engine breather components are manufactured to provide reliable sealing, precise fitment and excellent resistance to heat and oil exposure. Designed specifically for classic Porsche applications, they help maintain the efficiency of the dry sump lubrication and crankcase ventilation system while supporting long-term engine reliability. OE Match components are trusted by enthusiasts and specialist workshops undertaking routine servicing, engine rebuilds and concours restorations.

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