Have you ever wondered which Chinese factories produce the most reliable rear main seals to keep your engine running smoothly? If you’re dealing with oil leaks and need a trustworthy replacement, this article is for you. We’ll compare the top rear main seal manufacturers in China to help you make the best choice for your vehicle.
How Bad is a Rear Main Seal Leak?
Product Details: The rear main seal is a critical component located at the back of the engine, sealing the crankshaft as it exits the engine and connects with the transmission. It is typically made of silicone or rubber and is subject to high oil pressure and the constant wear from the spinning crankshaft. To replace the seal, either the engine or transmission must be removed, along with the oil pan, making it a costly and labor-intensive process.
Pros:
– The rear main seal does not cause catastrophic engine failures immediately; it u…
– Preventative maintenance such as frequent oil and filter changes can prolong the…
Cons:
– A rear main seal leak can cause significant problems, including rapid oil deplet…
– Replacing the rear main seal is one of the most expensive jobs due to the seal’s…
– The leak can be dangerous as it can lower engine oil levels quickly, leading to…
– Diagnosing a rear main seal leak can be tricky as oil leaks can come from variou…
What is a Rear Main Seal? (And How to Spot it Failing)
Product Details: A rear main seal is a rubber gasket that seals the rear of the crankshaft, preventing engine oil from leaking out into the transmission. It is typically made of materials such as molded synthetic rubber, nitrile rubber, polyacrylate, silicone, Viton®, or PTFE. The seal is crucial for maintaining oil levels within the engine and preventing leaks that could lead to more serious engine problems.
Pros:
– Prevents oil leaks from the crankshaft into the transmission
– Available in various materials offering different benefits such as heat resistan…
– Some designs include ribs or helixes to direct oil back into the engine, improvi…
– Can be restored or sealed using oil additives like BlueDevil Rear Main Sealer
Cons:
– Failure can lead to costly repairs, often requiring the removal of the transmiss…
– Wear and tear over time can cause the seal to deteriorate, leading to oil leaks
– Repair can be labor-intensive and expensive, typically costing £500 to £800 or m…
– If not addressed promptly, oil leaks can result in low oil levels, causing furth…
Rear main seal leak????
Product Details: Rear main seals are components used in engines to prevent oil leaks between the crankshaft and the engine block. They are typically made of rubber or other sealing materials and are crucial for maintaining engine integrity and preventing oil loss.
Pros:
– Prevents oil leaks and maintains engine performance
– Available from various manufacturers such as Felpro and NAPA
– Can be replaced with the crankshaft still in the engine following specific proce…
Cons:
– Often prone to leaking, especially after warming up the engine
– Installation can be tricky, and incorrect installation can lead to immediate lea…
– May require multiple replacements to find a seal that does not leak
the rear main leak – MJ Tech: Modification and Repairs
Product Details: The rear main seal is a critical component that prevents engine oil from leaking out where the crankshaft meets the transmission. Repairing or replacing it often involves significant labor, such as disconnecting the battery, jacking up the vehicle, draining the oil, and either removing the transmission or pulling the engine. Products like Blue Devil Rear Main Sealer or Lucas Engine Oil Stop Leak are sometimes used as temporary fixes.
Pros:
– Temporary sealers like Blue Devil or Lucas can delay the need for a full repair,…
– Regular oil changes and using higher viscosity oil may help manage the leak temp…
Cons:
– Full repair requires extensive labor and can be costly, involving either transmi…
– Temporary sealers are not a permanent solution and may not completely stop the l…
Replaced Rear Main Seal on 396 Still Leaking, other Causes
Product Details: The discussion revolves around the replacement of the rear main seal on a 396 engine. Key points include that the leak was present from the beginning after the replacement, and it manifests as oil dripping down the inside of the bell housing and the inspection cover. The crankshaft showed a worn ring where the seal sat, and a new one-piece rubber oil pan gasket was used. The leak is not significant but noticeable, with oil spots on the floor and some oil on the transmission and transmission cross member.
