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OE Match
This OE Match L-shape check valve is a replacement one-way valve used in the windscreen washer system on selected Porsche models. It is designed to control washer fluid flow through the washer hose circuit and helps prevent fluid from draining back into the reservoir.
Sold individually, quantity required depends on model and washer system layout
Fits:
Porsche 911 1981 - 1989
Porsche 964 1989 - 1994
Porsche 968 >> 1993
Porsche 924 1977 - 1988
Porsche 928 1978 - 1986
Porsche 944 1983 - 1991
Diagram ref no 29
The check valve allows washer fluid to flow in one direction toward the washer jets while stopping reverse flow when the washer system is not in use. This helps keep fluid closer to the spray nozzles, improving washer response when the windscreen washer is activated.
Functions:
• Controls one-way washer fluid flow
• Helps prevent washer fluid from draining back through the hose
• Supports faster washer jet response
• Helps maintain washer system pressure
• Reduces delay before fluid reaches the windscreen
• Helps prevent air pockets in the washer line
• OE Match replacement for the original L-shape washer check valve.
Why Replace This Part?
A faulty check valve can allow washer fluid to drain back into the system, causing delayed spray, weak washer jet output, or no fluid delivery at first activation. The valve can also become blocked, cracked, brittle, or leak due to age, washer fluid additives, and engine bay heat. Replacing the check valve helps restore reliable washer operation and keeps the windscreen cleaning system working correctly.
When to replace:
• Washer fluid takes too long to reach the windscreen
• Washer jets spray weakly or inconsistently
• Fluid drains back after the washer system is used
• The valve is cracked, leaking, blocked, or brittle
• Washer hoses have been replaced or removed
• The washer system has air in the lines
• The windscreen washer system is being restored or repaired.
Where it fits on the car
This L-shape check valve fits in the windscreen washer hose circuit, between the washer reservoir/pump and washer jets. Depending on the model and washer hose layout, it may be positioned near the washer nozzles, under the front bonnet, or along the washer fluid line.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
477955481
The product you are viewing cross references to these numbers
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- 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 924 2.0L 1976-79
- Porsche 924 2.0L 1980-85
- Porsche 924 Turbo 2.0L 1979-81
- Porsche 924 Turbo 2.0L 1982-84
- Porsche 924 Carrera GT 2.0L 1981
- Porsche 924 Carrera GTS 2.0L 1982
- 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
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Concentrated Windscreen cleaner that helps keep windscreens free of road debris, grease, insect remains and ice
- Suitable for winter and summer use
- Prevents freezing down to minus 10° C
- Store in clean and dry conditions away from other combustible materials, heat and direct sunlight.
- Solvent based screen cleaner
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The NAPA Summer Screenwash 5L NCSW8005L is a seasonal windscreen cleaning fluid formulated to help keep vehicle glass clean and clear during warmer weather. Supplied in a convenient 5-litre container with a green formulation, it is designed for use in the vehicle's windscreen washer system to tackle everyday summer contamination and maintain good visibility.
Summer driving can quickly leave the windscreen covered with insects, road grime, dust and traffic film. Using a dedicated screenwash rather than plain water provides improved cleaning performance, helping the washer and wiper system remove deposits more effectively.
What This Product Does:
Screenwash is stored in the vehicle's washer reservoir and delivered through the washer jets onto the windscreen when the washer system is activated.
Working together with the windscreen wipers, NAPA Summer Screenwash helps loosen and remove contamination from the glass, improving visibility without requiring the driver to stop and manually clean the windscreen.
During summer, it is particularly useful for dealing with common contaminants such as:
- Insect residue
- Road grime
- DustTraffic film
- General dirt and deposits
- Light greasy contamination
Keeping the windscreen clean also allows the wiper blades to work more effectively, providing the driver with a clearer view of the road.
Symptoms Of Wear Or Failure:
Screenwash is a consumable rather than a component that mechanically wears out. Regular checks are therefore important, particularly before long journeys or periods of frequent driving.
Common signs that the washer system needs attention include:
- Low or empty washer reservoir
- Little or no fluid reaching the windscreen
- Windscreen remaining dirty after using the washers
- Increased smearing when operating the wipers
- Difficulty removing insect residue and road grime
- Washer fluid becoming dirty or contaminated
- Plain water being used instead of an appropriate screenwash
- Washer warning light appearing on equipped vehicles
If the reservoir contains sufficient fluid but nothing reaches the windscreen, the washer pump, hoses and jets should also be inspected for faults or blockages.
Why Replacement Matters:
A clean windscreen is essential for clear visibility and safer driving. Dirt, insects and traffic film can reduce visibility, particularly when driving towards low sunlight or when glare from headlights and street lighting reflects from a contaminated windscreen.
Using a suitable screenwash helps remove these deposits more effectively than relying on water alone.
Regular use can help:
- Maintain clearer windscreen visibility
- Remove stubborn summer contamination
- Reduce dirt and traffic film
- Improve washer and wiper effectiveness
- Make insect residue easier to remove
- Keep the windscreen cleaner between manual washes
Maintaining an adequate level of screenwash also ensures the washer system is ready when visibility suddenly becomes compromised while driving.
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Monday-Friday: 8.30am - 5.30pm (GMT)
Saturday: Closed
Sunday: Closed