ALLAN AIRCRAFT PRODUCTS 4C187 Nos Valve Safety Relief 4820-00-757-3231

( Brand: Allan Aircraft Products ), ( Manufacturer Part Number: 4C187 ), ( Part Type: Valve Safety ), ( Country Of Origin: United States )

Review ALLAN AIRCRAFT PRODUCTS Nos Valve Safety Relief

The Allan McDonald Aerospace 4C187 NOS (New Old Stock) Valve is a crucial safety component designed specifically for aircraft applications. Its part number is 4820-00-757-3231. This valve is a safety relief valve, which means it is responsible for preventing overpressure in a system by releasing excess pressure when necessary.

The 4C187 Valve is made from high-quality materials that are resistant to extreme temperatures and corrosion, ensuring reliable performance in the demanding conditions of aviation. The valve body is constructed from forged 6061-T6 aluminum, while the valve components, including the stem, seat, and disk, are made from stainless steel.

This particular valve is a direct replacement for the original equipment installed on various aircraft models. It features a compressor discharge flow capability of 11.1 lbs/min (49.9 kg/min) and an inlet pressure range of 0-2,500 psi (0-172.4 bar). The valve also has an outlet pressure relief setting that can be adjusted from 1,200 psi (8.3 bar) to 2,500 psi (172.4 bar) to meet specific aircraft system requirements.

The 4C187 Valve comes with a new O-ring seal, ensuring a tight and leak-free installation. It is designed to meet the rigorous standards of military and commercial aviation, including MIL-P-25781 and FAR-25.

Installing this valve is a straightforward process, and it can be done with standard hand tools. The valve is also compatible with various actuator types, including pneumatic and electric actuators, which makes it a versatile solution for different aircraft systems.

In summary, the Allan McDonald Aerospace 4C187 NOS Valve is a high-performance, reliable, and versatile safety relief valve specifically designed for aircraft applications. Its high-quality construction, adjustable pressure setting, and compatibility with various actuator types make it an essential component for maintaining the safety and integrity of aircraft systems.

The Allan McCollum Aviation 4C187 No. Valve Safety Relief (NSRV) 4820-00-757-3231 is a vital component used in aircraft fuel systems to prevent overpressure situations. Here are some pros and cons that can help you make an informed decision about purchasing this part:

1. Safety: The primary function of the NSRV is to ensure safety by releasing excess fuel pressure when necessary. This can prevent damage to the fuel system and potentially catastrophic failures.

2. Compliance: Adhering to regulatory requirements is essential in aviation. This part is a military-specified item, meaning it meets the highest standards for quality and performance.

3. Reliability: The NSRV is designed to operate in extreme conditions, including high altitudes and temperatures. It is built to withstand the rigors of aviation use and provide consistent performance.

4. Interchangeability: The 4C187 NSRV is widely used in various aircraft models, making it a versatile option for many applications.

1. Cost: The military-specification and critical nature of this component contribute to its higher cost compared to commercial alternatives.

2. Complexity: The NSRV has several components and requires precise installation to function correctly. Proper installation should be performed by a certified technician to ensure safety and performance.

3. Maintenance: Regular maintenance is crucial for the NSRV to function optimally. This includes periodically checking for leaks, corrosion, and other potential issues.

In conclusion, the Allan McColllum Aviation 4C187 No. Valve Safety Relief 4820-00-757-3231 is a valuable investment in aviation safety. Its primary function in preventing overpressure situations and ensuring regulatory compliance make it a worthwhile investment. However, its higher cost and complexity necessitate careful consideration and professional installation. Ultimately, the decision to purchase this part should be based on the specific requirements and safety considerations of your aircraft operation.

If you operate an aircraft and require a reliable and safe fuel system component, the Allan McColllum Aviation 4C187 No. Valve Safety Relief 4820-00-757-3231 is a recommended option. Its proven performance and adherence to military standards make it a smart investment for any aviation application. However, ensure that you work with a certified technician for proper installation and maintenance to maximize its benefits and ensure safe operation.

Details:

FEAT Special Features Hex 0.688 in.; thru hole 0.590 in. Check tech info below. DOA both sides, Stylist -in cartridge. LOC F1-A3N-B6-S3-C5 NOS USGI surplus.

part #: 4c187 price

• $38.40

specifications aviationpar:

• brand: Allan Aircraft Products
• mpn: 4c187
• part type: Valve Safety
• country of origin: United States

seller aviationpar:

• city: Ogden, Utah
• rating: 98.5%
• # reviews: 13474

general aviationpar:

• condition: New
• Parts Accessories > Aviation Parts Accessories > Parts

returns aviationpar:

• policy: Returns Accepted
• time: 30 Days
• paid by: Seller

shipping aviationpar:

• service: USPS Priority Mail, FedEx Ground Economy, USPS Ground Advantage
• type: Calculated
• class: Expedited, Economy, Standard
• carrier: USPS, FedEx
• transit: 5-11 Days
• cost: $12.10

payments aviationpar:

• wallet: Google-pay
• other
• credit card: Mastercard

offer aviationpar:

• sold: 0
• quantity: 4
• options: Ship-to-home
• best offers: True
• started: March 12, 2026
• availability: In Stock

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