Pros:
– Using a new one-piece rubber oil pan gasket can help in identifying if the leak…
– Inspecting the crankshaft for wear rings can help determine if the crankshaft is…
Cons:
– The replacement of the rear main seal did not resolve the leak, indicating poten…
– The presence of a worn ring on the crankshaft where the seal sat suggests that t…
Rear Main Seal Leak
Rear Main Seal Leaking! | The H.A.M.B.
Product Details: The discussion revolves around a rear main seal used in a 1955 Chevrolet V8 engine. The user installed a neoprene rear main seal during the engine rebuild.
Cons:
– The neoprene rear main seal started leaking immediately after the first start of…
– Despite proper installation, the seal failed to prevent oil leakage.
rear main seal leaking? 2007 nnbs 5.3 – GMC Truck Forum
Product Details: The discussion on the website does not provide specific product details about the rear main seal itself, but it mentions a problem with a leaking rear main seal on a 2007 GMC Sierra with a 5.3L engine. The user reports an engine oil low message and finds the bell housing soaked with oil, indicating a leak from the rear main seal. The truck has 100,800 miles and the user questions whether this issue would have been covered under the factory warranty.
Cons:
– The rear main seal can leak, causing significant oil loss and potential engine d…
– The issue can arise even when the vehicle is still within a relatively moderate…
– It may not be covered under warranty if the mileage exceeds the warranty limit.
Gen Rear Main Oil Seal
Product Details: The rear main oil seal discussed is not a specific product but rather a component of a generator. It is mentioned that the rear main oil seal does not fail catastrophically and can take time to develop a significant leak. Factors contributing to the leak include high temperatures (over 130F), diesel dilution of the engine oil, and excessive crankcase pressure. The solution involved adjusting crankcase pressure and addressing other engine issues such as a failed valve seat and improper crankcase ventilation.
Pros:
– Rear main oil seals do not fail catastrophically or quickly, allowing time for r…
– Adjusting crankcase pressure to slightly negative can help reduce or eliminate t…
– Addressing other engine issues like failed valve seats and improper ventilation…
Cons:
– High temperatures can cause the rear main seal to harden and leak massively.
– Diesel dilution of the engine oil can worsen the leak.
– Replacing the rear main seal is a big job and requires specific parts and possib…
– Excessive crankcase pressure can exacerbate the leak.
Rear Main Seal Issues | Reb’s AMC and Jeep Hideout
Product Details: The discussion revolves around rear main seals for vehicles, specifically focusing on brands like Fel-Pro and MAHLE. The user has experienced issues with both brands, including leakage and seal failure. Initially, the Fel-Pro brand seals, now made in Germany, had chunks coming out of them. The user then switched to MAHLE seals but continued to encounter leakage issues even after multiple replacements.
Cons:
– Fel-Pro seals made in Germany had chunks coming out, leading to leakage.
– MAHLE seals also leaked despite multiple replacements.
– Seal failure occurred even after thorough cleaning and proper installation.
– Possible reaction between the seal and brake clean used for cleaning the cranksh…
Comparison Table
| Company | Product Details | Pros | Cons | Website |
|---|---|---|---|---|
| How Bad is a Rear Main Seal Leak? | The rear main seal is a critical component located at the back of the engine, sealing the crankshaft as it exits the engine and connects with the tran… | – The rear main seal does not cause catastrophic engine failures immediately; it u… – Preventative maintenance such as frequent oil and filter chang… | – A rear main seal leak can cause significant problems, including rapid oil deplet… – Replacing the rear main seal is one of the most expensive jobs… | www.china-oilseals.com |
| What is a Rear Main Seal? (And How to Spot it Failing) | A rear main seal is a rubber gasket that seals the rear of the crankshaft, preventing engine oil from leaking out into the transmission. It is typical… | – Prevents oil leaks from the crankshaft into the transmission – Available in various materials offering different benefits such as heat resistan… -… | – Failure can lead to costly repairs, often requiring the removal of the transmiss… – Wear and tear over time can cause the seal to deteriorate, lea… | www.china-oilseals.com |
| Rear main seal leak???? | Rear main seals are components used in engines to prevent oil leaks between the crankshaft and the engine block. They are typically made of rubber or… | – Prevents oil leaks and maintains engine performance – Available from various manufacturers such as Felpro and NAPA – Can be replaced with the cranks… | – Often prone to leaking, especially after warming up the engine – Installation can be tricky, and incorrect installation can lead to immediate lea…… | www.vintage-mustang.com |
