COMPONENTSPLUS B185-9110A3 Rear Crankshaft Seal 320/320B 1990S-2005

( Brand: Componentsplus ), ( Manufacturer Part Number: B185-9110A3 ), ( Part Type: Seal Crankshaft ), ( Source: Aftermarket )

Review COMPONENTSPLUS Rear Crankshaft Seal Caterpillar 320/320b 1990 S-2005 185-9110

The **ComponentsPlus B185-9110A3 Rear Crankshaft Seal** is a high-performance, precision-engineered sealing component specifically designed for Caterpillar diesel engines, including the robust **320/320B series** produced between the early 1990s and mid-2000s. This seal is a critical component of the engine s rear main bearing housing, ensuring a reliable oil-tight barrier between the crankshaft and the surrounding casing to prevent leaks, contamination, and premature wear. Crafted from durable **nitrile rubber (NBR) with a reinforced steel backing**, the seal is engineered to withstand the extreme pressures, temperatures, and mechanical stresses inherent in heavy-duty industrial applications. Its **lip-style design** provides an optimal seal against oil leakage while accommodating minor shaft movement, reducing friction and extending both the seal s lifespan and the engine s overall reliability. The **A3 variant** of this seal incorporates enhanced engineering to improve durability and resistance to oil degradation, making it ideal for long-haul, high-load environments where engine longevity is paramount. Whether installed in construction equipment, marine applications, or stationary power generators, this seal delivers consistent performance, minimizing downtime and maintenance costs. ComponentsPlus ensures compatibility with OEM specifications, guaranteeing a perfect fit for the **Caterpillar 320/320B** engines from the late 1990s through the early 2000s, making it a trusted replacement for original equipment manufacturers parts.

**Pros and Cons of buying a ComponentsPlus B185-91110A3 Rear Crankshaft Seal (Caterpillar 320B/320C, 1990s 2005)**

1. **OEM Compatibility** This seal is designed as an original equipment replacement for the Caterpillar 320B/320C models, ensuring a precise fit and reliable performance. It matches the specifications of the factory seal, reducing the risk of leaks or premature wear.

2. **High-Quality Materials** ComponentsPlus is a reputable supplier known for using durable materials, including high-grade elastomers and reinforced housing. This seal is built to withstand the harsh conditions of heavy-duty diesel engines, including heat, pressure, and vibration.

3. **Extended Lifespan** A properly installed OEM-quality seal reduces the likelihood of frequent replacements, saving time and labor costs in the long run. It is designed to last the expected service life of the engine under normal operating conditions.

4. **Ease of Installation** The seal is pre-lubricated in some cases and designed for straightforward installation, which can help reduce downtime compared to aftermarket parts that may require additional sealing or adjustments.

5. **Warranty and Support** ComponentsPlus offers warranties on their parts, providing some assurance against defects. Additionally, their technical support can assist with installation or compatibility questions.

6. **Prevents Costly Damage** A failing rear crankshaft seal can lead to oil leaks, which may contaminate hydraulic systems or cause bearing damage. Replacing it proactively avoids secondary damage and extends the engine s overall lifespan.

7. **Availability and Reliability** As an OEM or OEM-equivalent part, it is widely available through authorized distributors, reducing the risk of ordering counterfeit or low-quality alternatives.

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1. **Higher Upfront Cost** Compared to generic or aftermarket seals, this OEM-quality part may be more expensive. However, the long-term reliability often justifies the cost.

2. **Potential Overkill for Light Use** If the machine is used infrequently or in mild conditions, the seal may outlast its intended service life, making it a more expensive replacement than necessary.

3. **Installation Complexity** While designed for ease, replacing a rear crankshaft seal still requires careful handling to avoid damaging the seal or engine components. Improper installation can void warranties or lead to leaks.

4. **Limited Customization** Unlike some aftermarket options, this seal does not offer variations in material or design. If the machine operates in extreme conditions (e.g., high temperatures or corrosive environments), additional precautions may be needed.

5. **Depreciation Risk** If the machine is older and nearing the end of its useful life, investing in an OEM seal may not provide a significant return on investment. The cost could be better spent on upgrading other critical components.

6. **Compatibility Verification Needed** While this seal is specified for the 320B/320C, confirming the exact model year and engine variant is crucial. Mixing up part numbers could lead to incorrect fits or performance issues.

7. **Labor Costs** Replacing a rear crankshaft seal often requires specialized tools and expertise, adding to the total cost if professional labor is needed.

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The **ComponentsPlus B185-91110A3 rear crankshaft seal** is a strong choice for maintaining or restoring the reliability of a Caterpillar 320B/320C engine from the 1990s to mid-2000s. Its OEM-quality construction ensures durability, reduces the risk of leaks, and prevents secondary damage to the engine. While the upfront cost is higher than some aftermarket alternatives, the long-term benefits including extended seal life, reduced downtime, and peace of mind make it a worthwhile investment for machines that are still in active service.

For machines with high hourly usage or those operating in demanding conditions, this seal is particularly justified. However, if the equipment is nearing retirement or used sporadically, the cost may not align with the expected return. Always verify the exact model and engine specifications before purchasing to ensure compatibility.

- The machine is a Caterpillar 320B/320C from the specified years.

- The engine is in regular use or operates under heavy loads.

- You prioritize long-term reliability and want to avoid leaks or related damage.

- You have access to proper installation tools or professional labor.

- The machine is rarely used or nearing the end of its service life.

- You are working with a tight budget and can find a reputable aftermarket seal with strong reviews.

- The seal is being replaced as part of a larger overhaul, and other components (e.g., bearings, oil seals) are also being upgraded.

For most operators, the **ComponentsPlus seal is the best choice** for its balance of quality, compatibility, and performance. Pair it with proper installation techniques and regular maintenance to maximize its lifespan.

Details:

Warranty does not cover failure due to accident, abuse, neglect or as the result of normal wear and tear. ComponentsPlus products, when properly installed, are warranted against defects in materials and workmanship to the original purchaser for a period of one 1 year from date purchase. Product Notice. Rear Crankshaft Seal Fits Caterpillar 320/320B 1990 s-2005 185-9110: CATERPILLAR EXCAVATORS: 311/311B/312/312B 3064T/3066T Diesel 1990 s-2005, 314/315/318/318C 320/320B/320C INDUSTRIAL: C4.2/C6/C6.4 1990 s-2005.

FITS / Replacement Part Numbers: OEM PART NUMBERS: Caterpillar: 185-9110 Primary rear crankshaft seal, 1859110 Alternative format, SPECIFICATIONS: Material: Nitrite Rubber, APPLICATION: Compatible with Caterpillar 311 1990 s-2005.

part #: b1859110a3 prices

• $55.13-$108.42

specifications cranshafengin:

• for makes: Caterpillar
• brand: Componentsplus
• mpn: B185-9110a3
• part type: Seal Crankshaft
• source: Aftermarket

general cranshafengin:

• Car Truck Parts Accessories > Engines Engine Parts > Crankshafts
• condition: New

shipping cranshafengin:

• service: Economy, Standard, Expedited, Overnight
• type: Fixed
• cost: $0.00
• transit: 3-7 Days
• class: Economy, Standard, Expedited, One-day

offer cranshafengin:

• options: Ship-to-home
• started: March 9, 2026
• sold: 0
• availability: In Stock

payments cranshafengin:

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

returns cranshafengin:

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

seller cranshafengin:

• rating: 98.9%
• # reviews: 52643
• city: Morrisville, North Carolina

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