| the rear main leak – MJ Tech: Modification and Repairs | The rear main seal is a critical component that prevents engine oil from leaking out where the crankshaft meets the transmission. Repairing or replaci… | – Temporary sealers like Blue Devil or Lucas can delay the need for a full repair,… – Regular oil changes and using higher viscosity oil may help ma… | – Full repair requires extensive labor and can be costly, involving either transmi… – Temporary sealers are not a permanent solution and may not com… | comancheclub.com |
| Replaced Rear Main Seal on 396 Still Leaking, other Causes | The discussion revolves around the replacement of the rear main seal on a 396 engine. Key points include that the leak was present from the beginning… | – Using a new one-piece rubber oil pan gasket can help in identifying if the leak… – Inspecting the crankshaft for wear rings can help determine if… | – The replacement of the rear main seal did not resolve the leak, indicating poten… – The presence of a worn ring on the crankshaft where the seal s… | www.chevelles.com |
| Rear Main Seal Leak | www.cherokeeforum.com | |||
| Rear Main Seal Leaking! | The H.A.M.B. | The discussion revolves around a rear main seal used in a 1955 Chevrolet V8 engine. The user installed a neoprene rear main seal during the engine reb… | – The neoprene rear main seal started leaking immediately after the first start of… – Despite proper installation, the seal failed to prevent oil le… | |
| rear main seal leaking? 2007 nnbs 5.3 – GMC Truck Forum | The discussion on the website does not provide specific product details about the rear main seal itself, but it mentions a problem with a leaking rear… | – The rear main seal can leak, causing significant oil loss and potential engine d… – The issue can arise even when the vehicle is still within a re… | www.gmfullsize.com | |
| Gen Rear Main Oil Seal | The rear main oil seal discussed is not a specific product but rather a component of a generator. It is mentioned that the rear main oil seal does not… | – Rear main oil seals do not fail catastrophically or quickly, allowing time for r… – Adjusting crankcase pressure to slightly negative can help red… | – High temperatures can cause the rear main seal to harden and leak massively. – Diesel dilution of the engine oil can worsen the leak. – Replacing th… | mvdirona.com |
| Rear Main Seal Issues | Reb’s AMC and Jeep Hideout | The discussion revolves around rear main seals for vehicles, specifically focusing on brands like Fel-Pro and MAHLE. The user has experienced issues w… | – Fel-Pro seals made in Germany had chunks coming out, leading to leakage. – MAHLE seals also leaked despite multiple replacements. – Seal failure occ… |
Frequently Asked Questions (FAQs)
Frequently Asked Questions About Rear Main Seal Leaks
What is a rear main seal and where is it located?
The rear main seal is a rubber gasket that seals the rear of the crankshaft, which is the part of the engine that connects to the transmission. It prevents engine oil from leaking out of the crankcase and into the transmission housing.
What are the common causes of a rear main seal leak?
A rear main seal leak can be caused by several factors, including normal wear and tear, worn main bearings, a bad PCV valve, low oil levels, crankshaft problems, and transmission alignment issues. These causes can lead to friction between the seal and the crankshaft, resulting in oil leaks.
How can I identify a rear main seal leak?
To identify a rear main seal leak, look for oil dripping from the rear side of the engine, near where it connects to the transmission. You might see oil stains on the transmission bell housing or the area around it. Cleaning the engine and running it to check for drips can help confirm the leak.
What are the potential consequences of a rear main seal leak?
A rear main seal leak can lead to significant issues if not addressed. It can cause a fast oil leak, quickly draining your engine oil, which can result in severe internal engine damage and expensive repairs. While it doesn’t usually cause catastrophic engine failure immediately, it can lead to more serious problems over time.
How difficult and expensive is it to replace a rear main seal?
Replacing a rear main seal can be quite expensive and labor-intensive. It often requires removing either the engine or the transmission, and sometimes the oil pan as well. This complexity makes it one of the more costly repairs, similar to replacing head gaskets or rebuilding the transmission. However, it’s a necessary fix to prevent further engine damage.